Sunday, July 30, 2006

Paediatric Grand Rounds 1:8 Is Up! A 3-Ring Bonanza

Mosaic reads, Flea's 3-Ring Circus
Paediatric Grand Rounds 1:8 is up, courtesy of Ringmaster Flea of Dr. Flea's Blog. Children are not small adults but the full richness of human drama is present alongside a generous helping of bugs that are common to childhood. I am fascinated and repelled by Tara Smith's item about biofilms, screaming children and just why ear infections in children may be so resistant to antibiotics. Last time, Tara gave me nightmares about just how E. coli spreads among children: so maybe ear infections are less yukky.

Sceptic, parent, and carer for the very young, Clark Bartram is angry about the shameless manipulation of parental guilt in Move over tooth-fairy. Using unproven techniques, technologies and principles, you too can have your child's milk-teeth stored in the uncertain hope of resurrecting stem-cells from them, should the child have a future need for them.

Adding to the things that can turn parents into pale shadows of their pre-parent selves, is the vexed question about expanded genetic screening for newborns. Vexed? Surely that would be A Good Thing. Eh - not so much, according to Phillip Gordon and the man has an informed opinion on the matter.

For a range of interesting, challenging and entertaining posts, I commend this Paediatric Grand Rounds to you.

The next Paediatric Grand Rounds is scheduled for August 13 and your host is the quizzical, take-no-prisoners Clark Bartram. The hosting schedule and previous editions are available in the Paediatric Grand Rounds archive.

For more information about the images used in the illustration, click on it or visit the detail on Flickr.

Saturday, July 29, 2006

High Asthma Levels In Special Ed. Students: Correlation, Causation Or What?

Mosaic of yellow school buses1 in 3 special education students in New York City public schools has asthma; this contrasts with 1 in 5 for the general school population. These are the headline findings of an interesting survey that is soon to be published in the American Journal of Public Health: Asthma and Enrollment in Special Education Among Urban Schoolchildren.

Reuters Health interviewed Dr. Luz Claudio of the Mount Sinai School of Medicine in New York City about the study. She remarked that the numbers were "huge": explaining that in some schools, the percentage of children with asthma in special education was as high as 60%. Claudio stated that it is well known that low-income, urban children are at greater risk for poorly-controlled asthma.
It's a manageable chronic disease [but] our findings show that a lot of kids from this group are not well managed.
She speculated that,
Managing that disease successfully may remove them from special education.
Claudio and her colleague Jeanette A. Stingone wanted to investigate if a relationship existed between an asthma diagnosis and the likelihood of being in special education classes. They surveyed 24 randomly chosen New York City public elementary schools using parent questionnaires. They collected data on sociodemographic characteristics, special education enrollment, asthma diagnosis and symptoms, school absences, and use of health care services. It will be interesting to see the full questionnaire about the symptoms: I would be especially interested in any questions that asked the parents to confirm or describe sleep-disordered breathing (e.g., frequent snoring) in their children because this has been linked to learning, emotional and behavioural disorders in children.

There are several findings from the survey that lend weight to previous research.
  • 34% of students in special education classes had asthma, compared with 19% of children in the general school population (in some schools, the incidence of asthmatic children in special education classes was 60%).
  • Even after controlling for socioeconomic differences, children with asthma had a 60%greater risk of being enrolled in special education than children without the disease.
  • Children with asthma who are in special education classes are more likely to be from low-income families
  • Asthmatic children in special education classes are 3x more likely to have been hospitalised for asthma in the past year, compared to children with asthma in mainstream education.
  • Asthmatic children in special education showed other differences in asthma management:
    • they are half as likely to use a peak flow meter (used to monitor lung function and disease severity: it is used to identify a need to alter medication use)
    • they are 15% less likely to use a spacer, a commonly-recommended device that improves the delivery of asthma medication to the lungs.
Claudio could not provide a satisfactory explanation as to why asthma rates are higher among those children enrolled in special education. She acknowledged that an obvious explanation would be absenteeism due to illness. However, in this study, the children with asthma who were also enrolled in special education classes had similar school attendance rates to the asthmatic children in mainstream classes.

The authors suggest that some of the discrepancies may be attributable to differences in asthma management strategies (e.g., the peak flow meters).
Inadequate asthma control may contribute to a greater risk of asthmatic children residing in urban areas being placed in special education. School health programs should consider targeting low-income urban children with asthma at risk for enrollment in special education through increased asthma interventions and medical support services.
For my own interests, some additional data about the children's breathing and sleep habits might have been helpful. Correlation can not necessarily imply causation. However, there is an accumulation of research findings that report the high prevalence of disordered breathing in children with physical, cognitive, emotional and behavioural disorders (see above reference to sleep-disordered breathing). Asthma is a special instance of disordered breathing that may offer some interesting insight into this exploration of correlation and causation. It would be fascinating to learn if the asthmatic children in special education classes in this study were more likely to experience night-time episodes of asthma, poor-quality sleep or sleep-disordered breathing than asthmatic children in mainstream classes. Or to compare the same data for all asthmatic children with those for children without the disease.

I primarily run workshops for children in the school setting so that their teachers and other support staff can observe what I am doing, and can understand the habits that I would like them to support when I am not there. It also means that there is some opportunity to talk to parents when they are dropping-off or picking-up their children. It is not unusual for parents to notice a difference in a child and to ask about it which provides additional opportunities for education and to remind parents of the habits that I would like them to support. So, I do agree with the authors when they write:
Because children spend so much of their time in school, there is an opportunity for public health interventions during the school day aimed at improving asthma control among children who are at risk or already experience learning difficulties.
I've seen some speculation that asthma is poorly controlled in children from low-income families in the US because of prescription payment difficulties (e.g., families don't fill prescriptions for preventer medication, or they don't obtain spacers because they are not covered by medical insurance). We don't have those particular difficulties in the UK (children's prescriptions are free of charge). We probably do have families who have chaotic lifestyles who find it difficult to follow medication regimens or asthma-management plans. It would be interesting to learn if we have carried out similar surveys, and, if so, what the results are. Of course, I would also like any similar survey to ask specific questions about:
  • mucous production
  • whether the nose is frequently blocked
  • if the child mouth-breathes
  • various questions about quality of sleep and sleep-disordered breathing.
So, that would be a broadly-similar survey, that would probably be infeasibly difficult to fill out and too expensive to analyse...

Thursday, July 27, 2006

Asthma Treatment Claims May Mislead: An Editor Pulls No Punches

Graffiti to the side of a tunnel reads: Are you happy? I'm not. Change.
Charles Krauthammer recently wrote about why he loves Australia.
In the Australian House of Representatives last month, opposition member Julia Gillard interrupted a speech by the minister of health thusly: "I move that that sniveling grub over there be not further heard."

For that, the good woman was ordered removed from the House, if only for a day. She might have escaped that little time-out if she had responded to the speaker's demand for an apology with something other than "If I have offended grubs, I withdraw unconditionally."
I was reminded of this exchange when I read Dr. Ike Iheanacho's rather more decorous but equally pointed comments about trials of asthma drugs. Dr. Ike Iheanacho is the editor of the Drugs and Therapeutics Bulletin: it is an advertising-free publication that is recommended as essential reading for practising doctors. Dr. Iheanacho argues that the absence of benchmark measurements of effectiveness allows drug companies to collect and analyse several data, selecting the outcomes that best showcase their products.
Clinical trials vary greatly in the types of measures they use to assess the effects of asthma drugs, and this makes it difficult to compare different trials or to assess whether new treatments offer a genuine benefit for patients.
He highlights that beauty contests between drugs and other drugs/treatments may use assessment criteria that are more about the known properties that the drug company wants to emphasise, rather than useful comparisons of how well a drug performs in comparison to other treatments.

Dr. Iheanacho explains that a trial might collect data about asthma symptoms (e.g., cough, wheeze) and measure these. This sounds straightforward but despite the long history of pharmaceutical testing and the number of trials in this area:
symptoms can be assessed in terms of severity and frequency, but there is no universally accepted standard for scoring them, and different studies record different sets of symptoms and use different scales.
This lack of benchmarks means that it is difficult to perform cross-comparisons of data from different trials. This lack of comparable data is one of the reasons why Cochrane Systematic Reviews typically search through hundreds or thousands of trials in an area but can only include a comparatively small number that meet the rigorous standards or comparable data that can be included in their review.

Lung function is a popular parameter in trials. However, they are of dubious relevance in trials with young children because they find it difficult to co-operate with the test. Even with older children and adults, lung function measures may be inadequate and present a mis-leading picture of asthma control.

A recent assessment of children (ages 4-11) who had previously used only short-acting Beta2-agonists (common reliever medication) reported (amongst other findings) that the participants spent 55% of weeks of the study in the moderate/severe category for asthma severity. The children recorded their morning peak flow measurements: a commonly-recommended method for monitoring symptoms and used as decision-points in action plans to increase drug-use or dosages. Unfortunately, analysis of these lung function measurements showed that it is unreliable as a predictor of disease severity: it predicted only 8% of weeks in the moderate/severe category.

As you might have gathered from the above, there are differences of opinion concerning what lung function tests do and do not tell us about asthma severity. However, to return to Dr. Iheanacho's trenchant comments:
It is also important to beware of the potential for over interpretation of the secondary results of a trial: these may just add to the confusion about what is actually being measured and the drug's true effectiveness.
He summarises his criticisms as follows:
  • Exacerbations are associated with significant illness, lifestyle disruption, hospital admission, increased medical costs and risk of death. Despite this, there is no agreed definition of a mild, moderate or severe exacerbation, so there is a wide variation in the definitions used in trials.
  • Use of reliever medication (typically, inhaled short acting beta2 agonists) is frequently used as an indicator of asthma control. However, despite revisions to guidelines, some patients habitually take two puffs of bronchodilator before using an inhaled corticosteroid (this used to be a common recommendation), and many are advised to use a bronchodilator before exertion to prevent symptoms of exercise-induced asthma. This procedural use is rarely distinguished from use of a bronchodilator for acute symptom relief.
However, it is easy to criticise pharmaceutical companies: they do what they are allowed to do. The Cochrane reviewers have made similar comments about non-pharmaceutical trials. There are areas of controversy in asthma treatment and assessment (particularly for children who make up one of the largest markets) that make it difficult to agree on appropriate parameters. However, the current state of research is unacceptable if there are occasions when it is used to mislead us rather than inform us.

Wednesday, July 26, 2006

Dust Mite Avoidance, Dietary Modification: Popular Strategies Not Supported In Woolcock Study

Mosaic of images reads A is for Avoidance
We have Parkinson's Law and Murphy's Law amongst many others. Somewhere, there must be a law that catches the nuance of actions that are undertaken as a preventative but bring about the situation that they were intended to prevent: can Oedipus have both his own complex and a law? For the sake of argument, let's accept that there is an Oedipus' Law as well as the Oedipus Complex.

Anyway, there is a popular idea that by avoiding potential allergens (particularly in early life), it is possible to avoid allergic disease. There is an equally popular view that this ‘avoid everything’ strategy can compromise the development of a robust immune system and can make things worse, sensitizing the system to very low doses of allergens. The current excitement about the benefits of Omega oils and criticisms of modern diets have also lead some commentators to hypothesise that there may be a link between the incidence of asthma and the consumption of low amounts of Omega-3 (such as found in fish oils) relative to Omega-6.

A few months ago, Channel 4 broadcast an allergen avoidance experiment for controlling children's asthma. It was an interesting experiment that highlighted just how much work is involved in house dust mite (HDM) avoidance. New research from the Woolcock Institute of Medical Research in Australia explored whether HDM avoidance or dietary changes in the early years of life would help to prevent the development of asthma in children with a family history of the condition.

Dr. Guy B. Marks and his colleagues have reported that neither of these strategies was successful in preventing asthma and allergic disease in young children.

The study involved 616 children who were newborns at the time that they were recruited. The newborns all had a family history of asthma. The children were randomly allocated to HDM avoidance or control and to dietary modification or control. The HDM avoidance strategy used standard techniques such as allergen-impermeable bed-clothes and regular washing with an anti-mite detergent. For the dietary intervention, parents were encouraged to prepare children's meals with canola-based oils and to supplement their Omega-3 levels with tuna-fish oil capsules.

At the age of 5, 516 children were still available for evaluation: they were assessed for asthma and eczema and had skin prick tests for atopy. Although analysis revealed that the HDM avoidance techniques reduced bedding allergen levels by 61%, there was no significant effect on the development of asthma or the occurrence of wheeze. Disappointingly, eczema - an allergic skin condition - was more common in the HDM avoidance group than in the no-intervention group: 26% vs. 19%. It looks like a candidate for Oedipus' Law although the mechanism is not entirely clear. The dietary intervention successfully increased the ratio of Omega-3 to Omega-6, however, it did not prevent the development of asthma, wheezing or eczema.

The findings for this are very mixed, but other research indicates that, under certain circumstances, asthma can be prevented. However, the researchers for this study conclude that their findings indicate that:
the most effective, practical forms of early life environmental modification and the circumstances under which it will be appropriate to implement them remain to be established.
This is a difficult area for parents, particularly those who are anxious about their children's welfare because there is a family history of asthma or allergic conditions. However, it seems as if allergen avoidance can be difficult to implement appropriately, for sustained periods of time, and studies such as this suggest that it is of no value although others suggest that there are some benefits.

The usual research mantra of "We need more research in this area," may be true but it is of little help to parents who are considering the best prevention strategy for conditions such as eczema, asthma or hayfever in their children who may be at risk because of family history. It is essential that children who manifest multi-system atopy, (i.e. children who have all three) should have thorough clinical investigation of their allergies. Avoidance is essential in such cases but parents might also discuss immune tolerance inducing strategies such as immunotherapy with their child's medical adviser. The cautionary note here is that both allergy-testing and immunotherapy are difficult to obtain on the NHS (recent reports revealed that there are only 33 Clinical Allergists in the UK).

Australia has a high incidence of asthma and allergic conditions among children: estimates are up to 40%. Earlier this year, Professor Sly from the Perth Institute for Child Health Research announced a 2-centre project with New York in which researchers would assess the value of a vaccine that is designed to prevent asthma in children who are at high-risk for developing the disease.

Following the success of animal trials, researchers expect that the drops will successfully stimulate the immune system in such as way that the children will not develop the common allergies that trigger asthma. Over a 12-month period, 200 babies and children will receive a daily oral vaccine of common allergens. Researchers will monitor the children for the following 3 years to track whether they develop asthma.

Speaking about the vaccine, Prof. Sly said,
This is the first time anything like this has been attempted in children. These same sorts of drops are used for treatment for people who have established allergies, so we know that they're safe but what we are doing here is using these to prevent the development of allergies and no one has tried to do that before.
The researchers are to be applauded for running this trial of the drops: their success with the treatment of adults is no guarantee of their efficacy in children. Asthma rates are increasing in industrialised countries. There will be substantial medical and economic implications if this vaccine is successful: it will be interesting to see what the results are.

For more information about the images used in the illustration, click on it or visit the detail on Flickr.

Tuesday, July 25, 2006

Grand Rounds 2:44 Is Up!

the bare limbs of a hoar-frost rimmed tree are highlighted by a mixture of fog and sun against a clear blue sky: different elements co-operating to make a striking image
This week's edition of Grand Rounds is hosted and selected by Giskin, AJ and Beth from Medical Humanities. It put me in mind of the above image from Flickr - like everything else, good medicine relies on techno-stars but depends upon good communication and co-operation.

All of human life is there, and the narrative is framed around a fabulous selection of gardening images, notes and insights. The explain their metaphors:
So often matters medical are portrayed in the language of war: the fight against disease, the battle against cancer. These are the metaphors that have dominated medical discourse in the mainstream media. Yet, the military metaphor is not inevitable. Health-care professions tend their patients with the devotion and attention that gardeners lavish on their plants, hoping to keep them healthy.
There is a poem about the search for a pre-implantation genetic diagnosis for NF1. There are difficult stories, ranging from the subtle indications that someone is living with spousal abuse to the arrests following controversy about the management of some patients in the wake of Hurricane Katrina. Aetiology offers a plausible and fascinating explanation as to why repeated antibiotics may be of little efficacy in treating children's earaches.

There is a health warning as to why we should "avoid listening to Prokofiev's "Russia Under the Mongolian Yoke" under any circumstances". As Happystance commented, I can understand Stockhausen or Webern giving somebody a profound fit of the blues/yips, but Prokofiev? I vaguely remember Frank Zappa being interviewed about a piece that he described as evoking emotions similar to those one feels when listening to Webern at 4 a.m. on a foggy November morning. I don't know the Prokofiev piece in question so I am tempted to look it out but on the other hand...

I shall be dipping in and out of this all week. I commend Grand Rounds to you.

Monday, July 24, 2006

A Frivolous Suggestion That A Parasite Contributes To Chronic Illness

Icky-looking tick parasiteI've been blaming my recent insomnia on the heatwave. I'm possibly in denial about my car-crash fascination with dipping in and out of Parasite Rex: Inside the Bizarre World of Nature's Most Dangerous Creatures. In the wee smalls of the morning when I am towelling myself dry, yet again, I am given to frivolous speculations about parasites and the growth in chronic illnesses related to lifestyle choices. Or, are they choices? You have to imagine that that question was posed in a most sinister manner and accompanied by swirls of dry ice.

The parasite Sacculina must have been the inspiration for Invasion of the Body Snatchers. The Sacculina insidiously transforms crabs into pods and then blobs. The female insinuates itself into the crab via a chink in a leg joint. Unremarked, it subtly establishes itself without triggering an immune response and grows until it fills the whole body cavity of the crab, extending and wrapping root-like tendrils around the host's eyestalks.

The crab continues some vestiges of a seemingly normal life: it wanders through the surf and eats. However, over time, the Sacculina diverts the crab's energy; the crab no longer has the energy to moult or grow. If the crab loses a claw it can not re-grow it. The Sacculina eliminates those functions of the host that are superfluous to it, like reproduction. If the Sacculina inhabits a male crab it forcibly changes the crab's hormonal balance. The crab is rendered infertile. The crab's form is modified to resemble that of female with a wider and flatter abdomen, among other changes.

The Sacculina allows the host to retain enough brain, nervous system, and digestive tract to continue feeding and service its needs. The parasitised crab is neutered although it retains an instinct to nurture: it eats to serve. When the Sacculina's eggs are fertilised, the modified male or female crab broods and hatches the Sacculina's larvae as if they were its own off-spring.

If there were a Sacculina-type parasite for humans, it might be useful for it if we lost all interest in physical activities that were not directed towards affording, identifying and eating food sources. We would collapse over our computers during the day, find our way home in some form of transport that involved a minimum expenditure of energy, slump in front of the television/computer in our free time, stuffing ourselves with high calorie foods for which we can not control our appetite. Nah, that's not plausible. Although, there was something recently that implied that toxoplasma has such a powerful behavioural impact on us that it is almost indistinguishable from mind-control powers...

By and large, nothing predates on humans apart from ourselves. Parasites and bacteria have some need for us. I don't choose to think about it much, but I accept that I have a rich ecosystem of friendly bacteria living in my body that contribute to its healthy functioning (mind control courtesy of TV advertising as well as parasites) and make it more difficult for pathogenic bacteria to colonise me and cause disease.

The hygiene hypothesis and its variations suggest that people in industrialised countries do not encounter enough challenges to their immune systems to encourage its robust development or maintenance. In addition, if we co-evolved with parasites, and they contributed to our adaptation to our environment, then ridding ourselves of them over too short a time-period to allow for necessary adaptation can cause further problems. Weinstock and his colleagues experimented with treating people with active Crohn's Disease with a solution of pig whipworm in Gatorade. The treatment did bring about remission suggesting that:
it is possible to downregulate aberrant intestinal inflammation in humans with helminths.
I gave myself the horrors by recalling this on a recent sleepless night. I had the idle and frivolous thought that some hapless helminth for which I have a specie-ist revulsion might down-regulate aberrant airway inflammation in humans (e.g., asthma). I doubt it - but I have nothing on which to base that doubt apart from prejudice. That's another hot and sticky night of horrors. Except, of course, that there are bound to be some children who would be enchanted if their asthma self-management plan involved the consumption of worms or beasties guaranteed to cause revulsion in most adults within a 10 mile radius.

Sunday, July 23, 2006

Paediatric Grand Rounds Wants Your Post, Please

Mocked-up Magazine Cover For Paediatric Grand Rounds

The excellent Flea is the host of the next Paediatric Grand Rounds on July 30 at his lively blog where the issues are hot and the carnival atmosphere is strong. He invites your recommendations and submissions for the next issue on July 30 and to encourage us is displaying a lovely picture of a flea circus - go and see.

Please send the posts to Flea by Saturday 29.

You can consult both the hosting schedule and earlier editions in the Paediatric Grand Rounds archive.

Saturday, July 22, 2006

Ozone, Smogzone, Where To Get Warnings Of Levels

Blue sky with intense, glaring sunIn the UK we whinge about the weather: it's a cultural given, we don't regard it is as complaining, just part of normal conversation. We've been basking in a record-breaking heatwave. We've also had the opportunity to whinge about something we haven't had much opportunity to complain about since the Clean Air Acts: smog. Yes, the heatwave plus high levels of ground-level ozone (with some contribution from our European neighbours) means that we have ozone + pollution = smog zone warnings.

Ground-level ozone forms from the fascinating interaction of sunlight, nitrogen dioxide and other atmospheric substances that are close to the ground. Pollutants from petrol and other fuels contribute to this open-air chemical experiment.

In the UK, we can obtain updates on levels of particulate matter (PM 10 ), sulphur dioxide, nitrogen dioxide, ozone and carbon monoxide from TELETEXT (page 156), or from the Air Quality Archive, which also offers health advice people who may be particularly sensitive to air pollution. Levels are, of course, higher for people who live near busy roads.

The European Environment Agency (EEA) has just launched a new online Ozone Web tool to help us track the concentration of ground level ozone in our areas or others in which we might be interested. Nice idea, but the interface is clunky and difficult to use: I can not think who signed-off on this as an accessible, user-friendly device. Just try entering place names or post codes, or try using the pan and zoom tool to find out why I think it is too clumsy for general use.

The EEA is concerned that up to 30% of Europe's urban population is exposed to ozone levels that exceed the european safety limits. The EEA estimates that ozone pollution contributes to 20,000 deaths a year. Prof. Jacqueline McGlade is the executive director of the EEA. She promotes the release of Ozone Web:
The EU has made it obligatory for countries to alert citizens on a national level when ozone levels reach particular levels. However, Ozone Web goes much further by allowing you to monitor ozone anytime, from anywhere. You can monitor ozone levels in a neighbouring country or at a holiday destination, check recent trends and track the spread of ozone across Europe by the wind.
The standard advice is to remain indoors and to avoid exercising outdoors when ozone or smog levels are high. As ever, if you are sensitive to ozone or pollution, or if you have a respiratory condition, you might be well advised to review your action plan, check that you have your medications with you at all times, and consult your medical advisers if you have any especial concerns.

Thursday, July 20, 2006

ICS And Adrenal Suppression In Children: High Incidence, Low Significance?

Young boy using a nebuliserParents have heard horror stories about steroids and children. There was widespread publicity about the fatal accident enquiry into the death of Emma Frame who took very large doses of ICS that were out-of-licence for her age-group. The circumstances surrounding Emma's death and the severe illness of her brother, who also developed adrenal suppression, were unsettling for parents.

Even when parents know that the corticosteroids that are prescribed for their children are not the same as the anabolic steroids that are abused in some sports, they have a wariness that some doctors blame for lack of compliance with medication and treatment plans.

Adrenal suppression can happen because the body usually produces its own steroids that are essential for our immune system. When medication supplies these steroids, the body may adapt and reduce its own production. Rarely, the glands that produce these steroids may shrink and lose some of their function. If this happens, the body has reduced levels of protection during periods of stress such as illness that require greater steroid production. In addition to this, adrenal suppression in children may produce several symptoms that may show few clinical abnormalities although the child is very ill. In rare cases, there is suppression of the hypothalamic-pituitary-adrenal axis [1-3]: the headline consequences of this are that there may be a disturbance in blood sugar (a child may be irritable, confused, lethargic etc.); there may be altered consciousness and coma, convulsions and (even more rarely) death [4-6].

In a recent study, researchers looked at children who were following long-term inhaled corticosteroid (ICS) therapy for asthma. They collected data to establish whether ICS is related to adrenal and growth suppression in asthmatic children.

72 asthmatic children with a median age of 9.4 (range 4.2-15.7) had been using low to moderate doses of ICS for a median of 18 months. Data were also collected from 30 controls. Both sets of children had their peak serum cortisol levels measured: readings of less than 495 nmol/L were categorised as indicative of adrenal suppression. The children's growth and rate of growth were recorded.

20.8% of children taking ICS met the criterion for adrenal suppression: none had symptoms of adrenal suppression. Both growth measures were similar for the children with and without adrenal suppression. In addition, analysis of the data showed that the degree of adrenal suppression was independent of the level of the dose or the duration of the ICS treatment.

A striking finding is that although the children in this study were taking low-to-moderate doses of ICS almost 21% had mild adrenal suppression. The degree of retardation of growth in the children was not a significant predictor of adrenal suppression.

Following the cases of Emma and Calum Frame (as above), all of the children and adolescents who attended that children's hospital and were receiving high levels of ICS were recalled for assessment of their adrenal function.
426 children were identified, of whom 140 were receiving doses of fluticasone outside of licence. By the time of testing, only 78 children were receiving doses out of licence, but of these 34 were found to have impaired adrenal function. Of all the children tested three per cent were found to have severe impairment of cortisol production and all of these children were asymptomatic.
So, 43.5% of the children on high doses of ICS had some (unspecified) degree of impairment, with 3% showing severe impairment: it is worth noting that none of these children showed any clinical symptoms.

A 1996 study evaluated factors that might be associated with increased risk of death in a sample of 108 children or young adults who had died, and in whom death was preceded by an acute asthma exacerbation. Adrenal suppression was found in 18.7% of these cases although the people reviewed here had taken several courses of systemic corticosteroids (e.g., they had taken tablets). Although the mechanisms are not understood, the researchers
conclude that, in addition to established risk factors, complications associated with the use of systemic steroids may contribute to the risk for sudden death in this age group.
The UK Survey of adrenal crisis due to ICS [6] reported that 3 of the 28 children did not have asthma; in 5 children asthma could not account for all the respiratory symptoms, indicating a role for co-morbidities with other disorders. ICS are not effective in children with recurrent cough (a recent study suggests that persistent whooping cough may have a role) or those with episodic viral-associated wheeze (a recent conference involved an overview of these controversies).

A common trifecta for children is hayfever, eczema and asthma. It is sometimes easy to overlook that a children may also be receiving steroid treatment for the first two conditions in addition to their mild-to-moderate steroid dosage from ICS. Children may use a nose-spray that contains steroids. An FDA panel reviewed prescription-strength steroid creams in 2005. Doctors were surprised to learn that that was such a high incidence of adrenal suppression associated with using steroid creams/lotions/ointments (link requires registration): in the reported studies with children, the rate was 53-58%. These additional sources of steroids that are used on an as-needed basis may mean that there are times when a child is taking the equivalent of a high dose for some time.

Whenever children who are using ICS attend a review, and particularly if they use steroid creams for skin conditions, parents might benefit from regular reminders so that they recognise the symptoms of adrenal suppression. They may also need to discuss whether it is advisable to have a supply of oral steroids readily available to administer if their child has (e.g.) an infection and is showing symptoms and deteriorating quickly. This does increase the need for appropriate asthma education for parents. And, it needs to be closely monitored because of the risk associated with repeated courses of systemic steroids.

There is some controversy about whether physiological indications of adrenal suppression are significant in the absence of clinical symptoms. Unfortunately, the results from this present study emphasise that a slow-down in growth is not a reliable indicator of adrenal suppression and that there may be no clinical symptoms. GPs are usually advised that when a child's asthma symptoms are under control they should gradually reduce the dosage (or back titrate) to the minimum level at which ICS is still effective. The authors say that their results add greater evidentiary weight to findings from earlier studies and recommendations that children with asthma should receive ICS at the lowest effective doses.

The take-home message for parents is the need to review the warning signs of adrenal suppression with their child's doctor or asthma nurse. In addition, although the close monitoring may cause practical problems for some time, wherever practical, parents should co-operate fully with programmes to reduce their child's ICS dosage to the minimum effective level.

References

[1] Fitzgerald, D., Van Asperen, P., Mellis, C. et al. (1998). Fluticasone propionate 750 micrograms/day versus beclomethasone dipropionate 1500 micrograms/day: comparison of efficacy and adrenal function in paediatric asthma. Thorax, 53: 656-661.
[2] Patel, L., Wales, J.K., Kibirige, MS.. et al. (2001). Symptomatic adrenal insufficiency during inhaled corticosteroid treatment. Arch Dis Child, 85: 330-334.
[3] Taylor, A.V., Laoprasert, N., Zimmerman, D. & Sachs, M.I. (1999). Adrenal suppression secondary to inhaled fluticasone propionate. Ann Allergy Asthma Immunol, 83: 68-70.
[4] Todd, G.R., Acerini, C.L., Buck, J.J. et al. (2002). Acute adrenal crisis in asthmatics treated with high-dose fluticasone propionate. Eur Respir J, 19: 1207-1209.
[5] Drake, A.J., Howells, R.J., Shield, JP.. et al.(2002). Symptomatic adrenal insufficiency presenting with hypoglycaemia in children with asthma receiving high dose inhaled fluticasone propionate. BMJ, 324: 1081-1082.
[6] Todd, G.R., Acerini, C.L., Ross-Russell, R. et al. (2002). National survey (UK) of adrenal crisis due to inhaled corticosteroids. Am J Respir Crit Care Med, 165: A767.

Wednesday, July 19, 2006

BBC Breakfast Covers Heat Stroke For Humans

Blue sky with intense, glaring sunI've complained about BBC Breakfast's coverage of the heat and its health implications recently, particularly the emphasis on spotting heat stroke in alpacas rather than humans. Well, today, they finally interviewed a talking head GP about spotting heat stroke in very young or elderly people. There wasn't much coverage, but at least they have mentioned the issue! There was far more attention given to the image of a woman's flip-flops stuck in melted tarmac and a lot more attention given to the prediction that today may well be the hottest day on record (records have been kept from 1776, apparently).

Of course, there has been a complete dearth of practical advice for people with heart failure, COPD or asthma. Nor has there been any advance warning that people should be wary of an abrupt change in weather that may involve downpours: the mechanism is not well understood but there are strong indicators that thunder and rain worsen asthma or other respiratory symptoms. Review the self-management plan where this exists and make sure that you keep medication with you at all times. If you do not have a self-management plan, then consult your GP or relevant specialist if you need additional advice about how to manage symptoms or a review of how to spot exacerbations that need extra assistance.

Tuesday, July 18, 2006

EpiPens: How To Use Them Safely

Mosaic of 4 images of beesEpiPens are straightforward to use, as long as you've read the directions. The time for reading the directions is not when you or a relative is heading for anaphylaxis following a bee/wasp sting, or the inadvertent ingestion of peanuts/shellfish/name your allergen.

Allergy Capital offers a good pictorial guide to using an EpiPen efficiently and effectively: it also offers a guide to common mistakes and an illustrated guide to EpiPen Mistakes in Anaphylaxis: what not to do! Both of these are required reading if you or a friend/relative [who] carries an EpiPen. If you have a job/activity where you might be called upon to use an EpiPen for a student/whatever, I would assume that you've had appropriate training in how to use this gadget, how to document the incident, and what to do while waiting for help to arrive.

Let's hope that most of us will know what we should do, but never have to administer an EpiPen.

Monday, July 17, 2006

Paediatric Grand Rounds 1.7 Is Up!

Paediatric Grand Rounds in alphabet blocks with a baby partly concealed behindPaediatric Grand Rounds 1:7 is up, courtesy of Dr. Sethi of Pediatrics.info. Children are not small adults but the full richness of human drama is present. Neonatal Doc recalls the experience of losing the pre-term child born to a mother, addicted to heroin, isolated by her circumstances and grief yet connected to us all by humanity.

We learn a lot about the issues and concerns of raising young children including an overview of how they acquire language and how E. coli spreads among them.

I was interested to learn that, as a sleep aid, diphenhydramine is less effective than a placebo for young children despite its effectiveness with adults. A nice example of received folkloric wisdom being counter to responses in a study.

There are many interesting posts on a variety of topics: there are several perspectives that emphasise the importance of context. Is torture appropriate because it may be a cultural practice, is rudeness OK when it is well-intentioned?

For a range of interesting, challenging and entertaining posts, I commend this Paediatric Grand Rounds to you.

The next Paediatric Grand Rounds is scheduled for July 30 and your host is the excellent Flea. The hosting schedule and previous editions are available in the Paediatric Grand Rounds archive.

Thursday, July 13, 2006

Living Near A Major Road Is A Risk For Asthma In Children

Bronze sculpture of a figure with a migraine by Jose SacalParents like clarity. This does not mean that public health messages have to be over-simplified to the point where they start to lose their value (e.g., somehow the 2nd part of the message, "Back to sleep: but for good development children need supervised tummy time" seems to have been lost). However, the issue of traffic pollution and children's health causes a lot of hand-wringing because some parents take it as a reflection on their own car-using behaviour.

When it comes to traffic pollution and asthma in children, study results have been inconsistent but they are displaying a trend. According to a recent study, Traffic, Susceptibility and Childhood Asthma, children who live near a major road are more likely to develop asthma. There are qualifiers and even puzzling results that lend weight to previous findings by other researchers but the main message of this study is that living close to a main road from early childhood increases the risk of childhood asthma.

The study involved more than 5,000 children aged 5-7. Children who lived 82 yards (75m) from a major road were 50% more likely to have had asthma symptoms in the previous 12 months than children who lived more than 328 yards (300m) away. There was a relationship between higher volumes of traffic on the different roads and the children's rates of asthma.

Previous research has assessed the impact of traffic or traffic-related pollution near children’s homes but this study also evaluated the impact of exposure from early in life. This new research shows that the link is particularly strong among children with no family history of asthma who have lived in the same address since before they were two. The findings indicate that exposure to traffic fumes in early childhood may be a key risk factor for the development of asthma.
The risk of asthma-related outcomes was associated with residential distance to a major road...Compared with those living at least 300 m from a major road, there were increased risks for all three outcomes among children within 75 m. For both prevalent asthma and current wheeze, there was increasing risk with decreasing residential distance to the roadway. Among long-term residents (living since 2 years of age at the same home), risk was increased only among those living within 75 m of a major road...

Asthma and wheeze were strongly associated with residential proximity to a major road. These associations were strongest among children with no parental history of asthma who had lived at the same address since early in life. In this group, the highest risk occurred adjacent to the major road, and risk decreased to background rates at 150–200 m from the road. Larger risks of asthma associated with long-term residence within 75 m of a major road were observed among girls than among boys...

...one possible explanation for the larger effects of traffic exposure in children without these strong risk factors is that other risks, for example, dietary factors, indoor allergens, or other environmental exposures, produced asthma in the high-risk group, regardless of traffic-related exposures. It is possible that, among those with parental asthma or allergic symptoms, there was no additional risk of childhood asthma associated with traffic or that any small additional effect of traffic was undetectable in the high background rate of asthma in these children
Dr. McConnell spoke to the press about this study:
These findings are consistent with an emerging body of evidence that local traffic around homes and schools may be causing an increase in asthma. This is a potentially important public health problem as many children live near major roads.
Asthma UK’s National Asthma Panel reported that 66% of people with asthma say that traffic pollution triggers their symptoms. Asthma UK's Senior Policy & Information Officer, Josianne Roma-Reardon, commented:
Although this is an American study, it confirms previous findings of research by the University of Nottingham in 2001. This found an increased risk of asthma symptoms among children living near main roads.

We know that people with asthma and parents of children with asthma are concerned about traffic pollution. Asthma UK believes that air pollution may well play a part in causing asthma to develop and is actively campaigning for cleaner air, as well as funding further research into this area.
Some of the results are puzzling and the inconsistencies are thought-provoking (why the difference between boys and girls? Why the difference in parental history of asthma?). The generic advice is that if you are moving anyway, you may wish to consider buying a house that is further away from a busy road, if you have young children. However, the public health problem is so significant that there can only be substantial progress in children's health if there are changes to transportation, environmental, housing and social policies. It is unclear that the impact of this research study and others like it is so striking that it would bring about such changes.

Wednesday, July 12, 2006

ICS In Asthma: Yet Again, Children Are Not Small Adults

Young boy using a nebuliserChildren are not small adults. This is one of the reasons that Clark Bartram initiated Paediatric Grand Rounds. This stark fact is a headache for pharmaceutical companies who are frequently criticised for their lack of drugs that are specifically formulated for children and tested on them. Understandably, however, it is difficult to obtain ethical approval for drug trials (or any therapeutic trials) that involve children. There has been a lot of adverse publicity about the effect of anti-depressants on children. There is increasing controversy about the effectiveness of current asthma treatments for children.

Assortment of drugs for childhood asthma: from child's ibuprofen through to Ventolin and PrednisoloneIncreasingly, paediatric pneumologists are saying that children with asthma can not be treated as if they are mini-adults. That message was delivered very clearly by Prof. Bisgaard, professor of paediatrics at Copenhagen University Hospital and head of the Danish Paediatric Asthma Centre, at the 7th International Congress on Paediatric Pneumology that has just finished in Montreal. Bisgaard published one of the papers in the May 11 issue of NEJM that evaluated the effectiveness of inhaled corticosteroid (ICS) therapy in treating and preventing wheeze in babies and young children.
Intermittent inhaled corticosteroid therapy had no effect on the progression from episodic to persistent wheezing, and no short-term benefit during episodes of wheezing in the first three years of life.
Bisgaard observed that "Asthma is the No. 1 cause of hospitalisation of our children in the Western world". He went on to argue that treating children with adult medication is inappropriate at best, and, at worst, a grave mistake because steroid therapy doesn't work for children and can lead to more hospitalisation.

Bisgaard referred to his own research and that of others to support his position that ICS are demonstrably not as effective with children and infants as they are with adults. He noted that asthma is typically researched in adults and the results are extrapolated to children.
But it's just not the same disease as you see in the adult. This is very much a big problem.
Bisgaard made particular reference to the controversy about what to call the common childhood presentation of viral infections with familiar asthma-like symptoms, including breathlessness, feelings of tightness in the chest and wheeze.

Bisgaard emphasised that infants and children with severe asthma need a short course of steroids to control the condition, but he argued that physicians need something else to treat mild, intermittent attacks because that is where steroids are currently failing to meet children's needs.
It's a major mistake thinking that one size fits all.
Prof. Sears from the department of medicine at McMaster University, and research director of the Firestone Institute for Respiratory Health at St. Joseph's Healthcare in Hamilton, Ont. focused on the difficulty of making a definitive diagnosis of asthma in early childhood. Most childhood asthma presents as occasional wheezing.
Is the wheezing viral or the first indication of persistent asthma? Only follow-up will show the evolution of the disease.
He acknowledged that a substantial number of children who have a history of these symptoms do not develop asthma.
How to treat them, if at all, is the kind of questions being answered by Dr. Bisgaard's studies and others.
He emphasised that, despite the difficulties, children must receive the appropriate treatment because asthma alters lung function and has implications for later well-being.
Chronic inflammation can lead to permanent changes in the airway wall, which makes the asthma irreversible.
The conference heard from Prof. Ducharme of the department of paediatrics at McGill University Health Centre and head of asthma research at the Montreal Children's Hospital. She directly addressed the controversial use of high doses of ICS in children: she stated that the treatment is very effective in controlling the condition but it is not a cure, and does not prevent the natural progression of the asthma disease process. Ducharme discussed a study of children with a family history of asthma who had daily steroid treatment for 3 years.
[Steroid treament] works beautifully to control symptoms. It had a preventative effect. But once you stop, it doesn't alter the progression of the disease. Everyone came back to the same number of episodes and severity.
Throughout the world, asthma is now the most common chronic disease of childhood. Asthma is a substantial burden to children, parents, healthcare services and society. Recent research and conference discussions like the above accentuate the need for more research that specifically addresses the care and management of paediatric patients. Amid all the excitement about pharmacogenomics and gender differences in response to medication, these discussions are a timely reminder that although adult studies may suggest a benefit, an agent’s paediatric efficacy can never be be known until research is conducted with children.

Tuesday, July 11, 2006

Grand Rounds 2:42 Is Up!

the bare limbs of a hoar-frost rimmed tree are highlighted by a mixture of fog and sun against a clear blue sky: different elements co-operating to make a striking image
This week's edition of Grand Rounds is hosted and selected by a Transplant Co-ordinator (TC) from Donor Cycle. I am utterly fascinated by the medblog insight into the working lives of people whose jobs make an obvious and direct difference. This week's online peek into the diverse world of medical researchers, healthcare workers, patients and policy makers is as interesting as ever. Like everything else, good medicine relies on techno-stars but depends upon good communication and co-operation. It put me in mind of the above image from Flickr - like everything else, good medicine relies on techno-stars but depends upon good communication and co-operation.

All of human life is there, from why childbirth is like baseball through to the role of bingo and a female posse of friends in helping a widower to remain chipper. There are several splendidly quirky pieces but one of the quirkiest and lung-related is why asthma is like having a beaver in your lungs: it makes sense when you are practising medicine on the tundra.

I commend Grand Rounds to you.

Monday, July 10, 2006

Traffic Pollution Harms Lung Function In Healthy Children: You Hum It, They Live It

Mosaic images of pollution, gas mask and child with nebuliserGlobal warming is an unusual topic for a song, but I offer a musical take on the impact of traffic pollution on lung function in healthy children. Please sing it to the tune of Favourite things from The Sound of Music.









Carbon from traffic decreases lung function;
Fossil fuels smudge up the air with corruption.
FEV, FVC, spirometry
Are showing diminished capacity.

Dark coloured sputum and black macrophages
Clutter the airways but act as good gauges
Of exhaust pipes spewing opacity
Causing diminished lung capacity

Breathing in air that is full of pollution
Leads to kids' general health dissolution
Wheezing their way to co-morbidity
Showing diminished lung capacity

When the car fumes
When the plane flies
When the ozone's bad---
Kids simply breathe with lungs harmed by these things
And their future health's so bad!
Yes, researchers have confirmed what most people have believed for some time. Air pollution, with an emphasis on tiny carbon particles created from fuel combustion in traffic fumes, is working its way into children's airways and diminishing their lung function. Researchers discovered that for every one micrometer-squared increase of carbon content in children's lungs, there is:
  • 13% reduction in forced vital capacity (FVC)
  • 17% reduction in forced expiratory volume in one second (FEV1)
  • 35% reduction in the forced expiratory flow (between 25-75% of the forced vital capacity).
One of the authors, Dr. Jonathan Grigg, is reported to have said that:
[h]igher levels of exposure [to carbon particles] are associated with lower levels of lung function.
Black carbon particles are an acknowledged major component of air pollution. Motor vehicle emissions and fossil fuels are the major sources of these particulates.

The study involved healthy children from Leicester, a city in England that has air quality within an acceptable range according to UK levels. The children were 8-15 years old, had normal levels of physical activity and had been living in their current homes for at least a year. The researchers collected sputum (mucous) samples from the children and assessed their lung function with appropriate tests and spirometry.

Only 64/114 children provided a sufficient sample of mucous to measure the carbon content of the macrophages (protective white blood cells) in the airways. The researchers found that the higher the level of carbon that was detected in the mucous, the greater was the reduction in lung function. This finding remained constant even after the researchers controlled for other variables such as environmental exposure to tobacco smoke, body mass index and gender. Grigg speculates that the most plausible explanation for this diminished lung function is that the particulate matter is implicated in restricting the growth of the children's lungs.

The researchers investigated the possibility that reduced lung function was contributing to an increase in carbon deposits by examining the carbon content of the lungs of 9 children with asthma: children who naturally have diminished lung function when compared to healthy children. The asthmatic children had less carbon in their lungs. Grigg suspects that somehow, people with asthma process the inhaled particles differently than those with healthier lungs, and the carbon is deposited in different cells than the macrophages in the airways.

According to news reports, Grigg stresses that the damage to children's lungs is cumulative.
Particle pollution exerts a small negative effect on lung function growth, but since the effect is continuous, it may have a large negative effect when acting over several years. This study is another piece in the jigsaw showing that air pollution from traffic has adverse consequences.
In a related editorial, Dr. Gauderman observes that the factors that disrupt lung function in childhood are significant because of the lifetime implications of the impairment.
[R]educed lung function later in life has been described as second only to the exposure to tobacco smoke as a risk factor for death.
However, if parents are wondering whether or not they should move away from busy traffic routes, Grigg counsels against it. He emphasises that we can not reasonably avoid particulate pollution. He thinks that the study data are important when considering environmental and social policy and the cost/benefit analysis of less-polluting fuels.

On a related point, there is a push towards encouraging car manufacturers to produce environmental impact labels in their advertising and the running-costs associated with them. This raises the question, "What is a price?". To everyone but economists, it is nothing more that the amount we pay for a given item or service. One example is the amount of money we hand over for our food shopping at the supermarket. But, to an economist, the price is a more sophisticated package. The time that we spend waiting to enter the car-park, at the fish counter, the delicatessen and at the check-out is all part of the price. The food miles accumulated by our purchases are part of the price. According to the economist Kevin Murphy, the nutritional downside of our food choices may be part of the cost: he calculates that a cheeseburger effectively costs $2.50 more than a salad in long-term implications.

What would the true costs be if advertisers had to include health impacts and quality of life for pedestrians, other road users and city inhabitants in their costings? What is the cost/benefit analysis of alternative fuels that reduce the impact on the environment and on children's health?

What would happen if advertisers had to give the true, loaded cost of using their vehicles? Moving beyond even the new fuel economy label to include associated health costs as well as the cost to the environment.

The findings are an interesting addition to the earlier McConnell study. Researchers looked at more than 5,000 children aged five to seven and found that those living 82 yards (75 metres) from a major road had a 50% greater risk of having had asthma symptoms in the past year than children who lived more than 328 yards (300 metres) away.

Like Grigg, McConnell is interested in broader environmental issues and informing social policy.
We conclude that living in a residence with more nearby traffic increases the risk of childhood asthma. Children with no parental history of asthma who had long-term residential exposure (or early-life exposure) constituted a susceptible population, and the risk was larger for girls than for boys. Because a substantial number of southern California children live near a major road, this exposure is potentially an important public health problem that could be remediable by transportation and residential development policy and by more effective control of vehicular emissions. Among those long-term residents with no parental history of asthma who lived within 75 m of a major road, 59% of asthma was attributable to residential proximity to the road.
Grigg is reported to say that on an individual basis, the pollution-linked lung function changes are quite small: this is true, however, the confidence intervals calculated for the study are broad, and, in the case of the FEF, ranges from 11 to 58%. The standard advice for families who live in a high-pollution area and have respiratory symptoms is that they should minimise children's outdoors exposure on high-ozone or high-pollution days. Which all sounds rather bland and ineffectual given the nature of these findings and the lifetime implications for children's well-being. Where is the dream-team of a really smart economist, an epidemiologist and a respiratory specialist when you need one?

Saturday, July 08, 2006

Paediatric Grand Rounds Wants Your Post

Mocked-up Magazine Cover For Paediatric Grand Rounds

Dr. Sethi of Pediatrics Info is the host of the next Paediatric Grand Rounds. He invites your recommendations and submissions for the next issue on July 16.

Please send the posts by Saturday 15 to Dr. Sidharth Sethi of Pediatrics Info:

sidsdoc@gmail.com

You can consult both the hosting schedule and earlier editions in the Paediatric Grand Rounds archive.

Friday, July 07, 2006

A Rough Time For Family Doctors?

side head shot of beautiful boy with eyes closed, mouth closed, calmly just breathingThe irrepressible Flea is the quintessence of resilience as he continues his campaign to provide continuity of care and keep non-emergent cases out of the ED: he discusses a new study in Pediatrics. He sums up the statistics as follows:
Fully 64% of all pediatric ED visits to these hospitals in Toronto were not emergently ill. The authors acknowledge that their findings may not be generalizable to hospitals in the United States. They may be right. The anectdotal reports of my pediatric ED colleagues suggest that the rate of non-emergent visits is higher still in my community.
Flea provides a lot of education in his community but media reporting is not supporting him. E.g., there is a lot of media coverage of the Trautner study that children with a high fever are at risk of bacterial infection and should have a workup. CNN is the only news source that I've seen so far who specify that the high temp is 106F+ rectal. A simplifed version of that message such as "high temp" will probably make a lot of parents very nervous about waiting to see their family doctor or accepting no-testing or a wait-and-see strategy.

Added to the above is an NEJM item on the under-recognised burden of influenza in young children. In the UK there is extensive coverage of a BMJ item on the failure to recognise whooping cough in children (particularly in those who were immunised). The study found that 37.2% of children who visited their doctor with a persistent cough had evidence of a recent whooping cough infection albeit 85.9% of them had been fully immunised. The researchers report that a less rigorous criterion for a positive diagnosis of pertussis would have increased the number of children with a positive diagnosis to 43%. The authors comment on the inevitable speculation that some young children are diagnosed with asthma on the basis of a persistent cough which might more accurately be attributed to whooping cough.
A precise diagnosis is often difficult for the doctor, but parents are anxious for an explanation. Children commonly receive empirical treatment for asthma and may be referred for further investigation. These investigations often fail to yield a clinical reason for the cough, which can last for months.
They do continue the train of thought that some children may continue receiving inappropriate medication and treatment for some time, up until they are old enough to receive standard clinical assessment for asthma, even if that were to happen.
...a secure diagnosis of pertussis will allow general practitioners to give parents an indication of the likely length of cough and prevent them prescribing unnecessary drugs for asthma or referring children for further investigations.
So, according to media reporting on these issues, it seems as if parents can have no confidence in their diagnostic or treatment skills (is it uncomplicated influenza or not?) - but are also being told that they should sometimes question those of their family doctors. I've seen some suggestion that the whooping cought findings are another indication that vaccination is only ever partially successful although the authors plainly state that the clinical symptoms were less severe in the children who had been vaccinated. This is a wretched state of affairs. However, more education and transparency is the only practical solution.

Thursday, July 06, 2006

Food Allergy And Intolerance Testing: Makes Me See Red

Sign text reads: Peanuts and peanut dust everywhereFood allergy and intolerance are sometimes derided as 'populist illnesses'. However, parents are desperate to do something for their ill or distressed children. If they suspect an allergy or intolerance, they have so much difficulty in finding appropriate testing on the NHS that many of them consider mail-order testing that sounds plausibly scientific. The problem is that most of these food allergy and intolerance tests make me see red - I know so many people who have paid out hundreds of pounds for meaningless results.

On an earlier version of his site, Dr. Adrian Morris provided a good summary of the value or scientific basis of these tests.
An Allergy Test should accurately and reliably identify one or more agents to which the patient reacts on each exposure. These allergens must be the cause of the patient’s immune-mediated allergic symptoms. This reaction need not necessarily be IgE mediated, but may involve a T-cell Delayed hypersensitivity reaction or direct Histamine release from Mast Cells and Basophils. The test should be reproducible and identify the implicated allergen on each occasion the test is done. The allergy should be specific to that allergen with minimal false positive test results (when the test is positive in someone with no allergy), or false negative test results (where the test is negative in a person who is known to be allergic to that allergen).
He also reserved his judgement about the value of the YorkTests:
IgG4 antibodies may play a role in food intolerance or IBS, and are currently being evaluated by Allergy UK in conjunction with York Laboratories and further studies will be published shortly.
Visiting the YorkTest site, you will see reference to 1 published study, and the results were not striking. But, I suppose that the rest of the 'evidence' is still in the process of collation and review.

Dr. Morris no longer refers explicitly to the YorkTests in his overview of controversial aspects of allergy tests and testing, but he does quote the abstract of a paper by Wuthrich on Unproven Techniques in Allergy Diagnosis:
Although some papers suggest a possible pathogenetic role of IgG, IgG4 antibody, no correlation was found between the outcome of DBPCFC and the levels of either food-specific IgG or IgG4, nor was any difference seen between patients and controls. The levels of these and other food-specific immunoglobulins of non-IgE isotype reflect the intake of food in the individual and may thus be a normal and harmless finding. The so-called 'Food Allergy Profile' with simultaneous IgE and IgG determination against more than 100 foodstuffs is neither economical nor useful for diagnosis.
Somewhere, I have seen the caution that if you have been avoiding a foodstuff for some time before the testing, there may not be any antibodies/antigens present and your results may therefore contain a false negative. You are counselled, however, that you should not therefore decide to deliberately eat a food that you suspect causes a reaction, just for the benefit of the test.

I'll leave aside some of the issues that really annoy me. But, if a child's parents have been modifying the diet to exclude suspect foods, won't the results be open to the interpretation that they are (very expensive) false negative results? Parents' money is their business: how they feed their child is their business but I would wish that their decisions were not based on a test that has an unproven scientific basis.

I recommend reading an article by Sheryl Miller, IgG Food Allergy Testing by ELISA/EIA What Do They Really Tell Us? I have some criticisms of the article and the source but it does report a useful evaluation of inter-lab and intra-lab reliability, the test subject:
tested reactive in 76% of Lab A’s test (73 positive/96 foods), in 29% (28 positive/95 foods) of Lab B’s test, and reactive in 22% (22 positive/102 foods) of Lab C’s test.
Miller also raises useful questions as to the reliability of the test strata and the challenge substances. Beyer and Teuber offer this useful summary:
The skin prick test and measurement of specific IgE antibodies to food extracts, individual allergens or allergenic peptides are helpful in the diagnostic approach. Food-specific IgG continues to be an unproven or experimental test. The other alternative and complementary techniques have no proven benefit and may endanger patients via misdiagnosis.
If you really think that allergy testing would help your child, ask your doctor if it is possible to have a referral to an appropriate clinic if they do not offer the services at your surgery. It may be very unwise to restrict your own or a child's diet on the basis of scientifically-dubious tests. Restriction might even contribute to later sensitivities for a child if there are no appropriately low-level challenges to the immune system. There seems to be little value in test results that are not grounded in science and may imply the need for dietary-restrications or allergen-avoidance that may have such a significant impact on your well-being or that of a child.

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Wednesday, July 05, 2006

Psychiatrists Admit No Science And No Cures: In A 5 Minute One-Sided Video

Sting for slackers, couched in mail-order scam textA video from CCHR (co-founded by the Church of Scientology) is doing the rounds: Psychiatrists Admit No Science and No Cures. The video is 5 minutes long (an automatic defence against being nuanced), one-sided, it features Thomas Szasz, it semi-ambushes a number of American Psychiatric Association conference delegates/psychiatrists on the street who can have had little idea that the material would be used in this way.

I'm taken aback by the video. No, there is no blood test for it, but if a troubled teen self-harms many times a day, I think there is a mental-health problem. However, the video seems to be anti-psychiatry (perhaps this is not surprising, given its origins). I don't understand what is being offered as a solution. It's all well and good to advise us to say, "Gee, Doc. Where's the test for that?" upon hearing a psychiatric diagnosis for a loved one, but what is that supposed to do? Leave us refusing interventions (pharmacological or not) that might help the putative loved one? Depression does have a well-established mortality rate, doesn't it? Or is there some serious and well-researched disagreement on this point?

As for the sneering cui bono question which Szasz answers with, "The people who make the diagnosis", what? Seriously, it's the psychiatrists, psychologists, social workers etc. who benefit? Nice to see that Big Pharma is implicitly left out of the rogue's gallery for once, although I am sure that they would be in the list of secondary beneficiaries or rogues. I know very little about what the Church of Scientology recommends for diagnoses in which they don't believe, but media reports tend to contain the words vitamins and saunas. I have no idea whether they charge for these interventions, I equally have no idea whether or not they are effective although I have my doubts.

Mental health is a serious issue. Psychiatry deserves more than ambushing delegates on the street and taking their responses out of context. I would like to see a discussion in which psychiatrists tell us what they do achieve: I'd even like to see input from some patients.

Anecdote warning. When I was 9 years old my mother sent me to take something to a neighbour. When I arrived, my neighbour's children were crying in the kitchen: their mother was in bed and refusing to move because she was a nuclear bomb, and if she moved, she would destroy the world. I fetched my mother. Sometime later our neighbour was admitted to hospital. Some weeks later, our neighbour returned home. She no longer believed that she was a nuclear bomb and she was functional again. Cure? Maybe not, because she did need to keep taking some medication. Remarkably improved and functional to the point of being a success story? Absolutely.

I wouldn't feel so strongly about this video if it were not being so heavily promoted among desperate parents who receive nothing but conflicting advice about what best to do for their troubled children. This is the harm of what happens when government destroys its own credibility and betrays the trust of the electorate.

Tuesday, July 04, 2006

BBC's Guide To Hot Alpacas

Blue sky with intense, glaring sunToday, BBC Breakfast kindly took time out of their busy schedule to tell me about the warning signs of over-heating in alpacas, angora goats etc. I know that they pant, lie down, look generally listless etc. and that the best thing to do is to give them water and cool down their heads (possibly with a bucket of water). I've even picked up hints on how to spot over-heating in cats and dogs. Humans? What? Where is the interest in that news story?

If you're going to issue these warnings, do it properly. Don't just refer to other uninformative sources. I'm not asking for film about elderly people struggling to breathe while hooked up to their oxygen, or turning blue from attempting the slightest exertion. But there must be a way to keep these health advisories relatively light-hearted while also being informative.

Of course, worse still is the hand-wave advice to phone your vet/doctor if you are concerned about the hot weather. Really? It's not as if GPs will be coping with an increased work-volume because of sunburn (see Monday's entry of The Crippen Diaries Week 27) or seeing patients who are in respiratory distress etc.? How about, people with COPD, heart failure, [insert chronic illness] should contact their GP if they are concerned or their self-management plan isn't reducing their symptoms: everybody else who needs advice can consult NHS Direct by web or phone, or even television.

It's Summer Health Week on the BBC. Although this material does not have the extensive audience of the Breakfast news programme, I hope that the BBC does cover some more serious heat-related health issues in this programme; particularly as this programme's audience may contain a number of people who are sufficiently disabled by heat to benefit from some timely advice.

Monday, July 03, 2006

WellChild Offers A Children's Guide To Asthma

Young boy using a nebuliserUser-testing is very popular. It means that you test that something works for the people who will be using it. WellChild has provided several guides on a number of health issues: they cover the needs of children, families and health professionals. They claim to offer "age-appropriate material". Certainly, the Children's Health home page is promising: there are lots of friendly photographs of children and adults and some colourful graphics.

However, this is what you find if you select the "age-appropriate" explanation for asthma:
When a person breathes, air travels into the lungs through tubes called bronchial tubes, which branch out like a tree. These branches get smaller until they turn into millions of tiny air sacs called alveoli.
This would be "age-appropriate" for a group of children who would be attracted by the Tweenie-like graphics? Huh?

I am particularly irritated that the site has an accessibility policy but there are many errors on the site where text is presented in the form of bitmapped graphics that have not been given an alt text tag, or have been given a wrong one/and or one that contains spelling errors that would confuse a screen-reader. The charity plainly spent money on the site but may have been so concerned with form over content, that they didn't spend any money on considering whether or not the content was appropriate, nor did they ask for quality testing.

The content is important. Please treat it like it is. If you are a high-profile charity then please test that your material is appropriate for its intended audience.

Heat Health Alert: Too Much Heat Is Not Good For Some People

Blue sky with intense, glaring sunHealth advisories can be both irritating and entertaining. The Met Office's Heat-Health Watch was extensively promoted on the television news this morning. This was alongside light-hearted advice about making swamp coolers by directing a fan to blow over a bag of ice (seriously, they didn't see the episode of CSI where something like that killed someone?).

We have a level 3 alert in much of England and Wales. The advice for this is as follows:
Stay out of the sun. Keep your home as cool as possible — shutting windows during the day may help. Open them when it is cooler at night. Keep drinking fluids. If there is anyone you know who might be at special risk, for example an older person living on their own, make sure they know what to do.
More advice is available from the Met Office and NHS Direct.

Off-hand, this advice seems to be so general that it is ineffective. It would have been useful to see specific advice for people with respiratory conditions (e.g., children with asthma) even it it was as bland as consulting the asthma care-plan. It might even have been helpful to recap some of symptoms of heat-stroke, particularly in young children or older people. If you're going to take up so much time on a national news programme, do something useful with it beyond:
There's a level 3 heat-health alert. Too much heat is not good for some people. Here's some generic advice that probably doesn't match your circumstances but we feel we've made an intervention here and performed a public service.

Sunday, July 02, 2006

Paediatric Grand Rounds 1:6

Photo mosaic reads Paediatric Grand Rounds 1:6Guilt, desperation, fear and magical thinking can be powerful forces in decisions about children's healthcare and their well-being. So can resourcefulness, compassion, love and the intellectual challenge of caring for children whose lives present a rich mosaic of their own needs and circumstances that are determined by others.

Neonatal Doc gently confronts us with a tough question: when is failing to resuscitate a premature baby tantamount to age discrimination? Or an example of negative views of disability? On the latter point, Angry Doc of Singapore is miffed by the guilt-trip Wyeth use to promote vaccination. However, he is confused and angry about the implications of a politically-correct objection to the advertising campaign and wonders where that would leave public health education.

The blogosphere was aflame with discussions of the recent New York Times article about an aggressive public health campaign in support of breast-feeding. It's hard to avoid the feeling that the shock tactics obscured the educational material. Dr. Sarah of Good Enough Mummy strongly objects to the spin of the rebuttal piece by Stats.org that presents an unmitigatedly negative view of breast feeding. Disease Proof emphasises that breast milk is nutritionally, immunologically and developmentally superior. Meanwhile, Amka wonders if we should do more to support public breast feeding.

After a trip down memory lane to the snake-pit-resembling Grand Rounds of his student days, Dr. Jest contemplates a contemporary snake pit in the form of a potential measles epidemic and the media treatment of a group of pro-vaccination doctors. After recent experiences of a substantial increase in workload and parental alarm caused by an outbreak of a comparatively trivial illness, he wonders about the impact of something that is considerably more than an inconvenience.

The irrepressible Flea is the quintessence of resilience as he urges us to ignore disarmingly dangerous advice and continues his campaign to keep non-emergent patients out of the ED. Recent events at work have prompted Dust in the Wind to think about the letter that she would like to hand to parents when they arrive in the Emergency Department with their child, What not to say.

Does Dr. Megan dream of a similar letter that addresses, What not to do? In The World According to Megan, we learn that some parents have a cavalier approach to administering antibiotics to children, and unerring confidence in the rightness of their actions. Meanwhile, the incredulous paediatrician has a spinning head and a mass of concerns that is not addressed by ad libitum amoxicillin.

Awesome Mom recalls a time when advice from her son's specialists undermined her confidence in her decisions, judgments and actions. She is grateful to her paediatrician who took time to listen to her fears and made her feel competent again.

A lot of factors play a part in parents' decision-making when their children are desperately ill. But with a heavy heart, Orac knows that the reality of illness is stronger than magical thinking. Sometimes, we want a happy ending but it just isn't going to happen. A surprising number of PGRphiles name The Princess Bride as one of their favourite films or make regular references to it. When VitaminK MD quotes the Dread Pirate Roberts, "Life isn't fair, princess, and anyone who tells you differently is trying to sell you something", we are in for a moving account of just how unfair life can be.

Matthew Baldwin of Defective Yeti writes with skill and humour about his many interests, and his life with his wife (aka, The Queen) and his son (aka, The Squirrelly). In an unexpected post, we discover what it was like for this family to discover that The Squirrelly has a diagnosis of Autistic Spectrum Disorder (ASD). Read through to the end to discover the surprising link between love and horseradish.

Matthew mentions his concerns about the availability of appropriate resources and schools for children with ASD or similar disorders. Clark Bartram of Unintelligent Design gives us a horrifying glimpse into the practices of one school in New York that uses extreme measures that amount to state-funded child abuse.

It is easy to agree on some common features that harm or promote the development of children. Building a better brain argues that science supports the need for social policies to support strong, stable relationships between children and key figures in their lives. Stress and negative life events do play a significant role in children's well-being, even being implicated in asthma exacerbations. However, the UK experience of social interventions is dispiriting. An evaluation of programmes that exist to boost children's welfare through improving parenting skills and creating a secure and happy home environment indicates that they may be disadvantaging some of the children who need them most.

Have you ever paused in the midst of your childcare chaos to wonder how blind parents cope with the same situations? Well, Charv tells us what it is like for her as a blind, stay-at-home mother to care for three young children without resorting to bells or tagging - yet.

Tagging teenagers has a lot of support in some of the UK press. Dr. Jest knows that one sure sign that he is in for a rough few minutes is if a shoe-gazey teenager turns up for an appointment, flanked by both parents. Is this similarly true in other countries? girl MD continues her occasional series about classic parent phone calls: this one is about an indelicate teenage problem that definitely did not require ED attendance.

The Granola sounds like she was a smart teenager. She traces the origins of her scepticism about alternative medicine to her teenage encounter with a chiropractor who seems to have been playing a cynical numbers game.

Finally, an interesting corollary of the truism that children outgrow shoes and clothes quickly: have you ever thought that the same is true of pacemakers? Dr Hsien-Hsien Lei looks at early research into biological pacemakers that would be maintenance-free.

This is the 12 week check-up and Clark Bartram's baby is bouncing with vitality and developing well. You can consult both the hosting schedule and earlier editions in the Paediatric Grand Rounds archive.

The next Paediatric Grand Rounds is scheduled for July 16 and your host is Dr. Sethi of Pediatrics Info.

I'd like to thank all of the contributors who have so generously shared their posts with me. I look forward to seeing you in future editions of Paediatric Grand Rounds.

For more information about the images used in the illustration, click on it or visit the detail on Flickr.