Thursday, November 30, 2006

Got Asthma? Thought About Inviting A Few Hookworms To Move In?

Toddler kisses a cheerful looking pigSo, it's your first kiss and several questions might come to mind:
  • Is it the right time?
  • Is anyone watching?
  • Does your partner even want to?
  • Is your breath fresh?
  • Then you lean in and just go for it!!!
  • What's the hygiene hypothesis?
PCS of Adirondack Musings has a good overview of Asthma Epidemic (and Hygiene Hypothesis): recapping the NYT piece based on a recent NEJM paper on The Asthma Epidemic. PCS is a trifle vexed that a lynchpin of the hygiene hypothesis is overlooked:
Chronic infestation with helminths may also confer protection, but short-lived episodes of infestation may exacerbate atopic disorders.
Now, there was an interesting sidelight on the hygiene hypothesis earlier this year with the Increased Levels of IgE and Autoreactive, Polyreactive IgG in Wild Rodents study which is well summarised in From Good Hygiene Comes Bad Allergies. We also learned that 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 reported that 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, as I admitted at the time, I have nothing on which to base that doubt apart from prejudice.

I was intrigued and repulsed in equal measure when I came across an anecdote by Luckbeaweirdo who claimed to have cured his severe asthma and hayfever by using hookworm. He didn't pull any punches about what happens during infestation:
Walking barefoot in soil contaminated with feces (the source of hookworm eggs/larvae) is the most common method of exposure. The other is inadvertent ingestion of contaminated feces. Note that the hookworm cannot proliferate in your gut, you can only increase your infestation level by coming into skin contact with larvae or ingesting contaminated feces. After skin penetration, the venous circulation carries larvae to the pulmonary bed, where they lodge in pulmonary capillaries. Within 3-5 days, the larvae break through into alveoli and travel up the ciliary escalator from the lungs into the bronchi, the trachea, and the pharynx. This often causes a violent cough such as I experienced. It woke me up, continued for about two hours and was so violent at its peak that I vomited into my mouth. Upon reaching the pharynx, larvae are swallowed and gain access to the GI tract. Once in the GI tract, worms attach to the wall of the lower intestine and begin to feed on the blood of the host. They are intestinal leeches.
He helpfully describes the practical method that he has devised to reinfest himself without having to return to Cameroon. I have refrained from quoting any of the most gruelling parts of this interesting piece but thought at the time that few people would be desperate enough to run the risk of collateral infestations and infections from acquiring hookworms, almost literally, in the field.

Now, the BBC has publicised a call for volunteers for a hookworm study in the UK. Researchers are trying to find out if they can use the hookworms or their products to lesson the impact of allergies, asthma or hayfever. I have previously wondered if the rise in the prevalence of asthma and allergies in Africa is linked to improved sanitation and less exposure to helminths. Professor John Britton is leading the research and has previously reported that, in Ethiopia, people living in the countryside are less likely to have allergies but more likely to have parasites.
We found higher levels of asthma in the towns and we believe this was partly down to a lower number of people carrying parasites.
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. It is logical to consider that 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. However, I must still confess to queasiness in the matter, despite the rationality. We have to use helminths to distract an over-sensitive immune system? We can't just play it show tunes and smile fetchingly?

The mechanism by which the hookworms are thought to 'distract' the immune system is not well-understood but I can understand why people who have life-threatening allergies or asthma would consider what seems like extreme measures.

Tuesday, November 28, 2006

Paediatric Grand Rounds Wants Your Post, Please

Mock-up cover for Standing Baby magazineYes, it is out with the begging bowl, as I shamelessly rattle the post collection bag and ask you for your contributions to Paediatric Grand Rounds. As you can see from the magazine cover, we are open to conventional and more off-beat topics.

The next edition of the PGR is fast approaching and will be hosted at The Granola Rules this Sunday, December 3. Ami asks that your submissions should be sent along by
Deadline: Saturday Dec 2 at 10:00 pm Mountain Time, which is 12:00 am Eastern Time, Sunday 5:00 AM Greenwich, and Sunday 3:00 pm in Melbourne and Sidney.
You can read about Ami's suggestions for PGR and email your PGR submissions to Ami using: ami at geekatplay dot com.

Clark Bartram is looking for hosts for future PGRs. You can consult both the hosting schedule and earlier editions in the Paediatric Grand Rounds archive.

For more information about the image used in the illustration (from Tedsblog), click on it or visit the detail on Flickr.

Monday, November 27, 2006

What Is It That You Do When You Work With Children?

3 baby hedgehogs nestled into a handPeople sometimes ask about what we do when with work with children. Changing names and various other details, one story is as follows.

Chris was a 9 year-old boy with asthma. He had been diagnosed with asthma at the age of 18 months and had been using reliever, preventer and combination medications for many years. He regularly had severe exacerbations and was hospitalised once or twice a month. He had at least one exacerbation most nights of the week. He had poor quality sleep, Even when he did sleep, it tended to be fitful and he had a tentative diagnosis of Restless Legs Syndrome amongst others although he had never had a formal sleep study.

We'd spoken with Chris' GP during the week. This is always slightly nerve-wracking, depending on how the GP feels about CAM. Fortunately, this GP had met other GPs who teach the same breathing techniques as we do as part of their NHS practice and he'd read through the summaries that we had provided. He was also mindful that the family was rigorously compliant in following the medication schedule for Chris yet he was on high doses of medication and having regular exacerbations. I met the family for their first session on a Friday evening. Chris had been kept in hospital overnight on Monday after an episode in school and this had pushed the parents into travelling to London to work with us.

Chris was significantly smaller than his siblings although they were younger by 3 years. He had a carrier bag full of his medications, inhalers and spacer devices and a separate bag with a box of tissues. The perfunctory handshake indicated that Chris had cold, clammy hands. He had a matt-grey pallor to his beautiful olive skin, and his eyes were lifeless, despite being dark, large and heavily-fringed with lashes. Further observation wasn't practical because he was wearing a hoodie, with the hood up. I prefer to get as much of the medical history as I can from the child so that I can watch the breathing and posture when he talks, but Chris had other ideas. He slumped in his chair and answered my questions in monosyllables.

Even so, it was obvious that Chris had a very blocked nose and was a mouth-breather. Part-way through the history taking I gave him an exercise designed to clear his nose. With ill-grace, and much encouragement from his parents, he did the exercise and was sullenly surprised that it worked. I asked him to repeat it if his nose blocked again and to keep doing it as often as required. I also asked him to close his mouth and breathe in and out through his nose as much as was practical.

We drew up Chris' first set of exercises, based on his history and condition, and we went through them with him 3 times for one exercise set and then repeated the exercise set after a rest. In between the exercise sets, we played with bubbles and all of the children had to burst as many bubbles with different parts of their bodies as possible.

Chris had a persistent cough. We explained that coughing irritates the airways and reinforces the cough. We worked on two different ways of suppressing a cough. We agreed that if he had a productive cough, he should cough the mucous into his mouth and then remove it gently, rather than cough it out, wherever possible.

We reminded Chris and his parents about continuing to take his medication and, by pre-agreement with his GP, emphasised that he should only take his short-acting reliever medication as needed, rather than on a pre-determined schedule. We drew up a timetable of how many exercises he should do, and how often before we were due to meet again on Saturday morning. We went through the sleep routine (e.g., raising the head of the bed, sleeping on his side etc.) and arranged our next appointments

We went through exercises sets on Saturday morning and scheduled more for him to do before we met again in the late afternoon. Chris was making good progress with his exercises although he was still difficult to engage with - in contrast to his brother and sister who were chattering away, running around the room, picking up various objects, asking questions, talking about their grand-parents and raiding the fridge.

We met again later on Saturday, and then twice on Sunday. Chris had done his exercises diligently, and his (delighted) parents reported that he had used only one puff of reliever since Friday night - he typically used around 20 a day. Partway through the first session on Sunday, Chris was finally warm enough to unzip his hooded top. He was chattier and willing to respond to questions or conversational openers. When his mother was out of the room, we were talking about favourite foods and he told me that no-one had lived until they had tasted his mother's lasagne or her Greek sweets. His father overheard him and told his mother, whereupon she burst into tears because she was pleased to see him being sociable and she had no idea he liked those dishes so much.

When the family arrived for the final session on Sunday, Chris took his hood down. His eyes were brighter and his skin had lost his pallor. His handshake was warm and dry, indicating better circulation. Chris' coughing frequency had reduced substantially but we didn't want to remind him of it by mentioning it. Chris breezed through his exercise sets although we increased their length. We planned out Chris' exercise schedule for the coming week and arranged for follow-up chats on the telephone. We gave careful instructions about Chris' activity level. He should take a brisk walk everyday for 20 minutes, matching his pace to his breathing and build up from there.

In between raiding the fridge, playing with bubbles, and listening to my husband tell stories, the younger children were simmering with excitement about something, but we didn't know what it was. Chris had gathered up his belongings and was about to walk through the door when he turned and said, "I don't know if anyone mentioned that I haven't slept through the night since I was 2". We nodded and waited. "Well, Friday and Saturday I didn't wake once. Thank you." By the by, that's one of the most heartening comments that anyone's ever made to me. So, it's fair to say that we were all quietly gratified.

Chris' progress was so good that we were surprised to get a phone call in the wee smalls of the next Thursday morning. Chris had woken up with an episode of wheezing. The mother had helped him take a puff of Ventolin with his spacer and then phoned us. They did a set of exercises together and his wheezing cleared. I reminded them about how to manage a coughing episode. I was pleased that the symptoms cleared quickly but disappointed that he'd had this setback but Chris' mother had a small confession.

Chris had been feeling so well and energetic, that for the first time in his life, he had played badminton that Thursday afternoon. He'd played for more than an hour. As sometimes happens, he didn't have breathing problems at the time but they had started some time later. It is common for people to feel so much better that they deviate from their recommended schedule and start trying to do too much.

Chris followed his programme and increased his activity level gradually. One month later when we met for follow-up, he was as curious and active as his siblings. He continued to sleep through the night without asthma exacerbations and he stopped being restless. With the support of his GP, and guided by his symptoms, he stopped taking his long-acting reliever. At the 3 and 6 month follow-ups, Chris had good colour and was still lively.

Chris and his family have been diligent about following the programme. His GP and consultant had been very supportive of him trying other techniques as an adjunct to his treatment. Over time, Chris' reduction in symptoms meant that his consultant was happy to step-down his preventer medication. 15 months on, Chris plays football at school. He goes out for long bike-rides with his brother. He hasn't needed to be admitted to hospital since the time before coming to see us. He has adjusted well to the transition to secondary school.

PS - If you followed a link to this, you will only see the comments in Blogger, there are several more in Haloscan. All of the comments' window will load from this message.

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

Tuesday, November 21, 2006

Rodent Hypersensitivity in Inner-City Asthmatic Children

I keep an eye out for new products in my local supermarket. Some new products are sign-posts of social and environmental changes. After years of a limited range, the fruit and vegetable section and delicatessan now reflect the many nationalities that make up this town. Last year, I noticed that the household section now carries several mouse and rat traps and poisons.

Domestic vermin is a wretched problem. If you live in flats or terraced houses, you may find it almost impossible to eradicate the problem if your neighbours are infested. Vermin are almost as bad as neighbours for respecting boundaries. Local Authorities faced with spending cuts have scaled back on some of their environmental work and the rat population is flourishing in my local area. The scale of the problem is exacerbated by the introduction of the land-fill tax which has encouraged fly-tipping by businesses and homeowners and contributed to more infestation.

A conference poster* recently reported on a small-scale retrospective study
They found that 31.5% of patients were sensitive to mouse allergens, and 18.5% were sensitive to rat allergens. Among the patients with mouse sensitivity, 24% had allergic rhinitis without asthma, 30% had mild asthma, and 50% had moderate-to-severe asthma.
Although the results need to be scrutinised as subjected to peer-review publication, the results of this study are in line with those of other similar surveys. The authors claim that although mouse and rat allergens have been amply validated as sources of occupational asthma, it is only comparatively recently that they have been acknowledged as potential triggers in the home. If my area is anything to go by, that would seem to track environmental changes: I would suggest that more people are exposed to mouse and rat allergens, both at home and in public places. I can only think that this casual environmental exposure is going to increase as more Local Authorities move towards a refuse collection of once every two weeks, rather than the present weekly schedule.

The study does highlight the necessity to include rodents in the allergic evaluation of children with moderate-severe asthma. It also brings to mind the recent US report that lawyers can sometimes be more effective in controlling asthma than doctors when they succeed in forcing landlords to renovate their properties or hire pest control.

In the UK, of course, this is ignoring the paucity of appropriate clinical testing for allergies on the NHS and the dearth of available immunotherapy.

*Source: Hemmers P et al. "The Prevalence of Rodent Hypersensitivity in Inner-city Asthmatic Children." Poster 111, presented Nov. 11 and 12. The American College of Allergy, Asthma & Immunology.

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

Sunday, November 19, 2006

Paediatric Grand Rounds 1.16 Is Up!

Toddler kisses a cheerful looking pigSo, it's your first kiss and several questions might come to mind:
  • Is it the right time?
  • Is anyone watching?
  • Does your partner even want to?
  • Is your breath fresh?
  • Then you lean in and just go for it!!!
  • What's the hygiene hypothesis?

Tara Smith is the host of this week's Paediatric Grand Rounds 1:16 and it is an excellent read.

Tara has given me serious heebie-jeebies before now with her engrossing but somewhat gross posts about how E. coli spreads among children and the discussion about why biofilms may answer the question as to why ear infections are so resistant to antibiotics.

PGR is always such a mix of homebrew remedies such as using a hair-dryer for lice control and fascinating advances such as haplotype screening for genetic disorders.

There is a thoughtful crops of posts from parents of children with a range of conditions: some have tentative stories of improvement, others of a gradual decline. All of them are remarkable.

Clark Bartram is always on the look out for new hosts for Paediatric Grand Rounds. You can consult both the hosting schedule and earlier editions in the Paediatric Grand Rounds archive.

PGR 1:16 is a fascinating collection of posts and Tara Smith is to be commended for it. The next host of this carnival is The Granola Rules on December 3rd. Make a note in your diary now and start thinking about your next PGR submission.

Friday, November 17, 2006

Will Probiotic Supplementation For Newborns Protect Them From Asthma?

Mosaic of images of young children with asthma, blocked nose, breathing well or playingPoliticians in California, including Governor Schwarzenegger, have put the needs of children with asthma on the political agenda several times. Asthma is a critical public health issue in California. The UCLA Center for Health Policy Research reports that for children aged 1-17, the number diagnosed with asthma rose from 14.1% in 2001 to 16.1% in 2005. For adults, the number diagnosed with asthma rose from 11.3% in 2001 to 12.7% in 2005.

Researchers at UCSF have launched a study to evaluate whether active probiotic supplements can delay or prevent asthma in young children. The rationale for the intervention is grounded in the hygiene hypothesis. The suggestion is that our prevailing standards of hygiene lead to a lack of contact with bacteria in early life. Similarly, the hypothesis suggests that children have less exposure to viruses. The reduced opportunities for challenge compromises the robust development of an immune system that is protective against the development of asthma and other allergic diseases. Children who are born to parents who have asthma are thought to be particularly at risk.

It is axiomatic that clean water and high standards of food hygiene protect children. Nobody would suggest that children should be exposed to harmful microbes.

As Dr. Wiess, Professor of Medicine at Harvard Medical School, wryly remarked in an editorial for the New England Journal of Medicine:

Eating dirt or moving to a farm are at best theoretical rather than practical clinical recommendations for the prevention of asthma...However, a number of environmental factors are known to be associated with a lower incidence of allergic disease early in life...The challenge will be … to determine the extent of exposure that will ensure safety and have the desired outcome—the development of a healthy child with a very low risk of autoimmune disease.

The researchers have selected probiotics that are found in a wide range of foods such as yoghurt. Probiotics are live micro-organisms that are consumed in sufficient quantities to confer beneficial health effects. Probiotics are intended to encourage the colonisation of beneficial bacteria that inhabit the gastrointestinal system.

Researchers have successfully isolated several strains of Lactobacilli in human breast milk. Further analysis indicates that these Lactobacilli may offer anti-infective protection in Neonates.

The UCSF researchers have selected to investigate whether the administration of Lactobacillus GG supplements 'stimulates' the immune system: the study is Trial of Infant Probiotic Supplementation to Prevent Asthma, (TIPS). The study will involve 280 healthy full-term babies with either a mother or a father with asthma. For the first six months of life, half of the babies will receive a once-daily dose of active Lactobacilli GG and the other half will receive a placebo.

The babies will be monitored for three years with 6 follow-up visits. Researchers will collate and evaluate the data to see if supplementation prevents or delays the the early onset of asthma.

Earlier this year, researchers in Finland published a study about probiotic intervention in neonates. The babies received either the probiotic or a placebo for 6 months from birth. The researchers monitored the faeces of infants at 6 and 12 months to assess whether the Lactobacilli were present. They reported that although they did not find permanent establishment of the bacterium, they did find transient colonisation at 6 months of age. However,
the presence of the strain at the end of the administration period was correlated with a reduced prevalence of atopic eczema later in life.
The TIPS study is still recruiting women who are pregnant and have a history of asthma or a partner with asthma to participate in the study.

It is annoying that TIPS has a website but does not give details of what they shall be monitoring in the infants. They do say they will monitor the children for early signs of asthma.
Some of the early signs include: frequent wheezing, wheezing without a cold or the flu, frequent “runny” nose, and eczema. There are also immune system signs that are sometimes associated with asthma.
I'd have liked to see some detail about whether the TIPS researchers will investigate whether Lactobacillus GG colonises the guts of the infants. And whether this presence/colonisation is positively linked to a reduced prevalence of asthma symptoms at the age of 3. It is possible that some of the infants will be responders or non-responders to the supplementation. It is possible that the babies will have different levels of Lactobacilli depending on whether or not they were exclusively breast-fed, and for how long. Similarly, there may be different levels in babies who received colostrum which can help to establish friendly flora in the neonate digestive tract. So, there will be a number of sub-groups within this small study that will add to the difficulty of interpreting the results with confidence.

It would be useful if the researchers had stated how they will monitor the children for asthma. Although many children are being treated for asthma, and in accordance with their symptoms, it is not practical to confirm a diagnosis of asthma in young children. Diagnosis depends on spirometry, and that is not practical for use with the under-6s. The FDA has approved a new test for asthma that is suitable for children as young as two but this test is not widely available.

A previous study of the effect of long-term conumption of probiotic milk on infections in children attending day-care yielded modest results.
Lactobacillus GG may reduce respiratory infections and their severity among children in day care. The effects of the probiotic Lactobacillus GG were modest but consistently in the same direction.
Nonetheless, Lactobacillus GG supplementation for Neonates is an attractive intervention that is probably cheap and easy to administer. TIPS may also be another way of studying the vexed question of whether exposure to antibiotics in early life is linked to childhood asthma.

FACT (Focus on Alternative and Complementary Therapies) recently published: Probiotics: targeting the paediatric population to reduce antibiotic consumption and resistance (not available online). There is widespread concern about the public health problem that is posed by antibiotic resistance but there is little evidence that probiotics are effective as primary therapies for disorders or as adjunctive treatments (e.g., to re-colonise the GI tract during the use of antibiotics).

The NASPGHAN Nutrition Report Committee recently published an overview of the use of probiotics in paediatric health care. The authors offered
a review and evaluation of the evidence or lack thereof to support a beneficial effect of probiotic agents in a variety of pediatric conditions and to review the safety and potential adverse events that may be encountered when using probiotics.
The Committee emphasised that although probiotics are widely available in many countries, they are:
highly heterogeneous with differences in composition, biological activity, and dose among the different probiotic preparations.
The Committee also noted that for some specific conditions, probiotics may contribute to clinical deterioration. It is important to note that the researchers are implictly using a certified active source of Lactobacillus GG with standardised doses. This experiment can not be tried at home. There is no clear understanding of the mechanisms by which probiotics may modulate various physiological functions. There are no accepted therapeutic doses, no specific recommendations of strains for particular therapeutic actions, no approved guidelines for frequency, or the duration of treatment for different probiotic strains.

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

Wednesday, November 15, 2006

Paediatric Grand Rounds Wants Your Post, Please

Mock-up cover for Standing Baby magazineYes, it is out with the begging bowl, as I shamelessly rattle the post collection bag and ask you for your contributions to Paediatric Grand Rounds. As you can see from the magazine cover, we are open to conventional and more off-beat topics.

The next edition of the PGR is fast approaching and will be hosted by Tara Smith at Aetiology this Sunday. She asks that your submissions should be sent along by Saturday afternoon to aetiologyATgmailDOTcom

Clark Bartram is looking for hosts for future PGRs. You can consult both the hosting schedule and earlier editions in the Paediatric Grand Rounds archive.

For more information about the image used in the illustration (from Tedsblog), click on it or visit the detail on Flickr.

Tuesday, November 14, 2006

Sleep-Disordered Breathing, Mouth Breathing and Quality of Life

Baby asleep; mouth slightly open, poster titled Perfect Moment
I'm british, so please overlook my frequent use of the word interesting. I have a strong interest in children with sleep-disordered breathing (SDB) so I've just looked through the abstract of an interesting paper on Factors affecting quality of life of pediatric outpatients with symptoms suggestive of sleep-disordered breathing.

The authors examined several factors in SDB and children's quality of life. They report the following:
The most common clinical findings was mouth breathing (41.2%). Tonsillar hypertrophy (>/=3+) was found in 62.7 and 52.9% had adenoid-nasopharyngeal ratio greater than 70%. Overweight/obesity were found in 35.3% of the patients. OSA-18 scores ranged from 22 to 85. Tonsillar hypertrophy was significantly related to QOL (p<0.05). Adenoid hypertrophy had trends towards impact on QOL (p=0.094). Mouth breathing correlated well with QOL (p<0.01).
We know from previous research that habits such as habitual mouth-breathing during the day may be clinically relevant in conjunction with other symptoms for severe obstructive sleep apnoea. The prevalence of mouth-breathing strongly supports my own anecdata working with children with SDB so I was pleased to see this.

Swollen tonsils and adenoids are common in children with SDB so I was intrigued to that the authors found that tonsillar hypertrophy was significant but not adenoidal hypertrophy in the population that they looked at. It was a contentious review in places but Gross and Harrison gave a common description of the consequences of mouth breathing in their discussion of tonsils and adenoids:
Mouth breathing presumably causes changes in facial growth patterns as the tongue is placed in an abnormally low position to expand the oropharyngeal cavity. Over time, due to altered vectors of force on facial development, the child develops a long and narrow face, a narrow upper jaw, steep palate, and open bite deformities. This classically is referred to as "adenoid facies".
Adenoid facies are further reviewed and discussed in Adenoid Facies and Nasal Airway Obstruction.

I'm going to be a little persnickety and say that although the authors declared that their objective is:
[t]o determine the relationship between causative factors of sleep-disordered breathing (SDB) and quality of life (QOL) of children who presented with SDB
they should not claim that they are looking at causative factors. Previous studies have reported strong correlations for some of the factors but I can not accept that they are established as causative. Kotagal and Pianosi published an excellent review of Sleep disorders in children and adolescents earlier this year and it is clear that there is much uncertainty about what may be considered as causative. As for the discussion on adenoid facies and nasal airway obstruction, the sequence of events is not clear.

Wherever possible, encourage children to breathe through the nose. Nose-breathing is a useful part of re-training the breathing of children. Maddeningly, I have colleagues in other countries who report that they have worked with children with adenotonsillar hypertrophy that has been documented in scans. They have worked with the children to re-train their breathing and when those children have returned for scans, their hypertrophy has been significantly reduced. Anecdotes are useless however; at the bare minimum, we need to see these examples published in a case series.

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

Sunday, November 12, 2006

Follow Up to Precautionary Principle

Picture of little girl given coloured and Warhol treatment

Clark Bartram has posted a robust piece on Baby Brains and Environmental Chemicals that discusses the coverage of the Lancet Precautionary Principle study I complained about recently. CB sums it up:
What the authors fail to mention, and they aren't alone by a long shot in doing so, is that children are exposed to considerably lower amounts of environmental chemicals than in the past. Furthermore, there is just not much evidence that the chemicals in question, aside from the ones already of concern to pediatricians such as lead, do effect [sic] children in a different way than adults. But more importantly there is no evidence of the "pandemic" of effected [sic] chilren [sic] that the article mentions.
The Times also restores some much needed scepticism about the evidence behind the asssertions.
There is no real reason to believe that chemicals in general are more dangerous to babies than they are to adults. Gestation is a dangerous time, so evolution has given us mechanisms to protect the foetus and the developing brain. According to Professor Alan Boobis, a toxicology expert from Imperial College, studies have shown that the foetus is not systematically more sensitive to chemicals that affect the brain than adults. He adds that the tests in use do not underestimate the risk.
The Times questions the claim that there is “a silent pandemic”. Professor Nigel Brown, a developmental toxicologist from St George’s, London University, commented to The Times that this claim is
a gross overstatement. It is possible there is a problem. We should. study the problem, but there is currently not a shred of evidence of a pandemic.
I do wish that reviewers had better evidence behind their claims of ruination and pandemics. I loathed Michael Crichton's State of Fear but I have some sympathy with this viewpoint:
Has it ever occurred to you how astonishing the culture of Western society really is? Industrialized nations provide their citizens with unprecedented safety, health, and comfort. Average life spans increased fifty percent in the last century. Yet modern people live in abject fear. They are afraid of strangers, of disease, of crime, of the environment. They are afraid of the homes they live in, the food they eat, the technology that surrounds them. They are in a particlarly panic over things they can't even see-germs, chemicals, additives, pollutants. They are timid, nervous, fretful, and depressed...Remarkable! Like the belief in witchraft, it's and extraordinary delusion-a global fantasy worth of the Middle Ages. Everything is going to hell, and we must all live in fear.


If it is not all right to falsely shoult 'Fire!' in a crowded theater, why is it all right to shout 'Cancer!' in the pages of The New Yorker? When that statement is not true?
It was one thing for concerned researchers to alert parents to an environmental danger but it should certainly have a strong evidence base before warning of developmental damage or pandemics.

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

Saturday, November 11, 2006

Car Restraints and Children: A Disagreement Among Friends

Recently, my unbelievably mild-mannered husband had a row with a family friend. The family dropped in to visit as a surprise and, after a cup of tea, the husband left with their car. I will draw a veil over the rest of the visit that involved a lot of unpleasantness about the fact that we wouldn't drive the children on a day out in our car. We like the family - the children our great fun. But-and it's a big but-since the change in legislation in the UK in September, we no longer have the appropriate car seats for young children.

My husband flatly refused to drive anywhere with the children: I supported that decision. The mother wouldn't countenance choosing a place to visit that was accessible by train: she was very loud about it. The mother told us that she trusted our driving and that if she was willing to take the risk then it wasn't our problem. We tried to talk the mother into walking to see some films at the local cinema which is less than a mile away: she refused. My husband's voice was very low and very firm but he was unmistakably angry. Our friends are not talking to us. We are truly sorry about that but we will not drive children without the right seats and restraints.

The video is pretty upsetting but the demonstration with the crash dummy is a convincing argument as to why children need appropriate restraints when in a car. The Miller family give an account of the accident that killed their son:
My son was killed in a car accident last year because a senile, 78 year old woman ran a red light and hit us causing us to flip into a ditch. Kyle's seatbelt came unlatched during the roll and he was ejected. His seatbelt was later examined by several experts who determined it was faulty and told me that seatbelts regularly fail, especially in roll over accidents. I had no idea that seatbelts could fail and think that this is something everyone should be made aware of.
You never expect to be in a car accident and put these things to the test but you still have to take the appropriate precautions. I'd rather not have disagreements with friends and family but I won't compromise on this unless it's an emergency. Nonetheless, I have to admit that part of me feels that it is going to crimp social spontaneity if other people's children are involved. On balance, I'd rather live with the bad feelings than regrets that we didn't do the right thing.

Thursday, November 09, 2006

I Think This Is Overblown But I've Just Discovered That I've Got A Depressed IQ

Modern life damages childhood
Before you read any further, you should know that my mother was of the generation that smoked during their pregnancies and beyond. She was also one of the women who was advised to drink two bottles of stout a day for the added vitamins and iron (the recommended brands were Guinness and Mackeson's Milk Stout as it was charmingly and healthfully, known). My mother had a recurrence of tuberculosis when she was carrying me so I was bottle-fed. I was also taken away from her for some months after the birth so that she could recover from the TB. So, I was isolated for long stretches of time with little environmental stimulation.

If the above were not sufficient to convince me that I shouldn't chew gum and cross the road at the same time, the Lancet has just published a lively paper entitled, A precautionary approach should be taken to protect pregnant women and children against industrial chemicals (no entry in Entrez Pubmed as yet). Among many other portents of the doom and gloom that one associates with the precautionary principle, I discover:
Almost all children born in industrialised countries between 1960 and 1980 were exposed to substantial amounts of lead from petrol that could have reduced the number of children with far above-average intelligence (IQ scores above 130 points) by more than 50% and might likewise have increased the number with IQ scores below 70.
So that's me. Off to the compost heap where I will eat worms because I can't think of what else to do with my life.

To quote from the less than measured account of this article, with the bias-free headline, Danger: chemical hazards
The point that Grandjean and his co-author Philip Landrigan, from the Mount Sinai School of Medicine in New York, want to make is that we know very little about the damage we could be doing to our babies' brains when we expose ourselves and them to modern cleaning fluids, cosmetics, pesticides, glues, plastics and other modern necessities made with potentially hazardous chemicals.

And they believe that there may be already evidence of what these chemicals are doing to us. Neurodevelopmental disorders, for example, appear to be rising, they say, although they acknowledge this is controversial. Many doctors argue that we are simply better at diagnosing them. But certainly more cases of autism are being detected than before. And it is the same with attention deficit disorder, Grandjean and his colleague add. Cerebral palsy is now common.
With the greatest respect, I thought that the prevalence rate for cerebral palsy had not altered much in the last 40 years.
Cerebral palsy is the most common physical disability in childhood, occurring in about 2-2.5 per 1000 children born. The frequency of cerebral palsy has not changed over the last 40 years, despite a fourfold drop in both perinatal and maternal mortality. In some countries there is an increase in the occurrence of cerebral palsy, attributable mostly to the increased survival of very low birthweight infants.
There are several good articles that challenge the precautionary principle (e.g., Spiked and the Social Issues Research Centre). But, the relevance of the precautionary principle is not my primary concern. I am concerned that in raising the bogey-man of risk, there is no attempt to quantify that risk, nor to provide costings for the precautionary options.

Attack of the jelly babies, only one man can save usI do not mean to be flippant about environmental toxins or the exposure of pregnant women, foetuses and young children to chemicals that have a high index of suspicion. I and my siblings may well have been remarkably fortunate in having no obvious signs of in-utero or developmental harm despite our exposures. But, I do question the wisdom of releasing alarming information to parents when there is little chance that they can realistically avoid those toxins in their day to day lives. E.g., you may only buy washable clothes, but what if most other people in your office or on your plane are wearing clothes that have been to the dry-cleaners?

News seems to be a small part of journalism. Science coverage is notoriously poor and distorted: much of the information that we are given is meaningless and rarely quantified. However, whenever I read something that is calling me stupid for not recognising the current threat to my health, I remember how much the world has changed in 4 generations in my family. It is a random set of reflections and for the purposes of this piece, I shall overlook the depredations of both World Wars.

One of my grandmothers was the sole survivor from a house fire that killed 11 family members. All of my grandparents lost many family members, friends and neighbours during the Great Flu Epidemic. Other people that they knew were so weakened through malnutrition, disease and poverty, that they died later in the great smogs and fogs in the UK. My mother once lost 9 classmates (out of a class of 60) in one school term during an outbreak of diphtheria and Scarlet Fever. When I was 6, my best friend died: she had been a 'hole in the heart' baby. Throughout school, two more friends died with leukaemia. My older sister lost one of her friends and all of her family when they were in a plane crash. We knew of people in our church who died as a consequence of haemophilia. As an adult, most of the people from my generation who have died have been in a vehicle or sports accident. Generation 4 of my family doesn't know anybody from their generation who has died. Spiked sums it up rather well:
So far as scientific and technological advance goes, we are creating a safer world, rather than a more risky one. Just look at how much safer our children - the most vulnerable section of society - are today. At the turn of the twentieth century 150 in every 1000 babies born in England died before they reached their first birthday. Nutrition was poor and lack of vaccinations led to deaths from smallpox, diphtheria, measles, typhoid and cholera, and many other diseases. Most of these diseases are now virtually non-existent, mainly as a result of immunisation.

Furthermore, significant medical advances over the past decades have led to improved rates of survival for children diagnosed with cancer - such as leukaemia. Today infant mortality has dropped to fewer than five in every 1000 babies born.

Accidents in the home are also declining: open fires and unreliable gas heaters have been replaced by central heating; and candlelight has been replaced by electric lighting.
There is no room for complacency as most of these advances are limited to the developed world. But all of the advances that Spiked lists were grounded in the knowledge that those risks had quantifiable consequences. What are the risks of these toxins when compared to the risks to which my generation were exposed? Is it appropriate or even practical to avoid these risks or is it contributing to a system of organised paranoia? Like I said at the top, I think these concerns are out of proportion but then again, why would you listen to the opinion of someone with my in utero and early childhood exposure to environmental toxins?

For more information about the images used in the illustrations, click on them or visit the detail on Flickr for the Jellybabies. I strongly recommend looking at the rest of the Attack of the Jellybabies series. For more information about the mosaic images used in the illustration, click on it or visit the detail on Flickr.

Wednesday, November 08, 2006

The New Cough and Sneeze Etiquette

I have blogged frequently about the new cough and sneeze etiquette. There is now a fine educational video that will teach you how to execute this useful technique and cough/sneeze onto fabric instead. Watch and learn from Why Don't We Do It In Our Sleeves?

I recently accompanied an elderly neighbour to our local surgery for his flu shot. The waiting room was packed with elderly people getting their shots. A high number of them coughed-all of them covered their mouths with a hand. It might be useful if some waiting-rooms played this film, it might do a lot to reduce transmission.

Learn the new etiquette for coughs and sneezes. It's not what your mummy taught you. If you can't cover your mouth and nose with a tissue, use your upper sleeve whenever you cough or sneeze. Do not cover your mouth and nose with your bare hands. If you cough or sneeze into a tissue that covers your hands, then dispose of the tissue carefully and quickly, and then clean your hands (admire the thoroughness of the handwash technique in this video. It is important that you dispose of the tissue: do not shove the tissue back into your sleeve or a pocket.

It is time to trot out one of my favourite obscure words: fomites.
A fomite is any inanimate object or substance capable of absorbing, retaining, and transporting contagious or infectious organisms (from germs to parasites) from one individual to another.
If you sneeze or cough into your hands, or you handle a tissue into which you have sneezed, coughed or blown your nose, then you will contaminate other people or surfaces that you touch. The telephone in the video is an example of fomites.

I'm editing the above to include an item that HCW and others have sent to me. It seems as if people who are carriers for various bacteria such as Staphylococcus disperse the bacteria when they sneeze.
Nasal carriers of Staphylococcus aureus expel substantial amounts of the microbe when they sneeze, new research suggests. While the presence of the common cold does not affect this dispersion, respiratory allergies seem to increase it.
In fact, the researchers report that
having a respiratory allergy increased S. aureus spread during sneezing by 3.8-fold.
So, there are even more reasons to adopt the new coughs and sneezes etiquette.

Tuesday, November 07, 2006

Website for Young Smokers Who Want to Quit

A column of cigarette smoke passes from one open mouth to another: written under the smoke are the words 'Die with me'It is well-intentioned but there is a profoundly annoying yoof site for young smokers who want to quit. I don't know why these tremendously worthy bodies think that it adds to the credibility of a site if there are missing apostrophes and mis-spellings.

Another pet peeve is that the website does not conform to accessibility guidelines: I'm left to assume that the commissioners of the website do not perceive an urgent need to communicate the 'quit smoking' message to young people who might use screen-readers or other accessibility technology. It is unforgivable that they do not have alt tags or long descriptions available at crucial points. This really is a sore spot for me: I don't expect users to be aware of these issues, but it is beyond belief that public information websites (and even the larger commercial sites) are not accessible. E.g., on the crucial Why Stop? page, if you were to load that with a text browser (e.g., because of the bandwidth problems associated with browsing on a mobile phone or PDA) or need it read to you by a screen-reader (as some blind or vision-impaired people do, and as may be used by people with dyslexia) then there would be nothing on that page. All of the text is in the form of a graphics file, there is no text for screen-reading technology to read.

Liz Hughes, Youth Adviser for QUIT, is reported to say:
Knowing that there are over 4,000 chemicals in a cigarette, including arsenic which is also used in rat poison, is just one of many facts that help young people make an informed choice. We sought the views of hundreds of young people before creating this interactive site.
Did they really? Did they listen and not implement? Or did the young people claim that they respect sites that talk to them in the stilted language of 1950s public health films? Do young people refuse to read anything that isn't mis-punctuated and mis-spelt?

I don't understand who the target audience is for the facts section. Many of the facts are written in the passive voice (advocates for plain English complain vigorously about this structure and the complexity that it adds to the text). The facts are presented in very long sentences. The reading age for this material is high. However, in the UK, the average reading age of UK citizens is that of the average, educated 9 year old.

It is left up to Martin Dockrell of Asthma UK to make one of the strong public health messages:
You won't be surprised to hear that smoking with asthma reduces your lung function and worsens symptoms, but recent research has also shown that it interferes with the body's ability to absorb the most widely used preventer inhalers. To make things worse, otherwise healthy smokers are more likely to develop asthma.
We have one of the highest asthma rates among young people in the world, and yet that nugget of information is not highlighted on Quit Because. We have covered recent research that lends weight to the argument that people with asthma should quite smoking earlier this year.

Quit offers a confidential helpline on 0800 002 200 or email them for advice:

I hope that the website is successful in its mission. I can't think why it would be when it has so much disdain for potential users. So much care and attention was lavished on this site and its launch that even the official Quit newspage has made a mistake with the URL of the website. This website is of a piece with Wellchild's Children's Guide to Asthma. What a waste of scarce resources.

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

Sunday, November 05, 2006

Paediatric Grand Rounds 1:15 Is Up!

Book-front for Cherubs in the Land of LuciferPhillip V. Gordon, author of Cherubs in the Land of Lucifer, is the host of this week's Paediatric Grand Rounds 1:15 and it is an excellent read.

Autism is the special feature of the week and there are some fine video links in there that are thought-provoking viewing. There are several poignant, heart-breaking and infuriating posts about the the death of babies: there is guilt, and the sense of potential unfulfilled, of life denied and fury at political indifference.

There is a thoughtful crops of posts from parents of children with a range of conditions: some have tentative stories of improvement, others of a gradual decline. All of them are remarkable.

This PGR also has an invitation to all aspiring diagnosticians or House manque to contribute something to a diagnosis for Baby E.

Clark Bartram is always on the look out for new hosts for Paediatric Grand Rounds. You can consult both the hosting schedule and earlier editions in the Paediatric Grand Rounds archive.

PGR 1:15 is a fascinating collection of posts and Phillip Gordon is to be commended for it. The next host of this carnival is Tara Smith of Aetiology on November 19. Tara Smith is one of the very few people around who can make pathology, microbes and epidemiology fascinating.

Thursday, November 02, 2006

Record Spending on Baby Vitamins and Medicines in the UK

Calpol package for Infant SuspensionWhen in doubt, medicalise the problem and purchase a solution: increasingly, this seems to be the advertising message that can undermine parents' confidence in the way they treat their babies. The Telegraph carries a story about record spending on baby vitamins and medicines in the UK.

Vitamins? Is this expressing a lack of confidence in breast milk, infant formula or the quality of baby food that is being fed to babies? If the baby is feeding well, isn't it more likely that parents who give supplementary vitamins are in danger of over-dosing a baby? To quote the Paracelsus cliche, "the right dose differentiates a poison and a remedy". Vanessa Shaw is the head of Dietetics at Great Ormond Street Hospital and she is quoted as saying:
It would be interesting to tease out if parents are buying vitamins because they have been recommended to do so or if they have seen advertising or read about them and just decided to do it.
It would also be interest to know if the baby vitamin manufacturers are beginning to establish a successful market on the coat-tails of all the new stories about the supplementation of older children. Of course, if parents are going to use dietary supplements for infants, it is better that they should use an appropriate formula than attempt to halve or otherwise reduce tablets or drops intended for older children.

Reportedly, sales of painkillers and remedies for crying babies are increasing; more than 56% in a year. Parents bought more analgesics, which treat pain and high temperatures. Again, there has noticeably been more advertising about infant analgesia products over the last year. It is difficult to interpret this figure without knowing what has happened in the prescription market. If parents are confident enough to handle (say) a suspected acute otitis media or a cold by administering analgesia and watchful waiting before taking a baby to see the GP, then this increase could be A Good Thing because it is matched by a corresponding fall in prescriptions. I was a little disappointed by the suggestion that
mothers, particularly those who work, may have less tolerance for disturbed nights and a crying baby.
I do feel that this overlooks an economic reality for many families, and the fact that parents may be heeding the strong public health warnings that they should not drive when very tired. However, Prof. Choonara, a researcher in child health is quoted as saying,
[i]t is my impression that more parents are seeking medical advice over problems that are really about parenting. They ask questions that are really about normal development and that implies they are not getting support.
It is difficult to discern which of the many possible explanations is most plausible: it may be that different explanations are true of different demographics such as age-groups. However, one area in which there is consistently a triumph of hope over experience is the continued purchase and adminstration of colic medicines. Most parents know that the medicines are little better than a placebo but in the face of implacable crying, the are driven by the need to try to do something, anything, to soothe their colicky baby.

One of my recurrent issues is that some parents do not know how to reduce babies' breathing problems (that can interfere with proper feeding and can disturb their sleep). The following tips may be useful if your child has persistent episodes of breathing problems and in general:
  • Keep your child away from places where he/she is exposed to tobacco smoke.
  • Talk to your doctor or nurse about techniques for clearing the nose of babies (there is a wide assortment on the market from simple bulb aspirators to intimidating but widely-recommended gadgets that connect to a vacuum cleaner) and whether it is appropriate for your child. A few drops of saline into a baby's nostrils can help to clear the nose.
  • Learn the new cough etiquette. It's not what your mummy taught you. If you can't cover your mouth and nose with a tissue, use your upper sleeve whenever you cough or sneeze. Do not cover your mouth and nose with your hand. Dispose of the tissue carefully and quickly, and then clean your hands before handling your child.
  • Encourage children to breathe in and out through the nose wherever practical (even when asleep): there are substantial benefits.
  • Doctors are understandably reluctant to prescribe antibiotics for a virus: they are inappropriate in the absence of a secondary (bacterial) infection or other relevant medical history. Some doctors will cave in to pressure from parents but this is not necessarily in the interest of the baby's health. Follow your doctor's advice.
Of course, many parents know how to de-congest their baby but all too often, the resources of child-minders or pre-schools can not stretch to giving one-to-one assistance to a snuffly baby which will take longer than administering de-congestant drops.

Overall I am interested to know if parents are increasingly considering dietary supplementation for infants, following on from the news items about supplements for older children. How many consider them to be superfluous for babies who are feeding well, and how many think that they are a good idea, 'just in case'?

Wednesday, November 01, 2006

Borneo Breezes and Simpler Symptom Monitoring

Crowd of schoolchildren in South AfricaThere is a reasonable chance that I shall be going out to work in a clinic in South Africa for a while. If this happens, I shall be working in a township with an HIV infection rate of around 60% for adults. I shall be working with people with respiratory problems but mostly with children and adults who have asthma but do not have access to the drugs that are the gold standard of asthma management in the West. Similarly, I shall be working with children who have poor quality sleep with sleep-disordered breathing but have no likelihood of an ENT referral or adenotonsillectomy.

Understandably, any money that is available to the clinics in this, or similar townships, is spent on drugs to manage the HIV/Aids and opportunistic illnesses that are ravaging those communities. Nonetheless, asthma, allergies and SDB are growing problems in many countries on the continent of Africa, and they are interfering with children's attendance at school and some of their extra-curricular duties. The reasons behind the increase in these conditions is puzzling. Air quality is known to be very poor in many countries in Africa: this seems to be a combination of traffic pollution, emissions from heavy industries, and the particulates associated with cooking on open fires.

I'm excited and nervous about working in South Africa for a number of reasons. I know that I will need to modify some of what I teach to account for different learning styles. One of my aunts has been involved in setting up and running a school for blind children in Ethiopia so I know that story-telling, song and dramatisation are widely used in education. From Borneo Breezes, I learned about using puppets to act out some stories for public health.

Some of the exercises that I teach in the UK depend upon a timepiece - preferably a stopwatch to make it easier to measure seconds. I know that I wouldn't be able to rely upon this is many places in Africa so I was very grateful when Borneo Breezes very kindly passed on some of her experience and hints about how to monitor things like breathing rate.
We do an exercise you will find in our manual to teach moms how to distinguish "fast breathing" in young children so they can identify when to go to health units for treatment.

A stone is tied to the end of a piece of string and swung from shoulder height as a pendulum. The length of string is determined so the rate is that of an adult. The length is then shortened at a knot placed in advance so it is that of a well child. The string is then shortened again so that the back and forth of the pendulum as it is swung from the should approximates the rate of a child with "fast breathing".
This experiential technique allows mothers to be able to tell regular from "fast" breathing in much the same way medical students through repeated observation, learn to identify it without a watch.
This is exactly the sort of 'low-tech' tip that I need to know. So, if anybody else has similar tips, please don't be shy, I would be so pleased to hear about them.

I already know that I will have to rethink those parts of the workshops that rely upon using Darth Vader as an example of noisy breathing, or that rely upon working with bubble mix to demonstrate breath size. Unless, of course, somebody knows a very robust bubble mixture that I'm likely to be able to make up with local materials? I've been talking with a couple of science teachers and they reckon that if I bring out some coat-hangers and some wire snippers with me, then I should be able to make bubble frames. I have no idea how I'm going to replace the soda volcano experiment that I use to show how you can mix substances together to release energy.

Similarly, I need to re-think a lot of the stories that I tell to the children. They tend to be variations on nursery rhymes and children's songs and well known children's characters.

I'm excited at the thought of going. I just need to give the matter of how to teach the material in an appropriate way some more thought.

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