Category Archives: General paediatrics

Prevention of peanut allergy

Allergy, General paediatrics, Immunology,

Use of peanut oil in eczema creams had OR 8 for peanut allergy but retrospective.

Filaggrin deficiency has OR 5 for food allergy, only 3 for eczema!

So could skin protection (particularly in babies with eczema) before early weaning prevent food allergy? Preliminary studies suggest 35- 50% response. Evidence that peanut consumption of household predicts peanut allergy in baby – presumably by skin sensitization.

Bamba peanut snack

Jewish children in the UK have a prevalence of peanut allergy that is 10-fold higher than that of Jewish children in Israel. This difference is not accounted for by differences in atopy, social class, genetic background, or peanut allergenicity. Israeli infants consume peanut in high quantities in the first year of life, Bamba (peanut snack, like a Wotsit) often used for weaning, so most infants have been exposed by age 12 months. [Du Toit  J Allergy Clin Immunol. 2008 Nov;122(5):984-9]

Gideon Lack at Evangelina hospital in London did LEAP study (Learning about Peanut Allergy), randomized infants with severe eczema and/or egg allergy to receive either no peanut until age 3yr, else an age-appropriate peanut snack (Bamba or smooth peanut butter, 6g) three times a week.   Among the 530 infants in the intention-to-treat population who initially had negative results on the skin-prick test, the prevalence of peanut allergy at 60 months of age was 13.7% in the avoidance group and 1.9% in the consumption group (86% reduction, P<0.001). 98 participants had baseline positive SPT results, only 12% had a positive challenge so most continued the protocol.  Another 10% with SPT>4mm were excluded from the start.

Adherence to the diet was excellent.  Dust samples were taken from some participants’ beds, peanut levels were significantly higher for kids in consumption group.  There was a higher rate of urticaria in the consumption group.

IgE greater than 10 in peanut avoiding group had 100% PPV for allergy.  Peanut-specific IgG4 antibody seems to be linked to tolerance – it went up more in the consumption group, and IgG4:IgE ratio was generally lower in allergic group (most had IgG4 under 1000). [NEJM 2015; DOI: 10.1056/NEJMoa1414850]  See also LEAP-On study, which is the follow up at 72 months, still significant difference.

Michael Perkins’ EAT study of early introduction of 6 common allergens in non-high risk babies showed if strict adherence to protocol eg 2g weekly of peanut, then every case of peanut allergy could be prevented.

Risk of peanut allergy in high risk babies estimated to be about 14%. Cost benefit analysis suggests better to go for early introduction WITHOUT initial testing, as high rate of false positives. Yet in the US at least, lots of early screening happening (median number of foods tested =10!), rarely followed by oral challenge. If you tested every high risk baby in the US with IgE, it would cost $900m…

 

 

 

Influenza – treatment

General paediatrics, Infectious disease, Respiratory

Oseltamivir and Zanamivir licensed for treatment and the former also for post-exposure prophylaxis.

Cochrane review 2014 found little evidence of benefit.  But this was based on community studies in healthy populations.

“Use of neuraminidase inhibitors in influenza” [October 2015, Academy of Medical Sciences] indicates that the use of antivirals can be beneficial in certain situations, but of limited use in others. Additionally, a recent review “Expert opinion on neuraminidase inhibitors for the prevention and treatment of influenza – review of recent systematic reviews and meta-analyses” August 2017, European Centre for Disease] supports use as treatment and prophylaxis.

UKHSA therefore recommends:

“Complicated” influenza defined as

  • requiring hospital admission,
  • signs of LRTI eg resp distress, chest signs
  • CNS signs
  • Worsening of underlying medical condition

Risk factors include:

  • infants under 6 months; 
  • neurological, hepatic, renal, pulmonary and chronic cardiac disease ; diabetes mellitus;
  • severe immunosuppression (includes prednisolone r≥2mg/kg/day for ≥1 week);
  • morbid obesity (Z score BMI 3.33 or higher).

Oseltamivir (Tamiflu) PO or NG is first line, unless severe immunosuppression and A(H1N1) variant prone to resistance dominant – then zanamavir.

  • Start treatment within 48hrs, do not wait on lab confirmation of diagnosis.  May still be benefit in life threatening illness when started up to 5 days after onset. Rule is within 36hrs if child and zanamavir.
  • should NOT be used in otherwise healthy patients but can be considered if felt to be “at serious risk of developing complications”.
  • Test for resistance if no response after 5 days of treatment.

Presumes flu-like illness and circulating influenza, CMO publishes advice when surveillance levels cross threshold.  Highly virulent strain would change things, of course. Further details including use of anti-virals at HPS.

Oseltamavir dose is twice daily for 5 days. Oral only, capsules can be opened and added to something sugary (very bitter).  Liquid preparation available but limited supply, prioritise for infants.  Give by NG if necessary.  Licensed for treatment at all ages now, prophylaxis only over 1 yr.  Diarrhoea and vomiting are the only significant side effects.  

The earlier it is started the better: starting within 12 hours reduced duration of illness by 3 days, start within 48 hours and only 1 day benefit. 5% of childhood infections will become resistant whereas this is unusual in adults, probably due to kids having higher viral loads in primary infection. Consider resistance if no benefit after 5 days treatment.

Zanamivir used for adolescents 12 years and older – taken again twice daily for 5 days by diskhaler (age less important than ability to use device!). No resistance, very low rate of side effects (wheeze!). Zanamavir is preferred in severely immunocompromised AND (probable) A(H1N1)pdm09 disease, as resistance is higher . Unlicensed IV form of zanamavir is available on compassionate named patient basis.

[Antiviral PHE guidance]

Prophylaxis

For prophylaxis, vaccination best!  But consider using anti-virals (NICE recommendations) for post-exposure prophylaxis with Oseltamivir where:

  • 13yrs or older
  • Have a risk factor, as above
  • Influenza A or B is circulating, as above
  • Present within 48hrs of close contact exposure
  • Have not had flu vaccine for this season, or too recently for it to have been effective (within 14 days), or the wrong type, or have a condition that means vaccine may not be fully effective, or localised outbreak eg care home

Dose is once daily for 10 days. Treatment for up to 6 weeks might be required during an epidemic.

Other comments

Amantadine not recommended – targets M2 protein, only effective against type A influenza, rapid resistance and side effects common.

2 adolescents in Japan have committed suicide while on oseltamavir, plus there have been a number of other neuropsychiatric reports.

Peramivir is IV preparation with marketing authorization in EU, not yet available in UK.

Wheeze

Common, General paediatrics, Respiratory

US and elsewhere use “bronchiolitis” to mean wheezing illness!  So beware definitions in studies.

Early aeroallergen sensitization predictive of ongoing symptoms and loss of lung function at school age, but does not predict response to treatment with inhaled corticosteroids (ICS)!

European Resp society task force diferentiate Episodic Viral Wheeze (EVW) from Multiple trigger wheeze (MTW) viz exercise, smoke, allergens.  Children may change categories over time.  Guides treatment.  But note that few RCTs have used this classification, and tend to conflate.

MTW is associated with more airflow obstruction, and the pathology (eosiniphilic inlfammation and remodelling) similar to asthma.  Eosiniophilic inflammation not seen in EVW.

Several clinical indices which attempt to predict future asthma – PPV generally under 50%.  Kids with EVW only have no increased risk of respiratory symptoms once they reach age 14.

No evidence that early ICS (intermittent or continuous) affects progression of disease.  [N Engl J Med 2006;354:1985-97 PMID 16687711]

Parental smoking linked to wheeze, asthma, bronchitis and nocturnal cough, with mean odds ratios all around 1.15, with independent effects of prenatal and postnatal exposures for most associations (PATY study (Pollution And The Young), n=53 879 children from 12 cross‐sectional studies).   “Not in front of the children” does not protect from effects [Jenny Pool, Cambridge – Thorax 2012;67:926]: 88% of children from families where parents only smoke outside still have detectable urine cotinine.  Nicotine levels in household dust and on surfaces is at least 3x higher in homes where parents smoke indoors, but still 5-7x higher in homes where parents smoke outside cf non-smoking houses [Tob Control 2004;13:29-37 doi:10.1136/tc.2003.003889].  Air pollution increases vulnerability to preschool wheeze, but no specific advice on individual exposure.

PREEMPT study of intermittent montelukast (1 week with onset of URTI) for EVW vs placebo reduced unscheduled consultations for asthma, days away from sc hool/nursery, parental time off work.  [Australia, Am J Respir Crit Care Med. 2007 Feb 15;175(4):323-9.] Similar findings from a US study, but not supported by much larger WAIT study, 3 way study of intermittent vs continuous montelukast vs placebo [Nwokoro, Lancet Respir Med. 2014 Oct;2(10):796-803. doi: 10.1016/S2213-2600(14)70186-9].  But “5/5 ALOX5 promoter genotype might identify a montelukast-responsive subgroup”? Discontinue when child is better, not after specified number of days!

Cochrane supports intermittent ICS for wheeze, but only due to small studies with unlicensed doses eg fluctic 750mcg BD!  No studies of combined ICS/montelukast.

No evidence for prophylactic continuous ICS, but studies looked at mild rather than severely affected children.   Could be tried if repeated hospital admission, in case interval symptoms underappreciated!  Beware growth suppression, review and wean/stop if able.

Hospital study of pred vs placebo (n=687) found no benefit!  SImilar study in primary care.  SO should not be automatic, esp when anticipated duration of admission less than 24 hours.

No evidence for treatment plans for preschool wheezers!

BMJ 2014;348:g15 Andrew Bush

Advisory labels

Allergy, General paediatrics, Immunology

Or precautionary allergy labelling.

What are Precautionary allergy labels?

These are extra bits of information sometimes provided on labels, in addition to the actual ingredients.  Phrases like “May contain…”, “Made in a factory where…”.  These precautionary allergy labels are not legally required, but manufacturers are encouraged to use them to warn their customers of a risk of accidental contamination during the production process.  The Food Standards Agency  (FSA) (2006) encourages manufacturers to be as precise as possible eg which specific nut, or else peanut or “tree nuts” rather than just “nuts” but in reality different companies do different things eg Kelloggs does not differentiate between peanut and tree nuts when they put a warning label on about nuts.

Is there a real risk or not?

Contamination of chocolate is a particular problem, particularly with nuts, and with milk in the case of dark chocolate.  In some studies, half of all the chocolate tested was contaminated.

But most foods carrying such a label will not contain any of the allergen mentioned, indeed it is sometimes hard to imagine how it possibly could!  In an Irish study looking at foods labelled marked “may contain peanut/nut”, 5% had detectable peanut or nut, which is a significant proportion but actually the peanut or nut was present at such low levels they would be unlikely to cause a reaction in the majority of allergic people.

Aren’t they just a way of avoiding legal liability?

The FSA clearly state that these labels should only be used where there is a real and unavoidable risk.  And in any case, it’s not clear it changes the company’s legal responsibilities – if there is evidence that a manufacturer has been producing food in an unsafe manner, they would be liable regardless of whether there was a warning or not.

When is a trace not a trace?

The idea of threshold is important – how much of the allergen is actually present, and is it even enough to cause a reaction?  Not everyone reacts at the same threshold, and the differences between individuals can be a factor of ten or even a hundred.

In big study of peanut challenges in kids, those who got through to last stage were 13x more likely to have anaphylaxis (related to total amount of peanut consumed, presumably). Higher thresholds found in older kids, perhaps because they would have presented earlier if they had lower threshold? [PAI 2018 vol 29:754-761]

Australia and New Zealand ask manufacturers to look at actual levels of contamination before putting a warning on their products.

In the UK and Europe, the risk associated with the processes is what matters, rather than the actual levels of contamination. It’s not clear which is actually more useful.

So what should you do about traces?

Many people tend to ignore these warnings, particularly when it is something they have eaten many times before, or when it is a big brand name, and when the wording is ambiguous rather than direct.  Yet there is no good evidence that any of these things actually makes a difference to the real risk.

What is definitely true is that people have unexpected reactions and this can be after eating things marked with these warnings, but equally after eating things without these warnings.

What is also true is that allowing yourself to eat things marked with these warnings makes life much simpler!

Some patient organizations eg Anaphylaxis Campaign recommend avoiding anything marked with precautionary allergy labels, if only because this puts the control in your hands rather than leaving you at the mercy of the manufacturers.

Doctors often recommend avoiding anything with an allergy warning, because it “seems” safer and they don’t appreciate how difficult it is in day to day life.

So I think you have to make your own choice.  If you have a nut allergy, and it’s chocolate or something else that often does contain nuts eg a muesli bar, then to me the risk seems too much.  It it’s something that wouldn’t usually contain nuts, and you’ve had it before, and you’re at home with your family, then maybe the risk is acceptable to you.  But if you are away on holiday, and you’ve forgotten to bring your allergy medicines, and your asthma is playing up, and it’s late at night, then that’s probably the worst time to take a chance.    

[https://www.food.gov.uk/business-guidance/allergen-labelling-guidance-for-food-manufacturers]

Plantar warts

Common, Dermatology, General paediatrics

2/3 resolve within 2 years.  In young children, higher spontaneous clearance.  In systematic review, only salicylic acid and aggressive cryotherapy seem to be effective.  Both are user dependent.  In RCT between the 2 and conservative management, no difference detectable after 13 weeks.  So watch and wait, unless causing a lot of pain.

Perianal warts can be transmitted vertically from mother at birth, or potentially from carers changing nappies.

Warticon cream is podophyllotoxin. Else Condyline paint.

Risk factors of allergy

Allergy, General paediatrics, Immunology

Children reported to have taken antibiotics during infancy (0-2yrs) were more likely to have asthma at 7.5yrs, with a dose response pattern.  No association between antibiotic use and atop on skin prick testing however!  Hoskin-Parr, Ped All Imm 2013;24:762 (Avon longitudinal study)

 

At 18/12 of age, babies born by SVD and whose parents suck their dummy are 2.5x less likely to have eczema than those born by LSCS whose parents do not suck their dummies.  Germany/Sweden, Peds 2013;131:e1829

 

Children born outside of US much less likely to have allergic disorder (OR 0.48), although those who have lived in US for 10+yrs have higher odds of eczema and hay fever cf those who have lived in US under 2 years.  But not clear whether children moved from developing or developed country.  Ped 2013;167:554

 

Inverse dose response effect between food diversity in infancy and asthma (OR 0.74).  26% reduction in asthma for every additional item of food added in the first year of life.  Increased risk of food allergy by age 6yr (OR0.7), but no longer statistically significant after excluding children with food allergy in the first year of life.  European cohort, JACI 2014;133:1056

Prognosis of type 1 diabetes

Endocrinology, General paediatrics,

Life expectancy now into 70s.  Rates of diabetic nephropathy have fallen over the last few decades, and progression is dramatically reduced thanks to prevention and treatment strategies.  Cancer and not CVS disease is now the main cause of death!  Survival seems to be as much about dealing with obesity, insulin resistance, hypertension and arterial disease – as you would for type 2.

Food allergy labelling

Allergy, General paediatrics, ,

The UK still currently follows the European Food Information For Consumers Regulation (FIR) that took effect from December 2014.

This applies to unpackaged food eg restaurants, takeaway’s deli’s, bakeries etc. It now also applies to food prepacked for direct sale (PPDS) such as a sandwich made on the premises of a cafe but wrapped (Natasha’s law).

Allergy advice boxes are no longer permitted, although “may contain” advisory labels are. The allergen should be emphasised in the ingredients panel through typeset eg font, style, colour.   The specific type of cereal or nut must also be stated.

The 14 allergens that must be highlighted under UK/European law are: cereals containing gluten (wheat, barley, rye etc), crustaceans (eg shrimp, prawn), molluscs (eg mussel, oyster), eggs, fish, peanuts, nuts, soybeans, milk, celery, mustard, sesame, lupin and sulphur dioxide at levels above 10mg/kg, or 10 mg/litre, expressed as SO2. Lupin and Molluscs added later.

There are some exceptions, where the food is so highly processed that they are no longer capable of triggering an adverse reaction eg fish gelatine in beer/wine, soya in vegetable oil.

If your allergy is not one of those listed, eg lentil, there is no legal duty for the manufacturer to highlight the presence of that ingredient, or for the restaurant to provide a full list of ingredients.  So you need to read the full list of ingredients carefully, and plead with the restaurant for details relevant to your allergy. In the past, some manufacturers highlighted allergens in a separate box, but this is no longer permitted.

The rules list nuts as:

  • almond,
  • hazelnut,
  • walnut,
  • cashew nut,
  • pecan nut,
  • Brazil nut,
  • pistachio nut,
  • macadamia nut or Queensland nut
  • and products made from these nuts.

Other types of nuts, and other foods which are not nuts (even though they are called nuts i.e. chestnuts, pine nuts and coconut), are not named in the rules, even though they are known to cause allergy in some people.

Note that by law, “cereals containing gluten” includes oats! Spelt and Kamut should be declared as containing wheat. Oats contain avenin, rather than gliadin, but related. Products containing oats that have not been contaminated by wheat can be declared “gluten free” by law, so effectively the law considers oats as both containing but not containing gluten…

See also Advisory labels.

(food.gov technical guidance on new labelling law)

There is no legal duty to highlight changes in recipes on packaging.  The same product with the same packaging can sometimes have different ingredients, depending on where it is produced.

The Food Standards Agency (FSA) has ordered councils to encourage restaurant owners to check their ingredients.

Note that non-EU countries will have their own rules eg US has only 10 ingredients that must be highlighted (not molluscs, mustard, celery, or lupin).

Lymphadenopathy

Clinical, Common, General paediatrics, Haem/Oncology, Infectious disease

A good proportion of healthy children will have palpable lymph nodes in the neck.  Mostly these will be under 1cm in diameter.  Acute enlargement as part of an upper respiratory tract infection is usually accompanied by tenderness, and affected nodes will reduce in size over 4-6 weeks.

Guidance from NICE and the Scottish Government provide criteria when children with lymphadenopathy should be urgently referred for suspected cancer.

These criteria include the following:

  • lymph nodes are non-tender and firm/hard
  • lymph nodes are greater than 2 cm in size
  • lymph nodes are progressively enlarging
  • other features of general ill-health, fever or weight loss
  • the axillary nodes are involved (in the absence of local infection or dermatitis)
  • the supraclavicular nodes are involved.

But caveat is “Always refer any patient with Repeat presentations (3 or more times) of any physical symptoms which do not appear to be resolving or following a normal pattern, taking into account parental and patient concern”.

No need to do bloods in the absence of any of these criteria. Not that cancer is the only concern – differential includes developmental lesions (branchial cysts etc), TB, Cat-scratch disease, non-tuberculous mycobacterial infection (esp in neck).  These are always more than 2cm and there may also be systemic features and/or overlying skin discolouration too.

Malignancies often present in the head/neck region.  Hodgkins lymphoma usually affects teenagers, Non-hodgkins tends to affect school age children, neuroblastoma tends to affect pre-school children.  B-symptoms (recurrent fever, weight loss, night sweats, pruritus, lethargy) are only seen in a minority but does suggest more advanced disease, of course.  Airway or voice changes, swallowing difficulty, Horner’s syndrome, superior vena cava syndrome may all be seen due to mass effect. Most neuroblastomas have an abdominal mass.  Nasopharyngeal carcinomas are seen so look in the nose/throat.