Dr. Adrian Morris of Surrey Allergy Clinic Tests and Treats allergies

Outgrowing egg allergy

Dr. Adrian Morris — Mon, 26 Jul 2010 11:26:33 +0000

Hen egg allergy is very common in infants with eczema and usually outgrown by age 6 with a few children retaining their egg allergy into adulthood. The egg white or albumin is more allergenic than the yolk and heat or cooking damages the allergen making it less allergenic. Some children will therefore tolerate cooked but not raw egg, whereas other more severely allergic children will react to all traces of egg. Early onset of egg allergy is associated with asthma at age 18 months. Fortunately the Measles (MMR) vaccine no longer contains any egg so is not contraindicated in egg allergic children. However the Influenza and Yellow Fever vaccines are grown on chick egg embryo’s and therefore may be a problem for egg allergic children.

A new ImmunoCAP f233 blood test can now determine whether hen’s egg allergy is likely to be severe and persists into adulthood. Once the IgE skin prick test or blood RAST testing show a positive allergy result for eggs, a further test for raised antibodies to the heat-stable egg protein Ovomucoid (Gal d 1) is very useful for determining if egg allergy will persist.

Ref: Ando H, Moverare R, Kondo Y et al Utility of ovomucoid-specific IgE concentrations in predicting symptomatic egg allergy. J Allergy and Clin Immunology 2008:122;583-8.

Peanut allergy manifests in different ways

Dr. Adrian Morris — Fri, 16 Jul 2010 07:43:11 +0000

Not all peanut allergy sufferes react in the same manner. Some will only have mild oral itching after eating a handful of peanuts, while others will have catastrophic anaphylaxis after minor exposure to airborne peanut allergen. Some peanut allergy sufferers will also have reactions to other seeds such as Sesame or tree nuts such as Brazil nut, Hazelnut and Walnut. While others may only react to legumes such as beans, peas and lentils. Yet others may have allergic cross-reactions to soybean and lupin flour.

This has all been rather unpredictable and guess work until recently when a new blood tests was developed which can show with accuracy which part of the peanut an allergy suffer has or will react to in the future. For example there is a particular peanut protein called Ara h 2 which is likely to cause anaphylactic reactions. This type of component allergy test is useful in predicting whether a cross-reaction to nuts, beans, seeds or fruit is likely to occur.

Peanut component allergy testing and likely cross-reactivity:

Ara h 2 High risk anaphylaxis to peanut and nuts

Ara h 1 – cross-reactions with legume (pea, bean, lentil) and nuts

Ara h 3 – cross-reactions with soybean and lupin flour

Ara h 8 – localised oral reactions to peanut and stone-fruit only.

Reference: Astler C et al. Journal Allergy and Clinical immunology 2007: 118; 250

Mildew allergy in severe asthma and sinusitis

Dr. Adrian Morris — Tue, 01 Jun 2010 17:51:55 +0000

Mould or fungal spores contained in black mildew which grows both indoors in damp bathrooms, kitchens and cellars and outdoors on dead leaves particularly in autumn can trigger severe asthma and chronic rhino-sinusitis. The main fungal culprits namely Cladosporium and Aspergillus can trigger brittle and difficult to treat asthma as well as chronic sinusitis in allergy prone individuals. This mould allergic asthma may occur as change-of-season epidemics and result in severe asthma attacks often necessitating hospitalisation and ICU admission.

Moulds and fungal spores are also recognised causes of a number of respiratory problems especially in immune-compromised leukaemic and transplant patients, elderly with chronic bronchitis, children with cystic fibrosis and those suffering with HIV and TB. In northern Europe a delayed hypersensitivity to the Aspergillus mould may result in Acute Bronchopulmonary Aspergillosis (ABPA) which causes progressive lung damage with cavities (bronchiectasis) and severe disability.

In addition to Aspergillus and Cladosporium other allergy trigger factors in difficult to treat asthma may be common environmental fungal spores such as Alternaria, Penicillium (mouldy fruit), Botrytis (blight) and even common skin fungi such as Candida (thrush) and Trichophyton (ringworm) mould spores. This condition is called SAFS or Severe Asthma with Fungal Sensitivity which is ordinarily very difficult to treat with resultant severe asthma exacerbations despite high doses of inhaled preventer and reliever medication. Recent research has highlighted the probability that up to 60% of these patients may respond well to antifungal medication such as itraconazole and amphotericin B.

Reference: Denning DW, Driscoll B R, Hogaboam CM , Bowyer P Niven RM, The link between fungi and severe asthma; a summary of the evidence. European Respiratory Journal 2006; 27:615-626

Allergy to Henna tattoos

Dr. Adrian Morris — Sun, 02 May 2010 15:18:36 +0000

Summer is here, it’s time for a sunny break abroad and perhaps a temporary tattoo which is very fashionable. But beware, temporary Henna tattoos done on unsuspecting holiday makers in tourist resorts can have a disfiguring long-term and even dangerous result. The usually harmless Henna-plant tattoo chemicals are often illegally darkened by unscrupulous vendors adding a concentrated hair dye chemical called PPD (para phenylene diamine) or “Black Henna”. This dangerously concentrated hair dye chemical is highly sensitising when applied neat onto the skin and in 15% of people will lead to a delayed allergic reaction some days later (usually after returning home from their holiday). Tell-tale allergy signs include irritation and reddening of the tattooed skin, later resulting in a blistering and scarring contact dermatitis which in some cases can last many weeks. The long-term consequences are that once sensitised to PPD, you will have a life-long risk of reacting to other less concentrated-PPD containing hair colourings, black rubber products, sulphonamide antibiotics, local anaesthetics and even sunscreens containing PABA (para-aminobenzoic acid). Therefore be extremely cautious about having any temporary Henna tattoos applied to your skin whilst on holiday.

Reference http://en.wikipedia.org/wiki/Henna

Volcanic ash cloud and allergy

Dr. Adrian Morris — Fri, 16 Apr 2010 14:46:34 +0000

The Volcanic dust and ash cloud currently drifting over western Europe from Iceland is unlikely to cause any acute health risk or exacerbate allergies and asthma in the United Kingdom. Volcanic ash contains fine grains that may irritate the airways, as well as associated sulphur gas, but the amount that falls to earth and reaches ambient air is likely to be very small. Scientists believe it will be equivalent to Sahara desert sand particles that are regularly drawn up into the atmosphere and then sprinkled down over Britain. Allergy and allergic asthma sufferers should continue to use their preventer and reliever inhalers as usual and see their GP if they have any health concerns.

Reference: Skynews.com