HYPERSENSITIVITY TO COCKROACH IN CHILDREN WITH ASTHMA

Cockroaches are major house dust allergens whose role in pediatric all ergies is well documented. Three cockroach species are known to cause allergies in humans, namely Blatella germanica, Periplaneta americana, and Blatta orientalis. The prevalence of a positive prick test to Bla tella germanica was determined prospectively in 100 pediatric patients newly diagnosed with asthma. The 42 patients with a positive test, 32 boys and 10 girls, had a mean age of 6.04+/-3.52 years with a range o f 2-12 years. Most (34/42, 80.9%) lived in old, dilapidated overcrowde d dwellings, and all were exposed to cockroaches either at home (41/42 ) or at school (1/42). Eighteen of the 42 cockroach-sensitive children (42.85%) had mild asthma, 13 (30.95%) had moderately severe asthma, a nd 11 (26.20%) had severe asthma. Thirteen children (13/42, 30.95%) ha d no other allergic diseases, whereas 24 (57.14%) had rhinitis, 13 (30 .95%) had conjunctivitis, and nine (21.43%) had atopic dermatitis. Two children (3.45%) had a history of urticaria and one of recurrent lary ngitis. The total serum ISE level was greater than 500 IU/ml in 31 chi ldren (74%). Cockroach allergen was the fourth most commonly positive skin test, after D pter (89%), PDM (87%), and D far (72%). Many patien ts with a positive skin test to cockroach allergen also had positive t ests for house dust mites (95% for D pter, 92.6% for PDM, and 70.7% fo r D far). In only one patient was cockroach allergen the only positive skin test. The high prevalence of hypersensitivity to cockroaches war rants that cockroaches be added to the list of allergens included rout inely in prick-test evaluations of asthma patients.