PREVALENCE OF ALLERGIC SENSITIZATION TO INHALANT ALLERGENS AMONG BLOOD-DONORS IN KUWAIT - A DESERT COUNTRY

Kuwait is a desert country where the prevailing high temperatures, low humidity, and scant vegetation suggest a low prevalence of allergy, W e evaluated the prevalence of atopic sensitization (presence of allerg en-specific IgE) among young adult blood donors by screening a total o f 505 subjects (male : female ratio 1.6) with mean age of 28.4 years ( range 18-50 years). The Pharmacia CAP-Phadiatop(R) test, which detects serum IgE specific to most common airborne allergens, was used. Some of the specific sensitizing allergens were also identified by the rela ted CAP-RAST method, Sensitization tvas detected in 223 of the 505 sub jects (44.2%) screened, Kuwaiti nationals had a significantly higher p revalence rate (50.2%) than non-Kuwaitis (34.2%) (chi(2)=8.6, P<0.003) . The highest prevalence rate was found among male Kuwaitis (53.8%). T he prevalence of current or previous allergic disease (subject-reporte d) was 20.6%. Bermuda grass, house-dust mite (Dermatophagoides pterony ssinus), and Chenopodium album were the most prevalent sensitizing all ergens, with frequencies of 53.6%, 52.7%, and 50.9%, respectively, amo ng the sensitized subjects (corresponding to 23.7%, 23.3%, and 22.5%, respectively) for the entire population. Sensitization increased with age, but only among the expatriates, younger Kuwaitis being as frequen tly sensitized as the older ones, Polysensitization was found to be co mmon, Of the 109 CAP-RAST-positive subjects, 71 (65.1%) were sensitize d to more than one allergen, and 30 of these (42.3%) were sensitized t o four or more allergens. These results show that atopy is highly prev alent among young adults in Kuwait, and the higher prevalence rate amo ng nationals than expatriates suggests the involvement of genetic or l ocal environmental factors. The results also confirm that mite and pla nt pollens may be major sensitizing allergens even in a desert environ ment.