Asthma in the desert: spectrum of the sensitizing aeroallergens

Background: Bronchial asthma is common in Kuwait, a desert country, but the sensitizing allergens are uncertain. This study investigated the sensitizi ng allergens in Kuwaiti patients with extrinsic asthma. Methods: A total of 553 asthmatics (male:female ratio: 1.4; mean age: 31.7 years [range 3-76 years]) and 112 matched controls were studied. Sera from all patients/subjects were tested by the CAP-RAST method for specific IgE t o 14 locally relevant inhalant allergens. Results: Specific IgE to at least one allergen was detected in 87.2% of the patients compared with 24.1% of controls. Among the confirmed extrinsic as thmatics, the sensitization rates for the allergen groups were as follows: pollens (87.1%), house dust (76.1%), and molds (30.3%). The three most prev alent sensitizing pollens were from Chenopodium (70.7%), Bermuda grass (62. 9%), and Prosopis (62.7%), all of which are horticultural plants imported f or the purpose of "greening" the desert. For all allergens, except the mold s, the prevalence rate was higher in males than females, but age had only a weak effect. Severe asthma occurred significantly more frequently among mo ld-sensitized patients. Conclusions: These results show that even in a desert environment, pollens and house-dust allergens may be important sensitizing allergens. They also illustrate how practices that "green" the desert can affect public health.