Sensitization to three house dust mites (Dermatophagoides pteronyssinus, Dermatophagoides farinae, Blomia tropicalis) in asthmatic and rhinitic patients living in the Maghreb and sub-Saharan Africa

Purpose. - To determine sensitization to three house dust mites in allergic patients living in the Maghreb and sub-Saharan Africa. Methods. - This was a prospective study which included 1401 allergic patients ranging from 3 to 65 years of age in whom sensitization to three house dust mites (Dermatophagoides pteronyssinus [Dpt], Dennatophagoides farina [Df], Blomia tropicalis [Bt]) wag determined by prick skin testing. Results. - Six-hundred and thirty-eight men (46%) and 763 women (54%) were included; their average age was 26.3 +/- 16.2 years. All patients had clinically significant allergic symptoms; the most frequent symptoms were nasal itching, runny nose, sneezing, coughing and wheezing. The overall prevalence of skin sensitization to these mites was 72%: 89% were sensitive to Dpt, 81% to Df and 54% to Bt. Monosensitization to Dpt, Df, and Bt was noted in 10.2%, 3% and 4.3% of the cases respectively. Sensitization to mites was highest in women and it decreased with age (P <0.05). It was correlated with rhinitis and conjunctivitis but not with asthma (P < 0.05). In patients with mite sensitization, the most common triggers were exposure to dust, to moisture and to cold (P < 0.05). We found that the prevalence of sensitization to Bt varied between different countries. Conclusion. - Sensitization to house dust mites is frequent in the Maghreb and sub-Saharan Africa and its prevalence varies between countries. Sensitization to Bt is not rare in this part of Africa, with its prevalence being highest in Morocco and Senegal. (C) 2014 Elsevier Masson SAS. All rights reserved.