Clinical and anamnestic characteristics and results of allergological testing in children with bronchial asthma and allergic rhinitis in case of allergy to house dust mites

Abstract

House dust mites (HDM) are a common cause of allergies, however, it is not always easy to suspect a mite allergy from a patient's history. 
 Objective: to determine clinical characteristics of patients, tactics for demonstrating the role of HDM sensitization in pediatric patients with allergic rhinitis (AR) and bronchial asthma (BA) with domestic sensitization. 
 Materials and methods. The study included 420 patients, 256 boys, 164 girls, aged 5 to 17,9 years (mean 8,44 ± 3,06 years), with AR (100%) and AR in combination with BA (41,9%). The prick test on the forearm skin with water-soluble extracts was carried out and evaluated according to the standard method. The test was considered positive with a maximum wheal diameter of ≥3 mm 15 minutes after applying the prick. 
 Results. Among patients with HDM sensitization (n=268), sensitization to both mites was detected in 218 cases (81,3%), and in 139 cases (51,9%) polysensitization to HDM allergens, house dust and epidermal allergens (cat, dog) was found. Patients noted persistent symptoms of nasal congestion, and rhinorrhea; the provoking factor was not determined by history in 46% of cases. In 69,8% of cases (97 children), it was impossible to isolate the leading allergen according to the history, since patients had contact with cats, dogs, dust, and polysensitization according to the prick tests. Nasal provocation test (NPT) with HDM allergens was performed in 92 children. Positive NPT was obtained in 83 cases (90,2%), negative in 9 cases (9,8%). 
 Conclusions. With HDM sensitization, often (46%) the provoking factor is not determined by history. Monotonous symptoms are characteristic with the absence of obvious relationships with allergens, the location and activities of the child. In terms of frequency, the leading variant is sensitization to both mites D.pteronyssinus, D.farinae (81,3%), and polysensitization to HDM, house dust and cat and dog allergens (51,9%). NPT allows in 90% of cases to show the causal role of HDM allergens in polysensitized patients with insufficiently convincing anamnesis data.