The relationship between house dust mites and environmental factors beyond the analysis power of a skin prick test

Introduction
The house dust mite is a major cause of allergic disease. The standard diagnostic techniques consist of determination of the immunoglobulin E (IgE) level in blood and the application of a skin prick test. The skin prick test results are not always reliable because only 2 common species are determined by the test. Thus, the prevalence of mite allergy in a population requires microscopic analysis of collected samples.

Aim
This cross-sectional study was conducted to investigate whether skin prick test results are compatible or not with the presence of mites in a house.

Material and methods
A total of 84 allergic patients were included in the study. A questionnaire was applied to detect allergic risk factors. The skin prick test was performed to ascertain if the allergy occurs due to Dermatophagoides pteronyssinus and D. farinae. Patients were requested to take dust samples from their homes to determine the sensitivity of the prick test.

Results
In our study, we have shown that D. pteronyssinus and D. Farinae are the common (32.5%), but not the only species, in dust samples. The frequency of mites was found to be 21.4% in dust samples taken from the homes of these patients, and 17.5% of the house dust mite allergen could not be identified without microscopic examination. In this study, we have clearly shown that humidity and feeding animals increase the dust mite development risk by 1.74 and 1.82 times, respectively.

Conclusions
Dermatologists should request dust samples from patients with allergic problems for detailed examination such as microscopy or ELISA.