Component-resolved diagnosis (CRD) using microarray technology has recently been introduced with the aim to improve diagnosis of allergy. The aim of this study was to compare performance of this allergen microarray to those of an established extract-based skin prick testing (SPT).45 patients with allergic rhinitis were studied (16 children and 29 adults). SPT to Dermatophagoides pteronyssinus, Dermatophagoides farinae and Blomia tropicalis extracts and allergen microarray ImmunoCAP ISAC were carried out for all patients. Forty out of 45 patients demonstrated positive SPT to all mite extracts tested. These 40 patients were considered to be mite-allergic based on the positive SPT results. The remaining 5 patients with negative SPT to any mite extracts were classified as non-mite allergic. Comparatively, based on the microarray results, only 34 mite-allergic patients had detectable serum IgE to at least one of the mite allergen components tested whereas 6 patients with positive SPT to mite extracts showed no detectable IgE reactivity to any of the components tested. One non-mite allergic patient had a positive test- Blo t 5. Der p 10-positive patients also reacted to other cross-reactive tropomyosin from anisakis (Ani s 3) (25%), cockroach (Bla g 7) (50%) and shrimp (Pen m 1) (75%). CRD is a reliable tool for the diagnosis of allergy to mites. Der p 10 might be a useful indicator to identify a subset of mite-allergic patient that have additional sensitization due to cross-reactivity and thus allows selection of patients for immunotherapy.
Atopy is a syndrome characterized by immediate hypersensitivity reactions to common environmental antigens. The "hygiene hypothesis" stipulates that childhood infections are associated with a lower risk of allergies. Not much has been published about the effects that the treatment of pulmonary tuberculosis (TB) has on allergies, specifically allergic rhinitis. We conducted a study to investigate the prevalence of allergic rhinitis in patients with pulmonary TB before and after treatment of their TB. Our initial study group was made up of 121 patients with confirmed pulmonary TB who were followed up by questionnaire. In addition to demographic data, they provided information about their personal and family history of atopy and their current status with regard to allergic rhinitis. After providing informed consent, all patients underwent skin-prick testing with Dermatophagoides pteronyssinus, Dermatophagoides farinae, and Blomia tropicalis allergens before and after TB treatment. Stool samples were obtained to identify patients with worm infestation, and they were excluded from the study. In all, 94 patients completed treatment and follow-up, and their data were included in the final analysis. Of this group, 31 patients (33.0%) exhibited symptoms of allergic rhinitis prior to TB treatment, and 26 (27.7%) had a positive skin-prick test. Following treatment, only 12 patients (12.8%) reported allergic rhinitis symptoms (p = 0.004), but there was no significant reduction in the number of patients with a positive skin-prick test (n = 20 [21.3%]; p = 0.555). We conclude that the treatment of pulmonary TB results in significant relief of atopy, particularly allergic rhinitis symptoms.
Sensitization to mite and cockroach allergens is common, and diagnosis and therapy of allergy can be further complicated by the presence of allergen isoforms and panallergens. Purified recombinant and native allergens are useful for studies to resolve such problems.