Rhipicephalus sanguineus tick allergy in asthmatic patients; diagnosis and immunotheraputic trial

ABSTRACT

Ticks belonging to the superfamily Ixodiodea have a potential role in allergic diseases including atopic skin diseases and atopic asthma. Tick extracts or vaccines were not prepared before, nor used in diagnosis or in specific immunotherapy of allergic patients. Therefore this study was carried out to diagnose and differentiate ticks allergy in asthmatic patients and to valuate the role of specific immunotherapy in those patients. The study included fourty patients with bronchial asthma and twenty healthy control persons. Patients were examined and classified according to their clinical staging [respiratory function test, presence of day time symptoms, exacerbations and presence of night time symptoms]. All subjects were investigated by skin prick test serum specific Ig E level, blood eosinophils and basophils phagocytic function test, lymphocytic population test and Immunogram including serum Ig M, and Ig G levels. After diagnosis of tick allergy by perivous investigations tick allergic patients were subjected to specific immunotherapy by tick vaccine using conventional updosing protocol by subcutaneous injection route and reevaluated both clinically and laboratory. Diagnosis of tick allergy was demonstrated by positive skin test and by highly significant statistical difference [P < 0.01] between patients and control group as regard the serum specific Ig E using tick extract. After immunotherapy the patients were clinicaly improved with highly statistical difference [P < 0.01] than before specific immunotherapy. Also, there were highly significant decrease [P < 0.01] in eosinophils count, basophils count, serum specific Ig E for tick allergen, and Ig M level while there were significant [P < 0.05] increase in phagocytic function test, lymphocytic populations test and Ig G level. Tick allergy was differentiated in Egyptian asthmatics and tick specific immunotherapy is highly successful in their management