Anaphylactic shock to Argas reflexus bite.

Anaphylaxis is a severe, life-threatening allergic reaction, affecting both children and adults. The occurrence of anaphylaxis is not as rare as generally believed (1.21% to 15.04% of the US population). Often the cause of this reaction remain unknown, mainly due to the difficulty in defining the outbreaking causes. Herein, we describe an interesting case of a patient, who developed an anaphylactic reaction after the bite of a pigeon tick. During the last 2 years, in wintertime, the patient often came to the emergency room for general rash and swelling, hypotension and tachycardia preceded by itching and general distress. Notably, the symptoms manifested themselves as night fell. In two particular occasions the patient reached the hospital in a state of shock. After another episode of general swelling, the patient was invited to examine her domestic environment. She brought us some parasites, collected at home, particularly on the bed. A morphological examination by entomologists proved these parasites to belong to Argas reflexus (Arg.r.), one of the 31 species of soft ticks. The presence of specific IgE to a protein secreted by the Arg.r. salivary glands was in favour of immediate-type systemic reaction, as supposed by the clinical history.