Diagnostic value of late cutaneous response to Casoni test in patients operated for echinococcus cyst

Thirty-eight patients with confirmed Echinococcus cysts were evaluated postoperatively. RAST as well as early and late skin responses to Echinococcus antigen were assessed. Early skin responses were positive in most of the patients even 10 years or more postoperation. Late skin responses were positive in 42% of the patients, and the younger the patient, the greater the likelihood of occurrence. In patients who had late skin responses, the reactions were similar at 4 to 8 and 24 hours following the antigen. These results suggest that late skin responses seen at 24 hours are part of the immediate hypersensitivity reaction to the antigen.