Evaluation of five immunodiagnostic techniques in echinococcosis patients.

Double diffusion (DD), indirect haemagglutination (IHA), immunoelectrophoresis (IEP), latex agglutination (LA), and complement fixation (CF) tests were evaluated for sensitivity and specificity in the diagnosis of 141 surgically-proven Turkana echinococcosis patients and 10 controls. The overall sensitivities for the tests were: IHA, 86.7%; LA, 53.3%; CF, 63.3%; DD, 55.0%; IEP, 55.0%. LA and CF tests produced a high number of false positive results; IHA gave a false positive result in 10% of cases; no false positives were obtained with IEP and DD. A combination of the latter three tests would therefore offer the best chance of detecting specific anti-Echinococcus antibodies, with an average sensitivity of 62.7%. The possible reasons for the relatively high incidence of false negative values are discussed.