Evaluation of an enzyme immunoassay for detection of Neisseria gonorrhoeae in an adolescent population

Abstract

We compared a modified procedure of Gonozyme , an enzyme immunoassay for detection of gonococcal antigen in urogenital specimens, with bacterial culture for Neisseria gonorrhoeae in a hospital-based adolescent clinic. In 839 patients studied, prevalence of urogenital gonorrhea by culture was 14.3%. The sensitivity of the immunoassay was 90.0%, and the specificity was 98.1%; predictive values for a positive and a negative test result were 88.5% and 98.3%, respectively. Gonozyme was highly accurate in 57 males studied; sensitivity, specificity, and predictive values were 100%. In 782 females, sensitivity was 87.5%, specificity was 98.0%, positive predictive value was 85.7%, and negative predictive value was 98.2%. Patients with false-negative immunoassay results had lower colony counts on culture. Gonozyme is an acceptable substitute for culture in males and in females with intermediate or high prevalence of gonorrhea. Results can be available within three hours.