Serological studies on the role of Chlamydia in the aetiology of non specific urethritis

Abstract

Sera from 103 men with nonspecific urethritis (NSU) were examined for chlamydial antibodies by the radioisotope precipitation (RIP) and microimmunofluorescence (IF) tests. Of 74 men with NSU from whom a chlamydial agent had been isolated, 70 (94%) gave positive results (titres ≥ 1:32) with the RIP test. By the use of the IF test, 64 of the 74 men (86%) gave positive results (titres ≥ 1:8) for IgG antibodies, and 21 (28%) positive results for IgG antibodies. Sera from 29 men with NSU from whom a chlamydial agent had not been isolated were also examined. Of these, 16 (55%) gave positive results with the RIP test, 7 (24%) with the IF IgG test, and 1 (3%) with the IF IgM test. These figures did not differ significantly from those obtained from a control group of 37 men with no history or clinical evidence of NSU. It is concluded from this preliminary study that both the RIP and the IF tests may be of value in demonstrating antibodies in the sera of patients with chlamydial genital infection. Serological evidence of recent chlamydial infection was rarely obtained from patients with NSU unless Chlamydia had been isolated on cell culture.