Examination of men with nongonococcal urethritis and their sexual partners for Chlamydia trachomatis and Ureaplasma urealyticum.

Chlamydia trachomatis was recovered from 39 (52%) of 75 men who had nongonococcal urethritis and from 28 (37%) of their sexual partners. Of the partners of men with Chlamydia-positive nongonococcal urethritis, 64% excreted Chlamydia, compared with 8% of the partners of men with Chlamydia-negative nongonococcal urethritis. In contrast, an apparently sexual mode of transmission was not observed with Ureaplasma urealyticum. Rates of recovery of U. urealyticum from men with nongonococcal urethritis whose cultures were Chlamydia-positive and those whose cultures were Chlamydia-negative were the same. Significant seroconversion was detected bythe single-antigen immunofluorescence test in about 50% of patients who had Chlamydia-postive cultures.