Urethral inflammation in male chimpanzees caused by ureaplasmas and Chlamydia trachomatis.

Specimens from men with acute non-gonococcal urethritis were tested to determine their microbial content and then given intra-urethrally to male chimpanzees. Two animals received ureaplasmas only and one became infected. The second did so when given a different strain. Both developed a polymorphonuclear leukocyte (PMNL) response. Two chimpanzees received a mixture of ureaplasmas and Chlamydia trachomatis and there was a suggestion that the ureaplasmas delayed or suppressed the chlamydial response. The latter, that is urethral infection with a pronounced PMNL response, was most clearly seen in a chimpanzee given C. trachomatis only. No inflammation was detected in two chimpanzees acting as controls. Three of five chimpanzees given ureaplasmas genitally, and one that had them endogenously, had them transiently in the oropharynx about 2 weeks later. The occurrence of ureaplasmas in the conjunctiva of three chimpanzees inoculated at this site was also transient and without inflammation. The possibility that Mycoplasma genitalium might have been in the inocula and caused urethral inflammation was discounted largely because no animal had antibody to this mycoplasma.