Unusual pleuropneumonia-like organisms isolated in a study of Trichomonas vaginalis from cases of chronic urethritis.

Recently a study was unidertaken to ascertain the bacterial flora of the male urethra and the relationship of Trichomonas vaginalis and pleuropneumonia-like organisms (PPLO) in male patients with chronic urethritis. The PPLO encountered in this study differed from those described in the literature in that they could not be isolated on PPLO agar (Difco) supplemented with PPLO serum fraction A. Isolation was accomplished on beef heart infusion agar (Difco) supplemented with 5 per cent defibrinated horse blood. Because of these findings it is important to inform those workers engaged in the laboratory isolation of PPLO that some strains may be overlooked due to their unusually fastidious growth requirement and when relying entirely on PPLO agar supplemented with serum fraction A. The morphology of the colonies, as influenced by type of medium, is also illustrated.