Mycoplasma hominis septic arthritis: two case reports and review.

Mycoplasma hominis is normally a commensal of humans. When the organism is pathogenic, it primarily causes disease in the genitourinary tract. Septic arthritis caused by M. hominis is a rare condition that occurs chiefly in the postpartum period, in immunosuppressed hosts, or in patients who have recently undergone urinary tract manipulation. Arthritis caused by M. hominis is clinically indistinguishable from septic arthritis caused by other bacteria. Diagnosis is often delayed because infection with this organism is not suspected or because it grows slowly, if at all, in routine culture media. Appropriate therapy often leads to a good outcome, although relapses and resistance have been reported.