Mycobacterium simiae: a previously undescribed pathogen in peritoneal dialysis peritonitis.

Peritonitis is a major complication of peritoneal dialysis (PD). Coagulase-negative staphylococcus, Staphylococcus aureus , and Gram-negative bacteria cause the majority of these infections and usually are amenable to conventional antibiotic therapy, allowing continuation of PD. Mycobacterial and fungal peritonitis represent a more difficult clinical challenge. The infecting organism is often difficult to isolate and can rarely be eradicated without catheter removal. Immunocompromised patients are susceptible to opportunistic infection and, in the context of PD, may have PD peritonitis with different organisms from immunocompetent patients. Here the authors report for the first time PD peritonitis caused by Mycobacterium simiae , a nontuberculous mycobacterium, in a human immunodeficiency virus-positive patient. In addition the difficulty in diagnosing and managing nontuberculous PD peritonitis is discussed.