Mycobacterial infections after kidney transplant

We looked at mycobacterial infections occurring after a kidney transplant to determine incidence, risk factors, and outcomes. Of 3921 kidney transplants performed between 1984 and 2002, 18 (0.45%) (10 men, eight women; 11 cadaveric donor, seven living donor graft) were identified as having mycobacterial infection at some time posttransplant. Mean age at transplant was 38.3 years. Racial background was: Caucasian (n = 12), African-American (n = 2), Native Indian (n = 2), Hispanic (n = 1), and Middle Eastern (n = 1). The majority had a kidney alone (n = 14). Four recipients had simultaneous transplant of a second organ: pancreas (n = 2), islets (n = 1), and liver (n = 1). None of the 18 recipients had documented mycobacterial infection pretransplant. One recipient had a positive Mantoux test at the time of transplant and then developed pulmonary tuberculosis 4 months posttransplant; the remaining 17 patients had either negative (n = 10) or unavailable (n = 7) pretransplant Mantoux results. Mean time to infection was 3.2 years (range 1 week to 12 years). The most common site of infection was respiratory (n = 8). Other sites included musculoskeletal (n = 4), skin (n = 3), gyn (n = 1), and other (n = 2). Only three of the infections were with mycobacterial tuberculi; the others were with avium (n = 5), chelonae (n = 2), or other nontuberculous mycobacteria. Risk factors included previous TB exposure, occupational exposure, or accidental soft tissue injury. Soft tissue infections often presented as chronic unhealed wounds and required extensive surgical debridements. With mean follow-up of 12.5 years since transplant and 9.2 years since infection, 13 of the recipients are alive and well; causes of death included cardiovascular (n = 3) and sepsis (n = 2).