Abstract

Background: Tuberculosis (TB) is a common cause of morbidity and mortality in renal transplant recipients. It is usually misdiagnosed because of lack of medical awareness and its infrequency in renal transplant recipients. Materials and Methods: 44 cases (0.3) with post-transplant TB out of 12820 patients who had renal transplants performed between 1984 to 2003 were found from the hospital records of 12 major kidney transplantation centers in Iran. These cases were compared with 184 healthy transplant subjects whose transplants were performed by the same surgical team as the controls. Results: The mean age of cases and controls was 37.7 (13-63) and 35.6 (8-67) years (p=0.3), respectively. The mean duration of pre-transplantation hemodialysis was 30.3 (3-168) months in cases and 18.2(1-180) months in controls (p=0.03). A past history of tuberculosis was detected in 2 cases and 1 control (p=0.3). The mean doses of initial and maintenance immunosuppressive drugs in cases and controls were not significantly different. A total of 25 cases (56.8) and 60(32.6) controls had rejection prior to diagnosis of TB (p=0.004; OR=2.7, Cl95 1.3-5.6). Conclusion: To our knowledge, this is the first study that demonstrated increasing risk of post-transplant TB by extending the duration of pre-transplant hemodialysis and the number of post-transplant rejection episodes. Further study is needed to clarify our new findings specifically in respect of different immunosuppressive regimens. © 2006 NRITLD, National Research Institute of Tuberculosis and Lung Disease, Iran.