Nontuberculous Mycobacterium Infection in Kidney Transplant Recipients: A Single Center Experience From North India

Abstract Background: Nontuberculous mycobacteria (NTM) are omnipresent in the environment. It is an important infectious complication in kidney transplantation (KT) due to an immunosuppressed state and has morbidity and mortality. Methods: Kidney transplantation recipients (KTR) with NTM infection were assessed for associative factors and outcomes in this retrospective observational study. Results: Amongst the 737 patients who underwent KT at our center between January 2011 and Jun 2023, five males and one female developed NTM infection. All had positive Ziehl Neelson (ZN) staining, negative GeneXpert test, and positive culture for NTM. The commonest site was subcutaneous infection. The mean age at NTM diagnosis was 29.5 ± 7.89 years. The median time of NTM infection from KT was 24 months (range, 4 – 113 months), and the median time of NTM confirmation from symptoms-onset was 27 days (range, 22 – 32 days). All had heightened immunosuppression i,e., recent deceased donor KT (DDKT) and anti-rejection treatment. The median time to development of NTM from DDKT/allograft-rejection was 21.5 months (4 – 40 months). The relative risk (RR) for NTM infection with exposure to anti-thymocyte globulin, rituximab, and mycophenolic acid was 12.6 (p=0.08), 10.3 (p=0.13), and 9.2 (p=0.13) respectively. All NTM patients were successfully treated; four had stable allograft function, whereas two had allograft failure. Conclusion: NTM infection was only seen in KTRs with heightened immunosuppression. A high index of suspicion and low threshold for mycobacterial culture is mandatory for early NTM diagnosis and good treatment response.