Cryptosporidium infection after renal transplantation in an endemic area

BackgroundCryptosporidium is one of the common causes of infective diarrhea in post-transplant patients in endemic areas. However, data are limited on Cryptosporidium infection in recipients of solid organ transplantation. The aim of this study was to determine the incidence, disease manifestation, management, and outcome of Cryptosporidium infection in living-donor renal transplant recipients (RTR). MethodsWe performed a detailed retrospective review of the data on all RTR who had diarrheal illness requiring evaluation and hospitalization, and Cryptosporidium infection. ResultsDuring the study period, 119/1235 (8.98%) RTR developed diarrhea, and Cryptosporidium was found in 34/119 (28.5%). Nine of 680 (1.3%) patients were on a cyclosporine (CSA)-based regimen, and 25/643 (3.8%) patients were on a tacrolimus (Tac)-based regimen. The relative risk of developing Cryptosporidium infection was lower on the CSA-based regimen, compared with the Tac-based regimen (odds ratio [OR]: 0.35, 95% confidence interval [CI]: 0.17-0.72, P=0.003). Twelve of the 34 patients had acute graft dysfunction, mainly caused by combined Tac toxicity and dehydration. Mean serum creatinine and trough Tac level were 2.040.65mg/dL and 8.24 +/- 1.19ng/dL, respectively. Nitazoxanide alone was used in 13 patients, and nitazoxanide in combination with fluoroquinolone in 21 patients, with duration of treatment ranging from 16 to 60days. Tac was changed to CSA in 8/11 patients. The clearance of cysts and response to nitazoxanide alone were significantly lower, compared with combination therapy (61.53% vs. 95.23%, P=0.01, 38.46 vs. 85.71%, P=0.004, respectively). The OR for cyst clearance and response was also significantly lower with nitazoxanide alone, in comparison with combination therapy (OR: 0.65, 95% CI: 0.34-0.92, P=0.01, OR: 0.45, 95% CI: 0.21-0.81, respectively). Four (16%) of 24 patients with response had relapse. ConclusionPatients with Tac and mycophenolate mofetil combination therapy had a significantly high risk of Cryptosporidium infection. Cryptosporidial infection may require prolonged nitazoxanide therapy, either alone or in combination, with or without reduction in immunosuppression.