Background: Some men who donate a kidney have reported testicular pain after donation; however, attribution to donation is not clear as no prior studies included a comparison group of nondonors. Objective: To examine the proportion of male donors who reported testicular pain in the years after nephrectomy compared to male nondonors with similar baseline health characteristics. Design, Participants, and Setting: We enrolled 1042 living kidney donors (351 male) before nephrectomy from 17 transplant centers (12 in Canada and 5 in Australia) from 2004 to 2014. A concurrent sample of 396 nondonors (126 male) was enrolled. Follow-up occurred until November 2021. Measurements: Donors and nondonors completed the same schedule of measurements at baseline (before nephrectomy) and follow-up. During follow-up, participants completed a questionnaire asking whether they had experienced new pain in their eyes, hands, or testicles; those who experienced pain were asked to indicate on which side of the body the pain occurred (left or right). The pain questionnaire was completed by 290 of 351 male donors (83%) and 97 of 126 male nondonors (77%) a median of 3 years after baseline (interquartile range 2, 6). Methods: Inverse probability of treatment weighting on a propensity score was used to balance donors and nondonors on baseline characteristics. After weighting, the nondonor sample increased to a pseudo sample of 295, and most baseline characteristics were similar between donors and nondonors. Results: At baseline, donors (n=290) were a mean age of 49 years; 83% were employed, and 80% were married; 246 (84.8%) underwent laparoscopic surgery and 44 (15.2%) open surgery; 253 (87.2%) had a left-sided nephrectomy and 37 (12.8%) a right-sided nephrectomy. In the weighted analysis, the risk of testicular pain was significantly greater among donors than nondonors: 51/290 (17.6%) vs. 7/295 (2.3%); weighted risk ratio, 7.8 (95% CI, 2.7 to 22.8). Donors and nondonors did not differ statistically in terms of self-reported eye pain or hand pain. Among donors, the occurrence of testicular pain was most often unilateral (92.2%) and on the same side as the nephrectomy (90.2%). Testicular pain occurred more often in donors who had laparoscopic vs. open surgery: 48/246 (19.5%) vs. 3/44 (6.8%) but was similar in those who had a left-sided vs. right-sided nephrectomy: 44/253 (17.4%) vs. 7/37 (18.9%). Limitations: Participants recalled their symptoms several years after baseline, and we did not assess the timing, severity, or duration of pain or any treatments received for the pain. Conclusion: Unilateral testicular pain on the same side of a nephrectomy is a potential complication of living kidney donation that warrants further investigation.

The authors have declared no competing interest.

This research was supported by a foundation grant awarded to Dr. Garg from the Canadian Institutes of Health Research (Funding Reference Number 148377). Dr. Naylor was supported by a Health System Impact Embedded Early Career Researcher Award Canadian Institutes of Health Research.

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