Introduction: There have been some reports of transplant ureteral obstruction due to inguinal hernia after kidney transplantation (KT). This study aims to clarify the clinical features and the outcomes of ipsilateral inguinal hernia after kidney transplantation.

Method: From 2011 to 2020, eight patients who diagnosed as inguinal hernia on the ipsilateral side of KT were included in this study. We retrospectively reviewed those patient’s clinical data from medical records. All values were expressed as the median and range. This study was approved by the ethics committee of the Institutional Review Board.

Results: All patients were male. The age was 68 (range, 28 - 75) years. Of the eight patients, living donor KT was performed in 5 and deceased donor KT was performed in 3. The median post-transplantation period was 6.8 (0.5 - 18.0) years. Right side inguinal hernia was observed in all patients, including one case of bilateral inguinal hernia. Six patients were direct type and two were indirect type of inguinal hernia. The hernia contents were transplanted ureter and bladder in 2, transplanted kidney and ureter and small intestine in one, transplanted kidney and small intestine in one, bladder and small intestine in 3, and only bladder in one patient. Five out of 8 patients showed transplant urinary tract obstruction due to inguinal hernia. All hernias were repaired by using meshes (mesh plug method in 6, Lichtenstein method in 2). The operative time was 120 (86 - 155) minutes and blood loss was 7 (3 - 85) ml. Serum creatinine levels in five urinary obstructed patients were improved (p < 0.01) and transplanted urinary tract obstruction was disappeared after surgery. During follow-up period, no recurrence of inguinal hernia was observed and only chronic pain in the groin area (Clavien-Dindo grade II) was complicated in one patient.

Conclusion: According to the previous 23 published cases, the median age at presentation was 59 years and median post-transplantation period was 11.5 years. Right side inguinal hernia was 65%, and 91% of inguinal hernias were presented ipsilaterally to the graft. As initial treatment to avoid graft failure, percutaneous nephrostomy (61%) and ureteral stenting (39%) were frequently reported. Transplant ureteral obstruction due to inguinal hernia is a rare complication after kidney transplantation. However, transplant ureter or bladder herniation should be considered in the differential diagnosis of graft hydroureteronephrosis for preventing allograft loss. Surgical intervention for inguinal hernia after kidney transplantation was safe and effective treatment to prevent worsening kidney graft function.