Over 30-yr Experience on the Management of Graft Stones After Renal Transplantation

Abstract

Background: Urolithiasis has been reported in up to 1.8% of patients after renal transplantation. Limited data are available regarding the treatment of such patients owing to this low prevalence.

Objective: To analyse a consecutive series of 2115 renal transplantations to elucidate the prevalence of renal graft stones (RGS) and their treatment.

Design, setting, and participants: A retrospective review was performed of a consecutive series of renal transplants from 1983 to 2017. Demographic and specific data regarding symptomatology, diagnosis, and treatment of RGS were recorded.

Outcome measurements and statistical analysis: Quantitative and qualitative variables were described. Differences in clinical variables were evaluated using unpaired t test. Statistical significance was set at p<0.05.

Results and limitations: In total, 51 patients (2.4%) were diagnosed with de novo RGS. Mean stone size was 9±6.5mm, 31.4% being multiple stones. The distal ureter was the most common location (49%). Treatment modalities were extracorporeal shock wave lithotripsy (ESWL; 43.1%), active surveillance (25.4%), retrograde ureteroscopy (URS; 17.6%), antegrade URS (3.9%), percutaneous nephrolithotomy (3.9%), open approach (3.9%), and urine alkalisation (2%). Seven (13.7%) patients developed complications: two haematuria, three urinary tract infection, one steinstrasse, and one sepsis. Median follow-up was 72 mo. Overall stone-free rate was 52.9%. No significant differences were observed between mean glomerular filtration rate before and after treatment (p=0.642). There were no cases of graft loss. Limitations include the retrospective nature of the study and limited number of patients.

Conclusions: RGS is an uncommon complication. ESWL, endoscopic surgery, and surveillance have been used to treat or follow up such patients. In well-selected patients, endourological surgery appears to achieve better outcomes. RGS does not have a long-term impact on graft function or graft survival.

Patient summary: It is uncommon to develop stones in the transplant kidney. If such stones are properly diagnosed, several minimally invasive treatment options can yield good results while maintaining good renal function.

Keywords: Endourology; Graft; Kidney transplant; Renal transplant; Stones; Transplantation; Urolithiais.