Efficacy of High-Dose Trimethoprim-Sulfamethoxazol Prophylaxis on Early Urinary Tract Infection After Renal Transplantation

Urinary tract infection (UTI), a major cause of morbidity in renal transplant recipients, has also been found to increase mortality. The first month post-kidney transplantation is considered the critical time, with most UTI episodes during this period. The aim of this study was to compare the efficacy of various doses of trimethoprim-sulfamethoxazole (TMP/SXT) for the prophylaxis of the posttransplant UTI within the first month after kidney transplantation. In a prospective, double-blind, randomized, clinical trial, 95 kidney allograft recipients were divided into two groups: group 1 (n = 63) received low to moderate doses of TMP/SXT (either 80/400 mg or 160/800 mg, daily) and group 2 (n = 32), high doses of TMP/SXT (320/1600 mg, daily in two divided doses). These groups were comparable regarding age, gender, type of donor, and ureteral anastomosis and immunosuppressive therapy. UTI was defined as a urine culture containing more than 10⁵ colonies. The mean age of the patients was 37 ± 12.2 years with a male/female ratio of 0.98/1. The urine culture was positive in 39 patients (41.1%). UTI was more common among female than male patients (P = .003). Escherichia coli was the most common isolated organism in both groups (53.8%). UTI was observed in about 25% of patients on the high-dose versus 49.2% of those on low- to moderate-dose prophylaxis (P < .05). In conclusion, prophylaxis with high-dose TMP/SXT (320/1600 mg, daily) is preferred for renal transplant recipients during the first month posttransplantation.