Continuous sulfa prophylaxis for urinary tract infection in renal transplant recipients

During a 12 to 25 month follow-up period, 252 renal transplant recipients maintained with continuous sulfa prophylaxis were observed for evidence of bacteriuria. Although symptoms were rare, positive cultures were obtained in 6 percent of the patients who responded to conventional antibiotic outpatient therapy. Compared with sulfisoxazole, trimethoprim-sulfamethoxazole led to slightly fewer infections, especially with gram-negative organisms. Toxicity from sulfa was minimal and occasional leukopenia reversed by temporarily withholding azathioprine. Continuous sulfa prophylaxis in renal transplant patients is therefore safe and effective in minimizing the incidence of urinary tract infection, as well as other opportunistic infections known to be treatable by sulfa agents.