Background: Renal complication of leptospirosis is common and its clinical manifestations vary from urinary sediment changes to acute renal failure. The aim of this study was to determine the final outcome of renal involvement in leptospirosis.

Methods: This longitudinal prospective study included all serologically confirmed cases of leptospirosis with evidence of renal failure. All patients were followed for three months while all patients with renal failure were followed-up for one year.

Results: Fifty-one patients, 53.5±14.8 years (82.4% males) with acute renal failure were studied. Over the hospitalization period, 28 patients recovered, and seven (13.72%) patients died of multiple organ failure. At the time of discharge, 16 patients had mild renal failure. Over the follow-up period, all patients recovered but in two patients renal failure persisted at creatinine level of 1.5 mg/dl.

Conclusion: Development of renal failure in leptospirosis is not rare. Recovery of renal function may last several months. However, most patients recover completely at least after one year.