Infective endocarditis associated with acute renal failure: Repeat renal biopsy and successful recovery.

Infective endocarditis (IE) is a serious disease with a high associated mortality rate, particularly when complicated by acute renal failure (ARF). Although valve surgery and treatment with antibiotic agents are recommended, surgical options and the optimal therapy are not as yet well documented. Here, we report a rare case of IE in a young man with a history of intravenous drug abuse, who presented with high fever, bilateral thoracalgia, lower limb edema and renal dysfunction. After treatment with antibiotics, hemodialysis and anticoagulants, a tricuspid valve replacement surgery was performed on the patient. After surgery, his renal functions deteriorated and progressed to ARF. The first renal biopsy showed type II crescentic glomerulonephritis. After receiving continuous ambulatory peritoneal dialysis followed by administration of an angiotensin converting enzyme inhibitor and angiotensin receptor blockers, the patient's serum creatinine level decreased and the urine output increased gradually. In order to identify the renal turnover, we performed a second biopsy and found significant improvement in the pathological changes with endocapillary proliferative glomerulonephritis and fibrous crescents. Successful recovery of renal function was achieved 12 weeks after the initiation of therapy. Therefore, eradication of infection, tricuspid valve replacement and renal substitution therapy may be sufficient in some cases.