Acute onset of nephrotic syndrome during interferon-alpha retreatment for chronic active hepatitis C

A 57-year-old woman was scheduled to receive recombinant interferon-alpha retreatment for chronic active hepatitis C. During the course of therapy, the patient showed rapid onset of oliguria, dizziness, edema, and a pre-shock state. She was subsequently admitted to hospital and was diagnosed as having nephrotic syndrome. After admission, albumin-dominant proteinuria persisted despite the discontinuation of interferon therapy. Light microscopy of a renal needle biopsy specimen showed interstitial lymphoid cell infiltration, but no marked changes of the glomeruli and no staining for immunoglobulin or complement. Electron microscopy showed diffuse effacement of the glomerular epithelial foot processes, leading to a diagnosis of minimal change nephrotic syndrome with interstitial nephritis. Proteinuria resolved after the initiation of oral prednisolone therapy (1 mg/kg per day). The number of patients with chronic hepatitis C requiring interferon retreatment is increasing rapidly. We herein report this rare case of acute onset of nephrotic syndrome during interferon-alpha retreatment.