Complete remission of minimal change disease after antiviral monotherapy in a patient with immune-active chronic hepatitis B

RATIONALE: Minimal change disease (MCD) is characterized by diffuse podocyte foot process effacement on electron microscopy, minimal structural changes on light microscopy, and the absence of immune complex deposition on immunofluorescence. In adults, MCD accounts for approximately 10% to 25% of nephrotic syndrome cases and is typically idiopathic, although secondary causes such as infections, medications, malignancies, and immune disorders have been reported. The association between hepatitis B virus (HBV) infection and glomerular disease has been well established in membranous nephropathy and mesangial proliferative glomerulonephritis. However, HBV-associated MCD is rare. PATIENT CONCERNS: A 42-year-old woman presented with a 1-week history of generalized edema and weight gain. Physical examination revealed severe bilateral pretibial pitting edema, and laboratory evaluation revealed hypoalbuminemia and nephrotic-range proteinuria. DIAGNOSES: The urine protein-to-creatinine ratio was elevated to 4.3, while renal function remained unchanged. Serological testing was positive for hepatitis B surface antigen and hepatitis B e-antigen, with a high viral load (HBV deoxyribonucleic acid 505,437 IU/mL), consistent with immune-active chronic hepatitis B infection. Renal biopsy showed nearly normal glomerular architecture on light microscopy, diffuse podocyte foot process effacement on electron microscopy, and no significant immune complex deposition on immunofluorescence, confirming MCD. INTERVENTIONS: Antiviral therapy with tenofovir alafenamide 25 mg orally once daily was initiated and continued throughout the 3-year follow-up period. OUTCOMES: Proteinuria progressively improved, and complete remission was achieved at 8 months (urine protein-to-creatinine ratio, 0.2). The patient maintained sustained remission with persistent viral suppression during a 3-year follow-up. LESSONS: Complete remission of MCD was temporally associated with antiviral monotherapy in a patient with immune-active HBV. Although potential confounding factors such as spontaneous remission or the supportive effects of concurrent angiotensin receptor blocker therapy cannot be entirely excluded, this case suggests that viral suppression may play a role in restoring podocyte function. Renal biopsy is essential for accurate diagnosis and treatment planning because corticosteroid therapy may exacerbate viral replication and hepatic injury. Antiviral monotherapy may represent a reasonable initial therapeutic strategy in select patients with biopsy-proven MCD and active hepatitis B infection.