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.