Chronic hepatitis B triggering antineutrophil cytoplasmic antibody-associated vasculitis complicated by glomerulonephritis: A case report.

Background: Hepatitis B virus (HBV) infection can lead to renal involvement, commonly manifested as HBV-associated glomerulonephritis (HBV-GN), which typically presents as nephrotic or nephritic syndrome. Antineutrophil cytoplasmic antibody-associated vasculitis (AAV) is a systemic disease characterized by immune necrotizing inflammation of small blood vessels involving multiple organs with complex and severe clinical implications. The coexistence of HBV-GN and AAV is sporadic, with limited data existing regarding its diagnosis, management, clinical outcomes, and prognosis, especially in patients with AAV.

Case summary: This manuscript presents the case of an older male patient who presented with persistent foamy urine lasting over two weeks. Initial clinical findings included nephrotic syndrome and renal insufficiency, which subsequently progressed to involve the lungs, immune system, hematologic system, and other organ systems. The patient was diagnosed with HBV-GN complicated by AAV, a rare and complex condition. Despite receiving comprehensive treatment, including corticosteroids, cyclophosphamide for immune regulation, plasma exchange, and immunoadsorption targeting antineutrophil cytoplasmic antibody-associated antibodies, the patient required long-term dialysis and demonstrated a poor prognosis.

Conclusion: HBV infection may trigger nephropathy with AAV. Early recognition and intervention are crucial for improving patient prognosis.