Hepatitis B virus-associated cryoglobulinaemia diffuse endocapillary proliferative glomerulonephritis: a case report and literature review.

Cryoglobulinaemia can manifest as fatigue, purpura, and joint pain, and can involve the kidneys and peripheral nervous system. Type II and mixed cryoglobulinemia cases are usually associated with hepatitis C virus infection and autoimmune diseases, and most cases reported outside China have been related to hepatitis C virus. The pathological manifestation of cryoglobulinaemia glomerulonephritis is always membranous proliferative glomerulonephritis or membranous nephropathy; other pathological types are rare. This current case report describes a female patient with hepatitis B virus (HBV)-associated cryoglobulinaemic glomerulonephritis. The patient had hepatitis B complicated with purpura, abnormal urinalysis and renal function. She was positive for rheumatoid factor and had decreased complement, and her blood cryoglobulin level was positive. The pathological findings were consistent with late-stage capillary proliferative glomerulonephritis, which improved after steroid, immunosuppressant and anti-HBV treatment.