Hepatitis C associated mixed cryoglobulinemia glomerulonephritis in the setting of undetectable viral load: successful treatment with hydroxychloroquine and review of the literature.

There are an estimated 58 million cases of Hepatitis C (HCV) worldwide. Approximately 38-76% of individuals can develop extrahepatic manifestations such as mixed cryoglobulinemia (MC). Importantly, the appearance of symptoms due to MC is linked by detectable HCV RNA. A 38-year-old male with remote history of HCV infection diagnosed 8 years prior presented to the emergency department with subacute renal failure with proteinuria, hematuria, and WBC/RBC casts. Biopsy confirmed acute proliferative, non-crescentic, inflammatory glomerulonephritis. He also had new onset cryoglobulinemia. His HCV RNA was low-grade and liver function tests were all within the normal range. A liver biopsy showed signs of chronic hepatitis with mildly active portal fibrosis. The MC was cleared with steroids and a re-measured HCV RNA quantitative was negative. Seven months later, he was readmitted with glomerulonephritis and elevated MC. However, the patient's HCV viral load was undetectable. The patient underwent 6 rounds of plasmapheresis and 6 doses of Rituximab were given with suppression of cryoglobulin to nil. A month later, the MC levels rose again, while the viral load remained undetectable with the possibility of spontaneous remission. After initiation of maintenance hydroxychloroquine, his GFR improved to normal over the next 2 years. Multiple theories have been suggested for the phenomenon including presence of residual virus and lymphoproliferation effects. Hydroxychloroquine could be a successful option, though future studies should corroborate our outcome.