Hepatitis B-Related Cryoglobulinemia: A Case Report of Renal-Pulmonary Syndrome

Introduction: The World Health Organization estimates that approximately 296 million individuals were chronically infected with hepatitis B in 2019, with an annual incidence of 1.5 million new infections. Hepatitis B infection can lead to severe hepatic complications, including cirrhosis, liver failure and hepatocellular carcinoma. Rarely, patients with hepatitis B infection will develop extrahepatic manifestations such as mixed cryoglobulinemia. Case Description: 47-year-old man with untreated chronic hepatitis B (HBeAg negative) presented with hypoxia, pleuritic chest pain, hemoptysis, and pitting edema. He was noted to have a new normocytic anemia and a stage III AKI with proteinuria and hematuria on urine sediment. A CT pulmonary angiogram showed bilateral pleural effusion, pulmonary nodules and no evidence of embolism. Patient subsequently decompensated requiring intubation due to diffuse alveolar hemorrhage confirmed on bronchoscopy. His kidney biopsy was consistent with cryoglobulinemic glomerulonephritis and serum cryoglobulin testing was positive for mixed cryoglobulinemia. Patient was treated with intravenous pulse corticosteroids and started on entecavir. He responded well to the treatment and was successfully extubated. Following his course of intravenous corticosteroids, he was transitioned to high-dose oral prednisone once daily. His renal function returned to baseline and patient was discharged from hospital with outpatient follow-up. Discussion: This highlighted a case of HBV-related cryoglobulinemia with renopulmonary syndrome. Cryoglobulinemia is rarely seen in patients with hepatitis B infection and does not commonly lead to diffuse alveolar hemorrhage. Current guidelines recommend treatment for hepatitis B infection if there is evidence of liver injury either through elevated ALT or liver biopsy. The guidelines favor treating chronic hepatitis B infection with evidence of extrahepatic manifestations, however there are no recommendations on how to effectively screen patients. Diffuse alveolar hemorrhage is a life-threatening complication, and physicians should consider a lower threshold to treat patients with chronic hepatitis B infection. Given the rarity of HBV-related cryoglobulinemia with renopulmonary syndrome, there are no definitive guidelines on management; existing literature suggest treating with antiviral and corticosteroids, which was effective in this case.