Fulminant type I cryoglobulinemic glomerulonephritis with unique ultrastructural plugs: a case report

Type I cryoglobulinemia is a rare disease which affects the skin, central nervous system and kidneys. It is usually associated with lymphoproliferative disorders such as multiple myeloma, lymphoma and monoclonal gammopathy of renal significance. Proteinuria and membranoproliferative glomerulonephritis are the most common renal manifestations; Case presentation: Here we report the case of a female patient in her late 40 s who had proteinuria accompanied by Raynaud's phenomenon, high blood and plasma viscosity, hearing loss, and cardiac and central nervous system involvement. Monoclonal immunoglobulin G-λ protein was detected and serum was positive for cryoglobulin. Renal biopsy revealed massive cryo-plugs with unique ultrastructural appearance in the glomerular and peritubular capillary lumina. Immunofluorescence showed predominant IgG3/λ deposition in cryo-plugs. As reported, the clinical manifestations of this patient resulted from cryoprecipitate and hyperviscosity syndrome; Conclusion: Cryoglobulinemia should be considered as a possible diagnosis in patients with Raynaud's phenomenon, hyperviscosity syndrome and monoclonal immunoglobulin.