Abstract: SA-PO0726
Essential Mixed Cryoglobulinemic Membranoproliferative Glomerulonephritis Masquerading as Cardiorenal Syndrome
Session Information
- Glomerular Diseases: Complement-Mediated Glomerulopathies and Infection-Related GN
October 24, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Authors
- Garza González, Ana Sofía, Tecnologico de Monterrey, San Pedro Garza García, Nuevo León, Mexico
- Navarrete, Claudia Aline, Tecnologico de Monterrey, San Pedro Garza García, Nuevo León, Mexico
- Riojas, Valeria, Tecnologico de Monterrey, San Pedro Garza García, Nuevo León, Mexico
- Salazar-Alejo, Misael, Tecnologico de Monterrey, San Pedro Garza García, Nuevo León, Mexico
- Maya-Quinta, Rogelio, Tecnologico de Monterrey, San Pedro Garza García, Nuevo León, Mexico
Introduction
Essential mixed cryoglobulinemia has become increasingly rare. In multimorbid patients, declining renal function may be attributed to more common conditions, delaying recognition of underlying glomerular disease.
Case Description
An 82-year-old man with chronic kidney disease, type 2 diabetes mellitus, hypertension, and prior transcatheter aortic valve replacement presented with edema and palpable purpura of the lower extremities. Initial evaluation revealed worsening kidney function from a baseline creatinine of 1.8 mg/dL to 2.6 mg/dL.Transthoracic echocardiography showed reduced ejection fraction with elevated NT-proBNP levels, favoring cardiorenal syndrome or progression of diabetic kidney disease. However, urinalysis demonstrated subnephrotic proteinuria and marked microscopic hematuria.
Expanded immunologic evaluation revealed positive cryoglobulins, elevated rheumatoid factor, and disproportionately low C4 levels. Kidney biopsy demonstrated immune complex-mediated membranoproliferative glomerulonephritis with hyaline thrombi and vasculitic features. Immunofluorescence revealed polyclonal IgG and IgM deposits with both κ and λ light chains, consistent with mixed cryoglobulinemic MPGN. Autoimmune, infectious, hematologic, and thoracoabdominal CT evaluation was unrevealing, supporting the diagnosis of essential mixed cryoglobulinemia.
Discussion
This case highlights the critical role of kidney biopsy in identifying uncommon but treatable causes of renal decline that may otherwise be attributed to more straightforward conditions such as cardiorenal syndrome. Cryoglobulinemic glomerulonephritis should remain in the differential diagnosis of hypocomplementemia with vasculitic manifestations and active urinary sediment. Careful interpretation of urinary and serologic findings is essential to avoid premature diagnostic closure.