Abstract: SA-PO845
A Rare Case of Cryoglobulinemic Membranoproliferative Glomerulonephritis in the Setting of Negative Hepatitis Serologies
Session Information
- C3G, TMA, MGRS, Amyloidosis, and More
October 26, 2024 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Authors
- Papanagnou, Anastasios, NewYork-Presbyterian Hudson Valley Hospital, Cortlandt Manor, New York, United States
- Gupta, Sanjeev, Westchester Medical Center, Valhalla, New York, United States
Introduction
Membranoproliferative glomerulonephritis (MPGN) accounts for approximately 7-10% of all cases of biopsied glomerulonephritis, characterized (histologically) by mesangial hypercellularity, subendothelial deposition of immune complexes, and duplication of the glomerular basement membrane (tram-track appearance).
MPGN is classified as being mediated by immune complexes, complement dysregulation, or neither of the two. MPGN can be caused by chronic infections (especially hepatitis), autoimmune diseases, and paraproteins (including cryoglobulinemia).
Cryoglobulinemic MPGN is reported to be highly associated with chronic hepatitis C virus (HCV) infection but there are only a few case reports documenting cryoglobulinemic MPGN in the absence of chronic hepatitis.
Case Description
We present a case of an 81 y/o woman without any underlying hepatitis, with mild to moderate AS, CHF, HTN, LBBB, osteopenia, polymyalgia rheumatica, who presented to the hospital with worsening SOB and LE edema. Labs showed AKI with associated microscopic hematuria and nephrotic range proteinuria (Urine protein/creatinine ratio of 8.18). She was admitted for management of a CHF exacerbation, started on IV Lasix with improvement in her symptoms. Proteinuria work-up revealed ANA (+) 1:1280, C3 83 (mildly depressed), atypical p-ANCA pattern (1:640) and positive cryoglobulins. SPEP/serum immunofixation: no monoclonal proteins, serum FLC ratio 1.48. Blood cultures did not show any growth. HIV and Hepatitis B/C panels were both negative.
Renal biopsy showed diffuse endocapillary proliferative and focal crescentic glomerulonephritis with membranoproliferative features with IgM-dominant deposits, mild tubular atrophy, interstitial fibrosis and mild acute tubular injury.
The patient was started on a prednisone taper and mycophenolate.
She was subsequently discharged with close outpatient renal follow-up. Serial outpatient labs, over the span of 6 months, showed resolution of her AKI and microscopic hematuria, with dramatic improvement of her proteinuria down to trace levels.
Discussion
We discussed a rare case of cryoglobulinemic MPGN with strong IgM staining, without underlying hepatitis, which led to a positive outcome after receiving combination steroid/mycophenolate therapy. Moreover, there is still much to be learned about establishing the standard of care for managing cases, like this one, appropriately.