Abstract: FR-PO0691
Mixed Membranous Nephropathy Presenting as Severe Autoimmune Hemolytic Anemia
Session Information
- Glomerular Diseases: Membranous Nephropathy, FSGS, and Podocytopathies
October 23, 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
- Abdeltawwab, Mohannad, TriHealth Good Samaritan Hospital, Cincinnati, Ohio, United States
- Capriles, Guido M., TriHealth Good Samaritan Hospital, Cincinnati, Ohio, United States
- Rajput, Amit K., TriHealth Good Samaritan Hospital, Cincinnati, Ohio, United States
Introduction
Membranous nephropathy (MN) is classified as either idiopathic (primary) or secondary to systemic disease. Anti–phospholipase A2 receptor (anti-PLA2R) antibodies are highly specific for primary MN and are detected in approximately 70–75% of cases. Additional novel antibodies have been utilized to distinguish primary from secondary etiologies (ie, NELL-1 for malignancy and EXT1/EXT2 for autoimmune-associated MN). However, relying solely on serologic testing can be inconclusive. Rarely, features of both primary and secondary MN may coexist, as in our patient.
Case Description
A 63-year-old African American woman presented with profound normocytic anemia (Hb nadir 3.1 g/dL). After an unremarkable gastrointestinal evaluation, a positive direct antiglobulin test, and a bone marrow biopsy confirmed autoimmune hemolytic anemia (AIHA). Given a strong family history of SLE (daughter and granddaughter), coupled with high ANA/anti-dsDNA titers and low C3/C4, we were highly concerned for systemic lupus erythematosus (SLE) as the underlying cause of AIHA. Incidentally, urine testing demonstrated nephrotic-range proteinuria (UPCR 4.8g) in the setting of preserved GFR and absence of overt nephrotic symptoms, raising suspicion for class V lupus nephritis. Surprisingly, renal biopsy showed significant PLA2R deposition despite undetectable serum antibodies. The discordance between the clinical picture and the biopsy finding prompted biopsy reevaluation. Repeat staining demonstrated a “full-house” immunofluorescence pattern and EXT1 positivity, consistent with Class V Lupus Nephritis. Repeat testing showed anti-PLA2R seropositivity. Taking into account the clinical, serologic, and histopathologic data, the patient was diagnosed with Mixed Membranous Nephropathy. During initial management of AIHA, the patient was empirically initiated on high-dose prednisone and rituximab by Hematology. Despite 4 weeks on rituximab therapy, nephrotic range proteinuria persisted and progressed (UPCR 7.98g). Consequently, therapy was transitioned to cyclophosphamide as it can be utilized for both primary membranous and class V lupus nephritis.
Discussion
Coexistence of PLA2R-positive primary MN with class V lupus nephritis is exceptionally rare and poses diagnostic and therapeutic challenges, with no consensus on management. Our case highlights the limited efficacy of rituximab in this overlap. Cyclophosphamide is currently being trialed.