Abstract: SA-PO0789
Antiphospholipid Syndrome Nephropathy with Concurrent ANCA-Negative, Pauci-Immune Crescentic Glomerulonephritis in a Patient with Rheumatoid Arthritis
Session Information
- Glomerular Diseases: Lupus Nephritis, Monoclonal Gammopathy-Related Disease, and Transplantation
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
- Lagman, Jozen Mesina, St. Luke's Medical Center Global City, Taguig, Philippines
- Valencia, Lee-Boyd Dampil, St. Luke's Medical Center Global City, Taguig, Philippines
- Chicano, Sonia Lim, St. Luke's Medical Center Global City, Taguig, Philippines
- Dimatulac, Aileen Agbanlog, St. Luke's Medical Center Global City, Taguig, Philippines
- Lagac, Mark Lawrence Majillo, St. Luke's Medical Center Global City, Taguig, Philippines
Introduction
Antiphospholipid syndrome (APS) nephropathy is commonly associated with thrombotic microangiopathy (TMA). Concurrent ANCA-negative pauci-immune crescentic glomerulonephritis (PICGN) is rarely reported. We describe a case of overlapping APS nephropathy and ANCA-negative PICGN.
Case Description
A 68-year-old Filipino female with hypertension, type 2 diabetes mellitus, and seropositive rheumatoid arthritis presented with vomiting, diarrhea, epigastric pain, and fever. Imaging showed acute calculous cholecystitis. Workup revealed severe AKI with creatinine 8 mg/dL from 0.73 mg/dL one month prior. Urinalysis showed dysmorphic red blood cells and nephrotic-range proteinuria (UPCR 15.39 g/g). Serologies revealed low C3, elevated C4, positive ANA, and positive lupus anticoagulant, while ANCA was negative. Renal biopsy demonstrated PICGN with 72% cellular crescents and minimal immune-complex deposits. Additional findings included TMA and acute tubular injury. APS nephropathy was diagnosed on positive lupus anticoagulant and biopsy-proven TMA.
Discussion
This was a diagnostic challenge and highlights the importance of considering glomerular disease in patients with severe AKI even if initial presentation is gastrointestinal. It also emphasizes that ANCA negativity does not exclude PICGN. Renal biopsy remains crucial in rapidly progressive kidney injury, particularly in patients with mixed clinical and serologic findings.
PAS stain - Diffuse crescentic glomerulonephritis with multiple glomeruli showing cellular crescents
Immunofluorescence microscopy showing trace granular mesangial staining