Abstract: SA-PO0873
Pauci-Immune Crescentic Glomerulonephritis in Primary Sjögren Syndrome: A Distinct Renal Manifestation
Session Information
- Glomerular Case Reports: ANCA, IgA, IgG, and More
November 08, 2025 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Authors
- Rivas Vega, Fabian Mauricio, Universidad Nacional Autonoma de Mexico, Mexico City, CDMX, Mexico
- Mendoza Rodríguez, María Fernanda, Universidad Nacional Autonoma de Mexico, Mexico City, CDMX, Mexico
Introduction
Primary Sjögren’s syndrome (pSS) is an autoimmune disorder characterized by lymphocytic infiltration of exocrine glands, leading to sicca symptoms, and, less frequently, systemic involvement. Renal disease in pSS most often manifests as tubulointerstitial nephritis, whereas glomerular lesions—particularly pauci-immune crescentic glomerulonephritis—are rare and typically associated with ANCA-positive vasculitis. We present a case highlighting an uncommon, immune-complex–independent glomerular injury in pSS, underscoring the importance of histopathological evaluation for accurate diagnosis and management .
Case Description
A 30-year-old woman without significant comorbidities presented with hypertensive crisis (180/110 mmHg) and rapidly deteriorating renal function. Initial laboratory tests revealed serum creatinine 4.23 mg/dL, blood urea nitrogen 51 mg/dL, proteinuria of 2.23 g/24 h, and microalbuminuria. Immunological work-up showed high-titer ANA (1:1000), anti-SSA positivity, and normal complement levels; both MPO-ANCA and PR3-ANCA were negative. Salivary gland biopsy confirmed focal lymphocytic sialadenitis(focus score 4/4 mm2). Renal biopsy demonstrated advanced global and segmental glomerulosclerosis, tubulointerstitial chronicity with severe fibrosis, and fibrocellular crescents without immune deposits by immunofluorescence—findings consistent with pauci-immune crescentic glomerulonephritis. High-dose intravenous corticosteroid pulses over three days led to partial recovery of renal function over a seven-day hospitalization .
Discussion
While tubulointerstitial nephritis is the hallmark renal lesion in pSS, glomerular injury due to immune complex deposition or pauci-immune vasculitis is uncommon. Pauci-immune crescentic GN in pSS may occur independent of detectable ANCA, representing a unique pathogenic subset requiring prompt recognition. Histological confirmation is critical to differentiate from cryoglobulinemic or membranous GN and to guide immunosuppressive therapy. Early intervention with corticosteroids—often combined with cytotoxic agents in ANCA-associated cases—can improve renal outcomes, although advanced fibrosis may limit recovery. This case highlights the need for vigilance for atypical renal presentations in pSS and reinforces the role of renal biopsy in ensuring accurate diagnosis and tailored treatment .