Abstract: FR-PO0761
Double-Positive Anti-GBM and Myeloperoxidase (MPO)-ANCA Disease in a 12-Year-Old Patient with Rapidly Progressive Glomerulonephritis
Session Information
- Glomerular Diseases: ANCA Vasculitis, Anti-GBM Disease, and Crescentic GN
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
- Salinas, Magali, The University of Tennessee Health Science Center, Memphis, Tennessee, United States
- Gerhold, Kerstin, The University of Tennessee Health Science Center, Memphis, Tennessee, United States
- Bjornstad, Erica C., The University of Tennessee Health Science Center, Memphis, Tennessee, United States
Introduction
Anti-glomerular basement membrane (GBM) and MPO+ anti-neutrophil cytoplasmic antibody (ANCA) vasculitis in isolation are rare in pediatrics; double positivity is extremely rare. The disease typically presents as rapidly progressive glomerulonephritis (RPGN) with pulmonary hemorrhage. We report a pediatric case of RPGN requiring dialysis.
Case Description
A 12-year-old male presented with a four-week history of cough, mild hemoptysis, gross hematuria, and severe acute kidney injury after treatment for atypical pneumonia one month prior. Initial creatinine was 3.67 mg/dL, peaking at 4.13 mg/dL. Urinalysis showed >100 RBCs with a urine protein/creatinine ratio of 19. CRP was 40.7 mg/L, hemoglobin 9.5 g/dL, and platelets 426,000/mcL. Complements were normal. Chest imaging showed multifocal pneumonia without cavitation. Empirically, he was started on intravenous pulse methylprednisolone and broad-spectrum antibiotics. He did not require oxygen.
On hospital day 6, anti-GBM was 1.8 (normal <0.9), and ANCA was 5.3 (normal <1). Kidney biopsy demonstrated pauci-immune crescentic glomerulonephritis with +MPO staining and minimal anti-GBM staining, moderate interstitial fibrosis and tubular atrophy with 11 of 32 globally sclerosed glomeruli. On hospital day 7, plasmapheresis was initiated every other day until anti-GBM serologies were negative, and cyclophosphamide induction was started. He required intermittent hemodialysis for about 2 weeks. He had partial renal recovery and has remained independent of dialysis for 3 weeks thus far (with creatinine continuing to fall).
Discussion
This case highlights a rare pediatric double-positive anti-GBM/MPO-ANCA vasculitis presenting as RPGN responsive to aggressive immunosuppression. Double-positive disease has been reported in <20 pediatric patients in the literature. Screening for anti-GBM antibodies is essential in pediatric RPGN, especially when pulmonary involvement is present. Despite moderate chronic changes on biopsy, this patient demonstrated renal recovery, consistent with KDIGO 2024 ANCA guidelines, which recommend induction therapy despite unfavorable histology. Early recognition and aggressive multimodal immunosuppression with steroids, plasmapheresis, and cyclophosphamide enabled dialysis independence and partial renal recovery. Even limited time off dialysis significantly improves pediatric quality of life.
Acknowledgment
We acknowledge pediatric nephrology, pathology, extracorporeal therapies, and multidisciplinary care teams for their contributions to patient care.