Abstract: TH-PO612
Prevalence and Outcomes of Anti-Glomerular Basement Membrane Disease with and Without Secondary Glomerular Pathologies
Session Information
- Glomerular Diseases: Clinical and Epidemiologic Studies
November 02, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Trials
Authors
- Klomjit, Nattawat, Division of Nephrology and Hypertension, University of Minnesota, Minneapolis, Minnesota, United States
- Alexander, Mariam P., Depatment of pathology and laboratory medicine, Mayo Clinic, Rochester, Minnesota, United States
- Zand, Ladan, Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota, United States
Background
Anti-glomerular basement membrane (Anti-GBM) disease is a rare but devastating autoimmune kidney disease. Anti-GBM disease can co-exist with several other glomerular pathologies, but little is known about the frequency of these associated pathologies and patients’ renal outcomes compared to patients who have anti-GBM disease alone.
Methods
We retrospectively evaluated Mayo Clinic Renal Pathology Database and included patients (age ≥ 18 years) with a diagnosis of anti-GBM disease on a native kidney biopsy who were treated at the Mayo Clinic from 2000 to 2021. Detailed pathological findings were collected from renal pathology reports. Clinical characteristics and outcomes were collected from review of medical records.
Results
Total of 209 anti-GBM cases were identified and of these, 49 cases (23.4%) were treated at Mayo Clinic (internal), whereas 160 cases (76.6%) only had their biopsy reviewed at Mayo Clinic but were treated elsewhere (external). Of 209, 191 were typical anti-GBM (91.4%) and 18 (8.6%) were atypical anti-GBM. Of typical anti GBM cases (n=191), 119 (62.3%) had no other glomerular pathology, 53 cases (27.8%) also had anti-neutrophilic cytoplasmic antibody (ANCA)-associated glomerulonephritis (GN), 10 cases (5.2%) had membranous nephropathy (MN), 6 cases (3.1%) had IgA nephropathy, 3 cases (1.6%) had thrombotic microangiopathy (TMA) and 1 case (0.5%) had fibrillary glomerulonephritis). ANCA-GN patients were significantly older than patients with anti-GBM alone and had significantly higher serum creatinine (SCr) compared to patients with associated MN. Those with MN had significantly higher urinary protein compared to those with anti-GBM alone and those with ANCA-GN . Patients with ANCA-GN had the highest degree of sclerosis compared to other pathologies. Of the 49 internal cases, 32 (65.3%) required dialysis upon presentation and 91.7% survived at 1 year. Of those who required dialysis, only 9.1% discontinued dialysis. There were no different in the outcomes between groups.
Conclusion
Concomitant glomerular pathology is common among patients with anti-GBM disease and can occur in up to 40% of patients. ANCA-GN accounts for over 70% of those co-existing pathologies. Clinical characteristics may potentially serve as clues to look for secondary pathologies in patients who present with anti-GBM disease.