Abstract: FR-OR53
Clinicopathologic Features of Anti-Brush Border Antibody Disease: A Series of 66 Patients
Session Information
- Kidney Pathology: From Classic Clinicopathologic Studies to Computational Pathology
November 03, 2023 | Location: Room 109, Pennsylvania Convention Center
Abstract Time: 04:48 PM - 04:57 PM
Category: Pathology and Lab Medicine
- 1800 Pathology and Lab Medicine
Authors
- Murphy, Joel D., Arkana Laboratories, Little Rock, Arkansas, United States
- Caza, Tiffany, Arkana Laboratories, Little Rock, Arkansas, United States
- Cassol, Clarissa Araujo, Arkana Laboratories, Little Rock, Arkansas, United States
- Walker, Patrick D., Arkana Laboratories, Little Rock, Arkansas, United States
- Sharma, Shree G., Arkana Laboratories, Little Rock, Arkansas, United States
- Ambruzs, Josephine M., Arkana Laboratories, Little Rock, Arkansas, United States
- Boils, Christie L., Arkana Laboratories, Little Rock, Arkansas, United States
- Andeen, Nicole K., Oregon Health & Science University, Portland, Oregon, United States
- Palmer, Matthew, Penn Medicine, Philadelphia, Pennsylvania, United States
- Urisman, Anatoly, University of California San Francisco, San Francisco, California, United States
- Larsen, Christopher Patrick, Arkana Laboratories, Little Rock, Arkansas, United States
Background
Anti-brush border antibody disease (ABBA) is an autoimmune tubulointerstitial kidney disease that primarily affects older individuals and results in progressive kidney failure. It is a rare entity with only 20 cases reported to state. Therefore, the histopathologic spectrum, clinical associations, prognosis, and response to therapy are poorly understood.
Methods
We performed a retrospective clinicopathologic analysis of kidney biopsies and identified 66 cases with ABBA including 63 native and 3 recurrence in an allograft identified from 4 institutions. Demographics, clinical findings, and laboratory data were obtained. Histopathologic data included light, immunofluorescence, electron microscopy, and immunostaining for LRP2, CUBN, and AMN. Follow-up data was available from 49 patients, examining treatment(s), laboratory values, and outcome measures.
Results
Patients with ABBA were predominantly male (74%) with a mean age of 70.0 ± 12.3 years. Progressive chronic kidney disease was the most common biopsy indication. The mean serum creatinine was 3.5 ± 2.6 mg/dL, proteinuria 2.7 ± 2.9 g/day, and 66% had hematuria. Acute tubular injury with LRP2-positive tubular basement membrane deposits were seen in 94% patients, with one case demonstrating CUBN and AMN positivity in addition to LRP2. Thirty-eight patients (57.6%) had secondary diagnoses, most commonly glomerular diseases with high proteinuric states. These included podocytopathies, membranous nephropathy, IgA nephropathy, lupus nephritis, crescentic glomerulonephritis, acute or chronic tubulointerstitial nephritis, and renal involvement by B-cell lymphoma. The majority of patients with available follow-up data were treated with immunosuppression (73.5%). Complete or partial remission was achieved for 32.7%, 67.3% had no remission, and 22.5% required dialysis or were deceased at follow-up. Patients not treated with immunosuppression were at the highest risk of kidney failure.
Conclusion
ABBA is frequently concurrent with other kidney diseases, which may lead to under-diagnosis of this important cause of kidney failure.