Abstract: SA-PO1122
Collagenofibrotic Glomerulopathy in a Renal Transplant Patient
Session Information
- Transplant Trainee Case Reports
November 09, 2019 | Location: Exhibit Hall, Walter E. Washington Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Trainee Case Report
- 1902 Transplantation: Clinical
Authors
- Gilligan, Sarah, University of Utah, Salt Lake City, Utah, United States
- Raghavan, Divya, University of Utah, Salt Lake City, Utah, United States
- Revelo Penafiel, Monica Patricia, University of Utah, Salt Lake City, Utah, United States
- Abraham, Josephine, University of Utah, Salt Lake City, Utah, United States
Introduction
Collagenofibrotic glomerulopathy is a rare disease that can occur in childhood in an autosomal recessive inheritance pattern or sporadically in adults. It is non-immune mediated and is characterized by deposits of type III collagen in the mesangial and subendothelial areas of the glomeruli. Per prior case series, the average age of onset is 40 years. The rate of progression is variable and it sometimes results in end-stage renal disease.
Case Description
The patient is a 66 year old male with ESRD due to biopsy proven ANCA-negative pauci-immune crescentic glomerulonephritis, coronary artery disease, atrial fibrillation, and hypertension who underwent living unrelated renal transplant via paired exchange in December of 2016. His anti-rejection regimen was tacrolimus, everolimus, and prednisone. His post-transplant creatinine nadir was 1.5 -2.0 mg/dl but had slowly risen to 3.0 – 3.8 mg/dl in the months prior to evaluation. He had a negative DSA, low positive BK blood titers (peak of 244,000 copies/mL down to 838 copies/mL), and proteinuria of 500 – 1000 mg/g.
His renal transplant biopsy demonstrated chronic changes with 30% interstitial fibrosis and tubular atrophy and arteriolar hyalinosis secondary to calcineurin inhibitor toxicity with no evidence of transplant rejection. The glomeruli exhibited focal accumulation of PAS pale material in the capillary lumina and in the mesangium. Immunofluorescence was negative. On electron microscopy, there were subendothelial and mesangial deposits of curvilinear collagen fibrils compatible with collagenofibrotic glomerulopathy. Unfortunately, additional tissue was not available for immunohistochemical staining. The patient’s native renal biopsy was reviewed with no evidence of similar deposits. The donor’s records were also reviewed showing serum creatinine of 0.93 mg/dl with no significant proteinuria. The patient was transitioned from tacrolimus to belatacept with improvement in his serum creatinine to 2.34 mg/dl.
Discussion
Collangenofibrotic glomerulopathy is an extremely rare disease and in this case it is unclear whether it was donor derived or developed de novo after renal transplant. Renal biopsy of the donor would be the definitive diagnostic test but was not indicated with normal donor kidney function.