Kidney Week

Abstract: FR-PO0750

When Rejection Is Not the Answer: Parvovirus B19 Associated with Collapsing FSGS and Thrombotic Microangiopathy After Kidney Transplantation

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

• Ravi, Divya, University of California San Francisco, San Francisco, California, United States

Divya Ravi, MBBS

• Laszik, Zoltan G., University of California San Francisco, San Francisco, California, United States

Zoltan G. Laszik, MD, PhD

• Nwosu, Uchenna A., University of California San Francisco, San Francisco, California, United States

Uchenna A. Nwosu, MD

• Whelan, Adrian, University of California San Francisco, San Francisco, California, United States

Adrian Whelan, MBChB

Introduction

Collapsing focal segmental glomerulosclerosis (FSGS) and thrombotic microangiopathy (TMA) in a kidney allograft are associated with poor graft outcomes and a broad differential diagnosis. We describe a kidney transplant recipient with parvovirus B19–associated collapsing FSGS and TMA, a rare infectious cause for this presentation.

Case Description

A 34-year-old male with end-stage renal disease (ESRD) due to reflux nephropathy status-post second deceased donor renal transplant and on maintenance immunosuppression with tacrolimus, mycophenolate mofetil, and prednisone presented 15 months post-transplantation with nausea, vomiting, and diarrhea. He was found to have acute kidney injury (AKI) with creatinine of 2.5 mg/dL at presentation from a baseline of 1.1 mg/dl. Chest x-ray was notable for bibasilar ground glass opacities and consolidation. Hospital course was notable for worsening AKI with creatinine to 4 mg/dL, along with progressive hypertension and proteinuria up to 6.3 g/g from 0.4 g/g previously. He underwent a kidney allograft biopsy which showed collapsing FSGS as well as TMA. Tacrolimus was switched to cyclosporine, and the patient was treated with eculizumab. Infectious workup for ground glass opacities, including respiratory viral panel, CMV, and COVID, was negative; however, metagenomic next-generation sequencing resulted in parvovirus positivity. Parvovirus DNA in the blood was >10 x 10⁸ copies/ml. Immunosuppression was decreased, and he was treated with IVIG, following which parvovirus DNA levels decreased to <100 copies/ml. Both creatinine and proteinuria improved to 2.34 mg/dL and 0.5 g/g, respectively

Discussion

Parvovirus B19 is a rare but important cause of collapsing FSGS and TMA among kidney transplant recipients and should be considered together with other infections as a unifying diagnosis when both pathological lesions co-exist. Early recognition may guide appropriate treatment while avoiding diagnostic anchoring.