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Abstract: SA-PO877

A Case of BK Virus-Associated Nephropathy in a Heart Transplant Patient

Session Information

Category: Transplantation

  • 2002 Transplantation: Clinical


  • Merchant, Paul T., Cleveland Clinic, Cleveland, Ohio, United States
  • Tomaszewski, Kristen, Cleveland Clinic, Cleveland, Ohio, United States
  • Nurko, Saul, Cleveland Clinic, Cleveland, Ohio, United States

BK virus associated nephropathy (BKVAN) causes allograft dysfunction in kidney transplant patients but is rarely reported as a cause of native kidney dysfunction in non-kidney solid organ transplant (NKSOT) patients. Treatment for BKVAN is limited, and reducing immunosuppression is the most common strategy. In NKSOT patients, the prevalence of BKVAN is not known but appears to be rare. We report a case of BKVAN in a heart transplant patient.

Case Description

A 26-year-old male with hypoplastic left heart, who underwent orthotopic heart transplant 9 years prior, presented with anemia and AKI. Post-transplant history showed no episodes of rejection requiring treatment and no kidney disease. Immunosuppression was tacrolimus 2mg BID and mycophenolic acid 360mg BID without recent changes. At presentation, patient had a hemoglobin of 7.2g/dL, and an evaluation for gastrointestinal bleeding was negative. The patient also had AKI with serum creatinine of 4.32mg/dL from 0.88mg/dL five months prior. Workup showed bland urinalysis, unremarkable urine sediment examination, and negative hemolysis studies. The AKI failed to improve with conservative management, so kidney biopsy was performed which showed chronic tubulointerstitial nephritis, severe interstitial fibrosis and tubular atrophy, and negative immunofluorescence. Testing for serum BK virus was positive with 1.21 million copies/mL. The biopsy underwent immunostaining for polyomavirus marker SV40, which was positive in 15% of tubules. A diagnosis of BKVAN was made. The patient’s mycophenolate was reduced by half, but serum BK viral load and creatinine remain elevated.


BKVAN is an important cause of allograft dysfunction in kidney transplant patients, but prevalence in NKSOT patients is less understood and likely underestimated. As this case demonstrates, BKVAN should be part of the differential diagnosis in NKSOT patients with CKD/AKI.

Positive immunostain for polyomavirus marker SV40.