Retrospective Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Transplant. Dec 24, 2015; 5(4): 292-299
Published online Dec 24, 2015. doi: 10.5500/wjt.v5.i4.292
Clinical and pathological features of kidney transplant patients with concurrent polyomavirus nephropathy and rejection-associated endarteritis
Stephanie M McGregor, W James Chon, Lisa Kim, Anthony Chang, Shane M Meehan
Stephanie M McGregor, Anthony Chang, Department of Pathology, University of Chicago Hospitals, Chicago, IL 60637, United States
W James Chon, Department of Medicine, Section of Nephrology, University of Chicago Hospitals, Chicago, IL 60637, United States
Lisa Kim, Hawaii Pathologists’ Laboratory, Honolulu, HI 96813, United States
Shane M Meehan, Sharp Memorial Hospital, San Diego, CA 92123, United States
Author contributions: All authors contributed to data collection, analysis and writing of the manuscript.
Institutional review board statement: This study was reviewed and approved by the Biological Sciences Division/University of Chicago Medical Center Institutional Review Board at the University of Chicago (IRB14-0052).
Informed consent statement: Patients were not required to give informed consent to the study due the retrospective nature of the study. A waiver of consent is included in the IRB protocol.
Conflict-of-interest statement: We have no financial relationships or conflicts of interest to disclose.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Shane M Meehan, MB, BCh, Pathologist, Sharp Memorial Hospital, 7901 Frost Street, San Diego, CA 92123, United States. smmeehan414@gmail.com
Telephone: +1-858-9393660 Fax: +1-858-9393647
Received: June 10, 2015
Peer-review started: June 11, 2015
First decision: August 25, 2015
Revised: October 14, 2015
Accepted: November 10, 2015
Article in press: November 11, 2015
Published online: December 24, 2015
Processing time: 196 Days and 1.8 Hours
Abstract

AIM: To describe the clinicopathologic features of concurrent polyomavirus nephropathy (PVN) and endarteritis due to rejection in renal allografts.

METHODS: We searched our electronic records database for cases with transplant kidney biopsies demonstrating features of both PVN and acute rejection (AR). PVN was defined by the presence of typical viral cytopathic effect on routine sections and positive polyomavirus SV40 large-T antigen immunohistochemistry. AR was identified by endarteritis (v1 by Banff criteria). All cases were subjected to chart review in order to determine clinical presentation, treatment course and outcomes. Outcomes were recorded with a length of follow-up of at least one year or time to nephrectomy.

RESULTS: Of 94 renal allograft recipients who developed PVN over an 11-year period at our institution, we identified 7 (7.4%) with viral cytopathic changes, SV40 large T antigen staining, and endarteritis in the same biopsy specimen, indicative of concurrent PVN and AR. Four arose after reduction of immunosuppression (IS) (for treatment of PVN in 3 and tuberculosis in 1), and 3 patients had no decrease of IS before developing simultaneous concurrent disease. Treatment consisted of reduced oral IS and leflunomide for PVN, and anti-rejection therapy. Three of 4 patients who developed endarteritis in the setting of reduced IS lost their grafts to rejection. All 3 patients with simultaneous PVN and endarteritis cleared viremia and were stable at 1 year of follow up. Patients with endarteritis and PVN arising in a background of reduced IS had more severe rejection and poorer outcome.

CONCLUSION: Concurrent PVN and endarteritis may be more frequent than is currently appreciated and may occur with or without prior reduction of IS.

Keywords: Acute rejection; BK polyomavirus; Kidney transplant; Polyomavirus nephropathy

Core tip: Here we report the clinical and pathologic features of 7 cases of concurrent polyomavirus nephropathy (PVN) and endarteritis identified out of 94 renal allograft recipients who developed PVN over an 11-year period (7.4%). These cases arose both in the setting of a prior reduction in immunosuppression (IS) and without such a change. Therefore, concurrent PVN and endarteritis appears more frequent than currently reported in the literature and may occur with or without prior reduction of IS.