Polyomavirus nephropathy in renal allograft: prevalence and correlation of histology with graft failure.
BACKGROUND
While polyomavirus nephropathy (PVN) is recognized as an emerging cause of graft loss in renal transplants, the prevalence rate of PVN in renal grafts is unclear in Taiwan.


METHODS
Biopsies (n = 412) from 323 Taiwanese renal transplant patients were retrospectively analysed. PVN was diagnosed by the characteristic viropathic change in epithelial cells under light microscopic examination and a positive immunohistochemistry staining of anti-SV40 large T antigen. The viral cytopathic changes, interstitial inflammation, fibrosis and tubular atrophy were semiquantitatively assessed, based on the Banff 1997 classification and scoring for renal allograft.


RESULTS
Seventeen cases were identified with evidence of PVN; the prevalence rate is 5.26%. Compared with non-PVN patients, they were more likely to have had previous rejection episodes, higher graft loss and shorter graft survival.


CONCLUSIONS
This retrospective study showed that we have similar findings to other reports with at least 5% prevalence of PVN and that patients diagnosed early do better, while those diagnosed with severe inflammation or damage do worse or are likely to lose their grafts.
Wen
Mei-Chin
MC
Department of Pathology, Taichung Veterans General Hospital, Taichung, Taiwan.
Lian
Jong-Da
JD
Chang
Horng-Rang
HR
Shu
Kuo-Hsiung
KH
Wu
Ming-Ju
MJ
Chen
Cheng-Hsu
CH
Jan
Yee-Jee
YJ
Wang
John
J
Chang
Deching
D
D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006085:Graft Survival; D006801:Humans; D007150:Immunohistochemistry; D007674:Kidney Diseases / Q000473:pathology / Q000601:surgery* / Q000821:virology; D008297:Male; D008875:Middle Aged; D011120:Polyomavirus / Q000302:isolation & purification*