title: The prevalence of BK polyomavirus infection in outpatient kidney transplant recipients followed in a single center.
abstract: BACKGROUND
  BK polyomavirus (BKV) infection has emerged as an important cause of renal allograft loss. There is no proven therapy, and much basic clinical information is still lacking.
  
  
  METHODS
  We serially enrolled 95 outpatient renal transplant recipients (43% of whom were African American) in a single center cross-sectional screening study to determine the prevalence of BKV infection by whole blood polymerase chain reaction, and the prevalence of decoy cells by urinalysis and cytology. We also investigated the demographic and clinical factors associated with BKV infection, and the performance of urinalysis for decoy cells as a screening test for BKV infection.
  
  
  RESULTS
  The point prevalence of active BKV viremia was 7.4%. When subjects without active viremia but with a history of viremia and/or nephropathy were included, the overall prevalence was 15.8%. Urinary decoy cells were common, present in 50% of subjects at study entry. Urinalysis for decoy cells as a screen for BKV viremia had a sensitivity of 86%, specificity of 52%, positive predictive value of 13% and negative predictive value of 98%.
  
  
  CONCLUSIONS
  Decoy cells on urinalysis were the only factor independently associated with an increased risk of BKV infection on multivariate analysis. Although associated with BKV infection on univariate analysis, thymoglobulin, mycophenolate mofetil, and tacrolimus use were not independently associated with BKV infection on multivariate analysis, neither were history of acute rejection, gender, race, nor cause of end-stage renal disease.
authors.affiliation: Nephrology Service, Walter Reed Army Medical Center and Uniformed Services University of the Health Sciences, Washington DC, USA.
authors.forename: Fred E
authors.initials: FE
authors.lastname: Yeo
authors.forename: Christina M
authors.initials: CM
authors.lastname: Yuan
authors.forename: Sydney J
authors.initials: SJ
authors.lastname: Swanson
authors.forename: Bruce
authors.initials: B
authors.lastname: Reinmuth
authors.forename: Luana C
authors.initials: LC
authors.lastname: Kiandoli
authors.forename: Keith J
authors.initials: KJ
authors.lastname: Kaplan
authors.forename: Kevin C
authors.initials: KC
authors.lastname: Abbott
authors.forename: Joel C
authors.initials: JC
authors.lastname: Reynolds
mesh_terms: D000328:Adult; D000368:Aged; D001739:BK Virus / Q000276:immunology*; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D006084:Graft Rejection / Q000276:immunology / Q000821:virology*; D006801:Humans; D016867:Immunocompromised Host; D016030:Kidney Transplantation / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D027601:Polyomavirus Infections / Q000453:epidemiology / Q000276:immunology* / Q000652:urine; D011237:Predictive Value of Tests; D015995:Prevalence; D014412:Tumor Virus Infections / Q000453:epidemiology / Q000276:immunology* / Q000652:urine; D016482:Urinalysis; D014766:Viremia / Q000453:epidemiology; D017201:Virus Shedding