title: Association Between the Polyomaviruses Titers and Decoy Cell Positivity Rates After Renal Transplantation.
abstract: BACKGROUND
  Urinary decoy cells develop after renal transplantation and their appearance is attributable primarily to the proliferation of polyomavirus types BK and JC. We measured the levels of these 2 viruses that cause decoy cells to appear in the urine.
  
  
  METHODS
  BK and JC virus levels were quantified in 1182 urine samples from 335 renal transplant patients using a multiplex Taqman real-time polymerase chain reaction assay. Forty-four samples were excluded from analyses because both viruses were present at ≥10(4) copies/mL. We analyzed the relationship between viral load and the presence of urinary decoy cells.
  
  
  RESULTS
  Decoy cells were observed in 237 of 1138 urine samples (21%) and the BK and JC viruses were positive in 205 (18%) and 455 (40%) samples, respectively. Decoy cells were observed in 0%, 21%, 67%, 87%, 100%, and 96% of urine samples when the BK viral load was <10(4), 10(4)-10(5), 10(5)-10(6), 10(6)-10(7), 10(7)-10(8), and ≥10(8) copies/mL, respectively; and in 1%, 13%, 41%, 59%, 87%, and 97% of urine samples when the JC viral load was <10(4), 10(4)-10(5), 10(5)-10(6), 10(6)-10(7), 10(7)-10(8), and ≥10(8) copies/mL, respectively.
  
  
  CONCLUSIONS
  BK virus more frequently triggered the appearance of decoy cells than did JC virus at equivalent viral titers.
authors.affiliation: Department of Urology, Nagoya University Graduate School of Medicine, Showa-ku, Nagoya, Japan. Electronic address: yfunahashi@med.nagoya-u.ac.jp.
authors.forename: Y
authors.initials: Y
authors.lastname: Funahashi
authors.affiliation: Department of Urology, Nagoya University Graduate School of Medicine, Showa-ku, Nagoya, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Kato
authors.affiliation: Department of Urology, Nagoya University Graduate School of Medicine, Showa-ku, Nagoya, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Fujita
authors.affiliation: Department of Urology, Nagoya University Graduate School of Medicine, Showa-ku, Nagoya, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Ishida
authors.affiliation: Department of Urology, Nagoya University Graduate School of Medicine, Showa-ku, Nagoya, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Mori
authors.affiliation: Department of Urology, Nagoya University Graduate School of Medicine, Showa-ku, Nagoya, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Gotoh
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001739:BK Virus / Q000302:isolation & purification*; D002648:Child; D005260:Female; D006801:Humans; D007577:JC Virus / Q000302:isolation & purification*; D007676:Kidney Failure, Chronic / Q000473:pathology* / Q000601:surgery / Q000821:virology*; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D027601:Polyomavirus Infections / Q000473:pathology*; D060888:Real-Time Polymerase Chain Reaction; D016482:Urinalysis; D014556:Urine / Q000166:cytology / Q000821:virology; D019562:Viral Load; D055815:Young Adult