title: Monitoring the BK virus in liver transplant recipients: a prospective observational study.
abstract: OBJECTIVE
  Because of the controversy regarding the effects of BK virus on nonrenal solid-organ transplant, we detected the BK virus via different methods and its effect on clinical findings, liver and kidney functions, and graft dysfunction in liver transplant recipients.
  
  
  METHODS
  This prospective cohort study comprised patients over the age of 18, who consecutively received liver transplant from January 1 to December 31, 2011. The patients were examined once, every 2 weeks, for the first 3 months after transplant. Clinical findings were evaluated on each examination; blood and urine samples were collected, BK virus DNA was assessed with real-time polymerase chain reaction, and the presence of decoy cells (which are epithelial cells with large nuclei and large basophilic inclusions) in the urine was investigated. Patients were followed-up for 1 year to see if rejection occurred.
  
  
  RESULTS
  Five of 39 patients (12.8%) showed BK viremia; 11 patients (28.2%) showed BK viruria, and 13 (33.3%) showed decoy cells. No statistically significant differences were found between BK virus positive and negative groups, respecting demographic variables, kidney and liver functions, and graft survival. BK virus DNA positivity in blood was the standard, while decoy cell assessment in urine and BK virus polymerase chain reaction test sensitivity in urine was 40%.
  
  
  CONCLUSIONS
  No matter the method used to detect BK virus in the urine, the negativity of the tests is more valuable than their positivity. Although no statistically significant difference was found between the groups, we concluded that BK virus is a factor that should be considered when unexplained deterioration in kidney and liver function tests is observed in liver transplant recipients. Prospective studies with larger numbers of patients are warranted.
authors.affiliation: From the Department of Infectious Diseases and Clinical Microbiology,Dokuz Eylul University Faculty of Medicine, Izmir, Turkey.
authors.forename: Kubra
authors.initials: K
authors.lastname: Demir-Onder
authors.forename: Vildan
authors.initials: V
authors.lastname: Avkan-Oguz
authors.forename: Tarkan
authors.initials: T
authors.lastname: Unek
authors.forename: Sulen
authors.initials: S
authors.lastname: Sarioglu
authors.forename: Ozgul
authors.initials: O
authors.lastname: Sagol
authors.forename: Ibrahim
authors.initials: I
authors.lastname: Astarcioglu
mesh_terms: D000328:Adult; D000368:Aged; D001739:BK Virus / Q000235:genetics / Q000302:isolation & purification*; D004279:DNA, Viral / Q000302:isolation & purification; D005260:Female; D006084:Graft Rejection / Q000175:diagnosis / Q000821:virology; D006085:Graft Survival; D006801:Humans; D016031:Liver Transplantation / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D027601:Polyomavirus Infections / Q000175:diagnosis / Q000652:urine / Q000821:virology*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D060888:Real-Time Polymerase Chain Reaction; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D014412:Tumor Virus Infections / Q000175:diagnosis / Q000652:urine / Q000821:virology*; D016482:Urinalysis; D014556:Urine / Q000166:cytology; D019562:Viral Load; D014766:Viremia / Q000175:diagnosis / Q000821:virology; D055815:Young Adult
chemical_list: D004279:DNA, Viral