title: Relationship of cytomegalovirus load assessed by real-time PCR to pp65 antigenemia in organ transplant recipients.
abstract: BACKGROUND
  Cytomegalovirus (CMV) infection in immunocompromised patients can lead to viremia associated with morbidity and mortality. Monitoring of viral loads in blood is critical for initiating and monitoring antiviral treatment.
  
  
  OBJECTIVE
  Validate quantitative real-time PCR assay targeting the US17 and UL54 regions of the CMV genome for automated DNA and extraction and amplification.
  
  
  METHODS
  3422 blood specimens from organ transplant recipients, including longitudinal specimens from 12 organ transplant recipients, were tested by CMV PCR and pp65 antigenemia.
  
  
  RESULTS
  CMV PCR for both US17 and UL54, was more sensitive and detected CMV DNA earlier and for longer than the CMV pp65 antigenemia test. Using antigenemia results as a reference standard, an optimal cutoff of 500 normalized copies was calculated for both US17 and UL54 PCR targets based on high sensitivity, specificity, and positive and negative predictive values. CMV DNA levels tracked well with clinical symptoms, response to treatment, and antigenemia.
  
  
  CONCLUSIONS
  Detection of persistent increases in CMV DNA levels above 500 normalized copies by this real-time PCR assay is indicative of symptomatic CMV disease in organ transplant recipients. Quantitative real-time PCR for CMV DNA can be used in lieu of antigenemia for monitoring CMV infection and determining when to initiate preemptive treatment.
authors.affiliation: Clinical Virology Laboratory, University of Pittsburgh Medical Center, United States
authors.forename: Sonali K
authors.initials: SK
authors.lastname: Sanghavi
authors.forename: Kareem
authors.initials: K
authors.lastname: Abu-Elmagd
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: Keightley
authors.forename: Kirsten
authors.initials: K
authors.lastname: St George
authors.forename: Kathleen
authors.initials: K
authors.lastname: Lewandowski
authors.forename: Stephanie S
authors.initials: SS
authors.lastname: Boes
authors.forename: Arlene
authors.initials: A
authors.lastname: Bullotta
authors.forename: Ryan
authors.initials: R
authors.lastname: Dare
authors.forename: Maryann
authors.initials: M
authors.lastname: Lassak
authors.forename: Shahid
authors.initials: S
authors.lastname: Husain
authors.forename: Eun J
authors.initials: EJ
authors.lastname: Kwak
authors.forename: David L
authors.initials: DL
authors.lastname: Paterson
authors.forename: Charles R
authors.initials: CR
authors.lastname: Rinaldo
mesh_terms: D001331:Automation; D003587:Cytomegalovirus / Q000235:genetics / Q000302:isolation & purification*; D003586:Cytomegalovirus Infections / Q000175:diagnosis* / Q000821:virology; D004279:DNA, Viral / Q000235:genetics; D006801:Humans; D016377:Organ Transplantation / Q000009:adverse effects*; D010750:Phosphoproteins / Q000097:blood*; D016133:Polymerase Chain Reaction / Q000379:methods*; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D013997:Time Factors; D014763:Viral Matrix Proteins / Q000097:blood*; D014764:Viral Proteins / Q000235:genetics; D014766:Viremia
chemical_list: D004279:DNA, Viral; D010750:Phosphoproteins; D014763:Viral Matrix Proteins; D014764:Viral Proteins; C065418:cytomegalovirus matrix protein 65kDa