title: Detection of HIV-1 in Saliva: Implications for Case-Identification, Clinical Monitoring and Surveillance for Drug Resistance.
abstract: BACKGROUND
  Saliva tests that detect antibodies are used to diagnose HIV infection. The goal of this study was to determine whether saliva could be used for nucleic acid-based tests to measure HIV-1 virus load (VL) and detect drug resistance.
  
  
  METHODS
  69 HIV infected individuals provided 5-10 ml of saliva and blood samples. Viral RNA was isolated from saliva and dried blood spots using the Nuclisens extraction. Saliva VL was measured using a modified Amplicor assay, and genotyping was performed using an in-house RT-PCR/sequencing protocol. Plasma VLs were obtained from concurrently drawn clinical tests.
  
  
  RESULTS
  Thirty-six of 47 (77%) plasma viremic patients had measurable saliva HIV-1 RNA. Paired plasma and saliva HIV RNA levels were significantly correlated (Spearman's correlation = .6532, p<.0001), but saliva VL was typically lower. Three of 22 patients with undetectable plasma VL (<50 copies/ml) had detectable saliva HIV RNA. Eleven of 30 patients with undetectable saliva RNA had detectable plasma HIV-1 RNA. Comparison of the protease and reverse transcriptase gene sequences from paired saliva and plasma of 20 patients showed less than 1% difference overall, and few resistance-related amino acid differences
  
  
  CONCLUSIONS
  Most patients with plasma virus >50 copies/mL had detectable saliva HIV RNA, and the genotypic data was highly concordant between saliva and plasma. In patients with high levels of plasma HIV RNA, saliva might be useful in identifying viremia and evaluating drug resistance.
authors.affiliation: Division of Infectious Diseases, Stanford University School of Medicine, 300 Pasteur Drive, Stanford, CA 94305, USA.
authors.forename: Maya
authors.initials: M
authors.lastname: Balamane
authors.forename: Mark A
authors.initials: MA
authors.lastname: Winters
authors.forename: Sudeb C
authors.initials: SC
authors.lastname: Dalai
authors.forename: Alexandra H
authors.initials: AH
authors.lastname: Freeman
authors.forename: Mark W
authors.initials: MW
authors.lastname: Traves
authors.forename: Dennis M
authors.initials: DM
authors.lastname: Israelski
authors.forename: David A
authors.initials: DA
authors.lastname: Katzenstein
authors.forename: Jeffrey D
authors.initials: JD
authors.lastname: Klausner