High correlation of human immunodeficiency virus type-1 viral load measured in dried-blood spot samples and in plasma under different storage conditions

Arch Med Res. Jul-Aug 2005;36(4):382-6. doi: 10.1016/j.arcmed.2005.03.010.

Abstract

Background: To measure HIV-1 RNA concentration requires venous extraction of blood, use of RNAase-free materials, and transport in a cold chain, which makes difficult the management of samples in developing countries. We evaluated the utility of the determination of HIV-1 RNA concentration in blood samples dried on filter paper (DBS) and subjected to different conditions, as contrasted with determination in plasma.

Methods: HIV-1 RNA concentration was determined in HIV-infected patients in DBS and in plasma samples. Samples were subjected to the following: DBS were stored at 4, 22, and 37 degrees C for 1, 3, and 7 days; samples from patients from four regions of Mexico were mailed to a reference laboratory; DBS were sent under environmental conditions; and plasma samples were sent frozen. HIV-1 RNA concentrations were determined by NucliSens in DBS and by Amplicor test in plasma.

Results: HIV-1 RNA concentration determined in DBS subjected to different temperatures and times had a significant correlation (r=0.99) with those obtained in plasma. When compared with values in plasma, Kappa agreement coefficients of values in DBS stored for 7 days at 4, 22, and 37 degrees C were 0.98, 0.83, and 0.94, respectively. Quantification of HIV-1 RNA in 108 DBS mailed from remote areas with different climates demonstrated significant correlation with those obtained in plasma (r=0.95; p <0.001).

Conclusions: DBS is a simple and reliable method to measure HIV-1 RNA concentration, especially when samples are mailed from remote areas to a reference center. This collection method is an economic and suitable alternative for use in developing countries.

Publication types

  • Multicenter Study

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Child
  • Child, Preschool
  • Female
  • HIV Infections / virology
  • HIV-1 / metabolism*
  • Hematocrit
  • Humans
  • Immunoenzyme Techniques
  • Male
  • Mexico
  • Middle Aged
  • RNA / chemistry
  • RNA / metabolism
  • RNA, Viral / chemistry
  • Reproducibility of Results
  • Reverse Transcriptase Polymerase Chain Reaction
  • Ribonucleases / metabolism
  • Specimen Handling
  • Temperature
  • Time Factors
  • Viral Load*

Substances

  • RNA, Viral
  • RNA
  • Ribonucleases