Du Bois D, Young S, Mills R, Mitchell PS, Persing DH; Conference on Retroviruses and Opportunistic Infections.
Program Abstr 4th Conf Retrovir Oppor Infect Conf Retrovir Oppor Infect 4th 1997 Wash DC. 1997 Jan 22-26; 4th: 178 (abstract no. 615).
Cenetron Diagnostics, Austin, TX.
Introduction: Quantitative amplification assays for plasma HIV-1 RNA are rapidly gaining acceptance in the management of HIV infected patients, and are being performed in an increasing number of clinical laboratories. To assess the precision of the Roche HIV-1 Monitor assay, and develop a rationale for defining a lower cutoff value for the assay, we conducted a blinded, three-way comparison of 100 specimens representing a wide range of plasma HIV RNA levels at 3 separate laboratories. Methods/Results: Baseline plasma specimens were collected from 424 patients attending a community clinic and frozen at -70C in multiple aliquots within 2 hours of venipuncture. Initial HIV RNA levels were determined at Cenetron Diagnostics, and followed a normal distribution with a mean of 184,500 (log 5.2) HIV RNA copies/mL. Twenty arcHIVed specimens from each 1.0 log interval (log 2.0-6.0 HIV RNA copies/mL; 100 total specimens) were selected at random, and were blindly tested at 2 additional laboratories (UNMMC and Mayo Clinic). The standard deviation of the log(10) (SD log(10)) for all specimens above 400 HIV copies/mL was 0.19, and the coefficient of variation (COV) was 41%. COV was highest (57%) among samples in the HIV RNA interval of log 2.6 - 3.0 RNA copies/mL, and lowest (30%) in samples in the range of log 4.0 -5.0 RNA copies/mL. Average linear regression of each individual laboratory's values vs. the two comparative laboratories was R=.98 (p is less than .0005). Of the 300 HIV RNA determinations, 6 (2%) were outliers (greater than log 0.5 difference than the mean of the 2 comparative values), and one PCR reaction failed. Summary: This study indicates that the HIV Monitor assay has its highest degree of precision in the range of HIV RNA levels between 10,000 and 100,000 HIV RNA copies/mL (SD log(10)=.14, COV=30%), and a small number of samples (2%) are outliers in a 3 way interlaboratory comparison. This assay system has ample precision to reliably detect 0.5 log changes in HIV RNA levels, an benchmark clinical parameter; and readily allows direct comparison of results generated from different laboratories.
Publication Types:
Keywords:
- AIDS Vaccines
- Acquired Immunodeficiency Syndrome
- Biological Assay
- Evaluation Studies
- HIV
- HIV Infections
- HIV Seropositivity
- HIV-1
- Humans
- Polymerase Chain Reaction
- RNA
- RNA, Viral
- Reagent Kits, Diagnostic
- instrumentation
- methods
- reverse transcriptase, Human immunodeficiency virus 1
Other ID:
UI: 102223620
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