title: A new real-time quantitative PCR for diagnosis and monitoring of HIV-1 group O infection.
abstract: The correct diagnosis and monitoring of HIV-1 group O (HIV-O) infection are essential for appropriate patient management, for the prevention of mother-to-child transmission, and for the detection of dual HIV-M/HIV-O infections. HIV-O RNA quantification is currently possible with two commercial kits (from Abbott and Roche), which quantify HIV-M and HIV-O strains indifferently; therefore, they cannot be used for the specific identification of HIV-O infection. We designed a new real-time quantitative reverse transcription PCR (RT-qPCR assay) (INT-O), which we compared with our previous version, LTR-O, and with the Abbott RealTime HIV-1 kit. Specificity was assessed with 27 HIV-1 group M strains and the prototype strain of group P. Clinical performances were analyzed by using 198 stored plasma samples, representative of HIV-O genetic diversity. Analytical sensitivity, repeatability, and reproducibility were also determined. The detection limit of the INT-O assay was 40 copies/ml, and its specificity was 100%. The repeatability and reproducibility were excellent. Analysis of clinical samples showed a good correlation between the INT-O and LTR-O assays (r = 0.8240), with an improvement of analytical sensitivity. A good correlation was also obtained between the INT-O and Abbott assays (r = 0.8599) but with significantly higher values (0.19 logs) for the INT-O method, due to marked underquantifications for some patients. These results showed that HIV-O genetic diversity still has an impact on RNA quantification. The new assay, INT-O, allows both the specific diagnosis of HIV-O infection and the quantification of diverse HIV-O strains. Its detection limit is equivalent to that of commercial kits. This assay is cheap and suitable for use in areas in which strains of HIV-1 groups M and O cocirculate.
authors.affiliation: Laboratoire Associé au Centre National de Référence du VIH, Hôpital Charles Nicolle, CHU de Rouen, Rouen, France. Marie.Gueudin@chu-rouen.fr
authors.forename: Marie
authors.initials: M
authors.lastname: Gueudin
authors.forename: Marie
authors.initials: M
authors.lastname: Leoz
authors.forename: Véronique
authors.initials: V
authors.lastname: Lemée
authors.forename: Fabienne
authors.initials: F
authors.lastname: De Oliveira
authors.forename: Aurélia
authors.initials: A
authors.lastname: Vessière
authors.forename: Anfumbom
authors.initials: A
authors.lastname: Kfutwah
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Plantier
mesh_terms: D005838:Genotype; D015658:HIV Infections / Q000175:diagnosis* / Q000821:virology*; D015497:HIV-1 / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D019562:Viral Load / Q000379:methods*