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PubMed · 9189210

Subtype-specific problems with quantification of plasma HIV-1 RNA.

A Alaeus·K Lidman·A Sönnerborg·J Albert
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Abstract

OBJECTIVE: To determine whether two commercial assays for quantification of plasma HIV-1 RNA levels detect different genetic subtypes of HIV-1 with equal efficiency. DESIGN: Blind testing of stored plasma samples from 95 individuals infected with different genetic subtypes of HIV-1 (27 subtype A, 24 B, 18 C, 18 D, two E, two G, two H, and two J). The HIV-1 subtype had previously been determined by direct sequencing of the V3 domain of the env gene. METHODS: One plasma sample from each individual was tested once by the Roche HIV monitor assay and once by the Organon nucleic acid sequence-based amplification (NASBA) HIV-1 RNA quantitative assay, according to the manufacturers' recommendations. Information about CD4+ lymphocyte counts and antiretroviral treatment was available. RESULTS: The results from the two assays were strongly correlated with each other for subtypes B, C and D, but not for subtype A because many samples had RNA levels close to or below the lower detection limit of the assays. Thus, 15 out of 27 (56%) subtype A samples were negative by the HIV monitor assay and 12 (44%) were negative by the NASBA assay. These frequently occurring negative results among subtype-A-infected individuals were not due to better immunological status, more aggressive antiretroviral treatment, or differences in sample storage conditions. CONCLUSIONS: The HIV monitor assay and, possibly to slightly lesser degree, the NASBA assay appear unable to accurately quantify HIV-1 RNA levels in plasma samples from many subtype-A-infected individuals. These problems are likely to be due to primer mismatches and they limit the possibility of using these assays for routine monitoring of HIV-1-infected individuals in many parts of the world.

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CD4 Lymphocyte CountEvaluation Studies as TopicFollow-Up StudiesGenotypeHIV Envelope Protein gp120HIV InfectionsHIV-1HumansPeptide FragmentsProspective StudiesRNA, ViralReagent Kits, DiagnosticViral LoadComparative StudyJournal Article

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A Alaeus, K Lidman, A Sönnerborg, J Albert. 1997. Subtype-specific problems with quantification of plasma HIV-1 RNA.. https://doi.org/10.1097/00002030-199707000-00004

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