Prevalence of resistance mutations in antiretroviral-naive chronically HIV-infected patients in 1998: a French nationwide study

Objective: To estimate the prevalence of resistance-conferring mutations to antiretroviral drugs in previously untreated patients with chronic HIV-1 i nfection as a basis for French recommendations on viral genotyping before a ntiretroviral treatment initiation. Design: Resistance mutations were sought in samples from 404 patients seen in 23 specialized centres throughout metropolitan France in 1998. Methods: The protease and reverse transcriptase (RT) genes of plasma virion s were sequenced. Primary and secondary protease and RT gene mutations were identified from the International AIDS Society resistance testing - USA pa nel. Results: The prevalence of patients with primary and secondary mutations we re 3.7% (95% CI 1.7-5.7) and 50.3% (95% CI 45.0-55.6), respectively. The pr evalence of patients with mutations associated with resistance to nucleosid e RT inhibitors (NRTI) and non-nucleoside RT inhibitors was 3.3% (95% CI 1. 5-5.1) and 0.8% (95% CI 0.0-1.7), respectively. The prevalence of patients with NRTI primary mutations differed according to whether seropositivity ha d been diagnosed more or less than one year previously (0.2 versus 2.2% P = 0.023). Primary mutations associated with protease inhibitor resistance oc curred at a prevalence of 1.9% (95% CI 0.5-3.4) with no difference accordin g to the duration of known seropositivity. Conclusion: In France, in 1998, the prevalence of patients with primary mut ations associated with resistance to antiretroviral drugs was low. Genotypi ng before the initiation of therapy was not recommended in chronically HIV- 1-infected naive patients. A national sentinel survey of resistance in this clinical setting is performed regularly to update the recommendations for resistance testing. (C) 2001 Lippincott Williams & Wilkins.