title: Primary HIV-1 drug resistance in Spain before and after the introduction of protease inhibitors.
abstract: The prevalence of genotypic resistance to nucleoside analogues was examined in 150 naive individuals with chronic HIV-1 infection acquired before June 1996, when protease inhibitors began to be used in Spain, and in a group of 52 recent seroconverters infected since 1997. Overall, the prevalence of subjects carrying nucleoside-resistant genotypes was similar in both groups (12.6% and 15.4%, respectively). A polymorphism at codon 70 accounted for more than half of cases (63.1%) in naive individuals infected before protease inhibitors became available, in contrast most recent seroconverters carried genotypes with one or more key nucleoside resistance mutations, mainly associated with lack of sensitivity to zidovudine or lamivudine (prevalence 9.6% and 5.9%, respectively). When only key mutations were considered in each of the two periods, the prevalence of nucleoside-resistant genotypes was increased significantly among recent seroconverters (13.5% vs. 4.7%; P<0.05). The relatively high rate of resistance to nucleosides in Spain justifies the introduction of drug resistance testing in naive recent seroconverters before beginning antiretroviral therapy.
authors.affiliation: Service of Infectious Diseases, Instituto de Salud Carlos III, Madrid, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Pérez-Olmeda
authors.forename: J
authors.initials: J
authors.lastname: Del Romero
authors.forename: A
authors.initials: A
authors.lastname: Rubio
authors.forename: L
authors.initials: L
authors.lastname: Ruiz
authors.forename: C
authors.initials: C
authors.lastname: Rodríguez
authors.forename: M
authors.initials: M
authors.lastname: Leal
authors.forename: B
authors.initials: B
authors.lastname: Clotet
authors.forename: V
authors.initials: V
authors.lastname: Soriano
mesh_terms: D019380:Anti-HIV Agents / Q000494:pharmacology* / Q000627:therapeutic use; D003062:Codon; D004352:Drug Resistance, Microbial; D005838:Genotype; D017320:HIV Protease Inhibitors / Q000494:pharmacology; D006679:HIV Seropositivity / Q000188:drug therapy / Q000453:epidemiology / Q000821:virology*; D015497:HIV-1 / Q000187:drug effects* / Q000235:genetics; D006801:Humans; D019259:Lamivudine / Q000494:pharmacology; D009154:Mutation; D011110:Polymorphism, Genetic; D015995:Prevalence; D018894:Reverse Transcriptase Inhibitors / Q000494:pharmacology; D013030:Spain / Q000453:epidemiology; D015215:Zidovudine / Q000494:pharmacology
chemical_list: D019380:Anti-HIV Agents; D003062:Codon; D017320:HIV Protease Inhibitors; D018894:Reverse Transcriptase Inhibitors; D019259:Lamivudine; D015215:Zidovudine