title: [Resistance to anti-retroviral therapy in Chilean patients with HIV-1 from 2002 to 2005].
abstract: BACKGROUND
  Resistance limits the effectiveness of anti-retroviral therapy. In Chile, there is free access to highly active anti-retroviral therapy since 2001, but there is no information about the frequency of mutations associated to drug resistance.
  
  
  OBJECTIVE
  To determine the most common mutations associated to anti-retroviral drug resistance in Chile.
  
  
  METHODS
  Retrospective study of 710 genotype analysis coming from 568 patients aged 22 to 70 years (85% males) with virological failure. The analysis was performed using a commercially available sequencing kit (Trugene HIV-1 genotypic assay from Bayer S.A).
  
  
  RESULTS
  Mean CD4(+) cell count and viral load were 154 cells/microl and 228784 RNA copies/ml, respectively. The frequency of resistance to nucleoside RT inhibitors (NRTI), non nucleoside RT inhibitors (NNRTI) and protease inhibitors (PI) was 71 %, 62% and 22%, respectively. The most common mutations found were T215Y (46%), L10F (44%), Ml84V (3896), K103N (35%) and M41L (32%). Fifty five percent of mutations corresponded to the TAM (thymidine analogue mutations) group. Multiresistance was 47% to NNRTI, 7% to NRTI, 4% to PI and 0.7% to all groups. During the four years of the study, there was a significant increase in NNRTI resistance.
  
  
  CONCLUSIONS
  These data provides important information about the epidemiology of drug resistance mutations and should help to design new HAART strategies.
authors.affiliation: Sección de Inmunología, Departamento de Medicina, Hospital Clínico, Universidad de Chile, Santiago, Chile. aafani@vtr.net
authors.forename: Alejandro
authors.initials: A
authors.lastname: Afani S
authors.forename: Laura
authors.initials: L
authors.lastname: Orellana R
authors.forename: Paula
authors.initials: P
authors.lastname: Duarte J
authors.forename: William
authors.initials: W
authors.lastname: Acevedo M
authors.forename: Ornar
authors.initials: O
authors.lastname: Morales B
authors.forename: Marcelo
authors.initials: M
authors.lastname: Wolff R
authors.forename: Patricia
authors.initials: P
authors.lastname: Vásquez
authors.forename: Carlos
authors.initials: C
authors.lastname: Beltrán
mesh_terms: D000328:Adult; D000368:Aged; D019380:Anti-HIV Agents / Q000627:therapeutic use*; D023241:Antiretroviral Therapy, Highly Active; D018791:CD4 Lymphocyte Count; D002677:Chile; D024921:Drug Resistance, Multiple, Viral / Q000235:genetics*; D005260:Female; D005838:Genotype; D015658:HIV Infections / Q000188:drug therapy / Q000821:virology*; D015497:HIV-1 / Q000187:drug effects / Q000201:enzymology / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics*; D011480:Protease Inhibitors / Q000627:therapeutic use; D012367:RNA, Viral / Q000032:analysis; D012189:Retrospective Studies; D018894:Reverse Transcriptase Inhibitors / Q000627:therapeutic use; D019562:Viral Load
chemical_list: D019380:Anti-HIV Agents; D011480:Protease Inhibitors; D012367:RNA, Viral; D018894:Reverse Transcriptase Inhibitors