Performance of an in-house genotypic antiretroviral resistance assay in patients pretreated with multiple human immunodeficiency virus type 1 protease and reverse transcriptase inhibitors.
An in-house genotypic antiretroviral resistance assay was evaluated by testing 32 plasma samples obtained from heavily pretreated human immunodeficiency virus type 1 (HIV-1)-infected patients failing multiple antiretroviral regimens. The same samples were also sent to Virco Laboratories for genotypic (VircoGEN) and phenotypic (Antivirogram) resistance analysis. Sequencing results obtained by in-house (HG) and VircoGEN (VG) genotyping were concordant for 387 of 400 (96.75%) drug resistance mutations. Genotype-based prediction of drug susceptibility for 13 currently licensed antiretroviral compounds were in agreement in 336 (80.78%) cases, partially concordant in 73 (17.54%) cases and discordant in only seven (1.68%) cases. VG indicated 'possible resistance' twice as much as HG. When genotype interpretation was compared with the Antivirogram phenotypic data, there were 27 (6.49%) and 23 (5.52%) wrong calls by HG and by VG, respectively. Both assays were more sensitive in detecting drug resistance than drug susceptibility (94.61 vs. 65.19% for HG, 80.84 vs. 56.91% for VG) and more specific in detecting drug susceptibility than drug resistance (93.62 vs. 73.49% for HG, 93.62 vs. 80.32% for VG). Rule-based algorithms can reliably interpret genotypic data obtained from most heavily pretreated patients. However, occasional genotypic patterns may be erroneously interpreted without resistance phenotyping.
Peduzzi
C
C
U. O. Malattie Infettive, Ospedale S.M. Annunziata, Firenze, Italy.
Pierotti
P
P
Venturi
G
G
Romano
L
L
Mazzotta
F
F
Zazzi
M
M
D019380:Anti-HIV Agents / Q000627:therapeutic use*; D023241:Antiretroviral Therapy, Highly Active; D024882:Drug Resistance, Viral / Q000235:genetics*; D005838:Genotype; D015658:HIV Infections / Q000097:blood / Q000188:drug therapy / Q000821:virology*; D016333:HIV Protease / Q000235:genetics*; D017320:HIV Protease Inhibitors / Q000627:therapeutic use*; D054303:HIV Reverse Transcriptase / Q000235:genetics*; D015497:HIV-1 / Q000145:classification / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics; D006801:Humans; D016133:Polymerase Chain Reaction / Q000379:methods; D011933:Reagent Kits, Diagnostic; D018894:Reverse Transcriptase Inhibitors / Q000627:therapeutic use*
D019380:Anti-HIV Agents; D017320:HIV Protease Inhibitors; D011933:Reagent Kits, Diagnostic; D018894:Reverse Transcriptase Inhibitors; D054303:HIV Reverse Transcriptase; D016333:HIV Protease