Sous-types du virus de l'immunodéficience humaine de type 1 dans une cohorte de sujets dépistés à Saint-Étienne, France, de 1984 à 2003

Molecular characterization of non-B HIV type 1 isolates from patients of a department of infectious diseases, University Hospital of Bordeaux, France, 1989-2009

The molecular characterization of non-B HIV type 1 subtypes and the sociodemographic baseline characteristics have been studied for 114 non-B HIV-1-infected patients followed at the University Hospital of Bordeaux, France, and diagnosed as HIV infected between 1989 and 2009. Individuals enrolled in this study were mainly women with heterosexual transmission in West and Central Africa and who have been discovered to be HIV positive during pregnancy. Nevertheless, HIV acquisition among individuals born in France was significantly increasing. Recombinant form CRF02_AG was the most frequent subtype (38%) among a highly diverse viral background since 19 subtypes and CRFs have been characterized with a maximal diversity observed in the past decade.

Natural polymorphisms in HIV-1 protease: impact on effectiveness of a first-line lopinavir-containing antiretroviral therapy regimen

Mutations on HIV protease lead to resistance to protease inhibitors. However, resistance development may be different according to primary, secondary or polymorphic mutations. The present study was designed to assess the impact of natural protease mutations on the effectiveness of a first-line antiretroviral therapy (ART), and secondarily, their effect on the initial viral load (VL). The study was conducted in 175 HIV-1-infected patients, who initiated a first-line lopinavir/r-containing ART regimen and who had an available genotype resistance testing before initiating therapy. We assessed the association between mutations (prevalence > or = 10%) and the initial VL. We assessed the association between mutations and ART effectiveness using two surrogate markers: the slope of VL decrease at 1 month and the time to VL undetectability. For the 175 patients, the initial median VL was 4.94 log(10) copies/ml [interquartile range: 4.44-5.47] and the initial median CD4 lymphocyte count, 219/microl [129-296]. Eighteen mutations had a prevalence > or = 10%. At 1 month, the median VL decrease was 2.35 log(10) copies/ml [1.76-2.82]. The median time to VL undetectability was 128 days [91-196]. No mutation was associated significantly with the initial VL, the slope of VL decrease at 1 month or the time to VL undetectability. This study of antiretroviral-naive patients showed that protease polymorphisms had no impact on the effectiveness of a lopinavir/r-containing ART regimen. However, polymorphisms may affect ART effectiveness differently in other populations, such as ART-experienced patients and/or patients treated with protease inhibitors other than the one used here.

An outbreak of HIV-1 subtype G among Italian injecting drug users

We describe an outbreak of subtype G among injecting drug users (IDU) in northern Italy newly infected with HIV. We analysed pol gene sequences from samples of 139 individuals from different risk groups. Non-B subtypes were more frequently detected among IDU than in homosexual or heterosexual contacts. All G subtypes but one were found among IDU. The phylogenetic analysis indicated that the outbreak was of monophyletic origin and was caused by HIV-1 strains similar to those from western Africa.

Analysis of polymorphism in the protease and reverse transcriptase genes of HIV type 1 CRF02-AG subtypes from drug-naive patients from Saint-Etienne, France

SUMMARY

: The proportion of non-B HIV-1 variants is increasing in Western Europe. The impact of the high polymorphism in the protease and reverse transcriptase genes, as recently described for CRF02-AG isolates of African origin, on antiretroviral resistance is still disputed. We first examined the polymorphism of these genes in CRF02-AG strains recovered from drug-naive patients followed at the University Hospital of Saint-Etienne in France, most of these of French origin and harboring a clonal strain as elicited by phylogenic analysis. The first plasma sample detected positive from 31 CRF02-AG and 23 B strains was used to compare sequences with their respective subtype consensus strain. The overall number of mutations was dramatically higher for CRF02-AG strains than for B strains in both protease and reverse transcriptase genes (P < 0.0001 and 0.009, respectively). In addition, no statistically significant difference in the number of therapeutic failures, mean CD4 cell count, and viral load was observed between 22 and 45 patients infected with CRF02-AG or B strains, respectively, during a mean treatment period of 25.5 months. Even if no striking antiretroviral failure linked to this polymorphism was observed during short-term follow-up, its impact on long-term therapy will have to be extensively evaluated in patients infected by non-B HIV-1 variants.