International AIDS Society


HIV resistance surveillance on recently infected drug-naive patients from Argentina

A. Petroni1, G. Deluchi1, G. Lopardo2, I. Zapiola3, D. Pryluka4, M. Lázaro5, E. Chiocconi6, P. Elmassian2, H. Mingrone7, J. Martínez8, R. Bortolozzi9, J. Benetucci1

1Fundación de Ayuda al Inmunodeficiente (FUNDAI), Laboratorio de Retrovirus, Buenos Aires, Argentina, 2Centro de Estudios Infectológicos, Buenos Aires, Argentina, 3Htal. de Infecciosas 'F. J. Muñiz', Unidad de Virología, Buenos Aires, Argentina, 4Centro Medicus, Buenos Aires, Argentina, 5Htal. Zonal de Bariloche, Bariloche, Argentina, 6Htal. Provincial de Neuquén, Neuquén, Argentina, 7Htal. de Infecciosas 'F. J. Muñiz', Buenos Aires, Argentina, 8Htal. Británico, Buenos Aires, Argentina, 9Htal. Juan Bautista Alberdi, Rosario, Argentina

Background: Transmission of antiretroviral-resistant variants of HIV-1 to naive patients is becoming a great concern in clinical settings of developed countries. Here we present a surveillance study to estimate the occurrence of primary resistance in Argentina.
Methods: 123 recently infected drug-naive Argentinian subjects (97 men, 26 women) from Buenos Aires City and outskirts (76%) and other areas of Argentina (24%) were included. Recent infections were established from previous negative serology (48%), indeterminate western blot (34%), or the occurrence of acute retroviral syndrome after high-risk exposure (18%). The median time from probable infection date to genotyping was 3.0 months (range: 1 day to 8.7 months). Viral load was determined by RT-PCR. Viral RNA from plasma was retrotranscribed and a fragment of the pol gene, comprising the protease and the first 335 codons of the reverse transcriptase (RT), was sequenced. Phylogenetic analysis was implemented with ClustalX. Recombination analysis was performed by bootscanning with Simplot.
Results: Phylogenetic analysis resulted in 52 (42%) sequences from subtype B, 69 (56%) B/F recombinants (RecBF) and 2 (2%) uncommon mosaics (D/F and B/D). Resistance-related mutations (IAS-USA panel) were observed in 11/123 (8.9%) patients (95% confidence interval, 4.6%-15.4%): 0.8% to protease inhibitors (major mutations); 2.4% to nucleoside RT inhibitors; 4.9% to non-nucleoside RT inhibitors (NNRTIs), and 0.8% to all three drug classes (MDR). In this group, the estimated time from infection to genotyping (median, 4.1 months; range, 1 day to 8.2 months) was similar to that of the complete patient set. Resistance-related mutations seem to be more common in subtype B (8/52, 15%) than in RecBF (3/69, 4%) viruses (P=0.054) but resistant variants occurred in the same proportion among homosexuals and heterosexuals (10% each).
Conclusions: We found 8.9% of recently infected patients with primary HIV resistance in Argentina. Most of them (6/11) had NNRTIs-resistant viruses and one harbored a MDR variant.

Mexico City - AIDS 2008
Abstract no. 2008_TUPE0073

Suggested Citation
"A.Petroni, et al. HIV resistance surveillance on recently infected drug-naive patients from Argentina. : Mexico City - AIDS 2008: Abstract no. TUPE0073"

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