Pretreatment HIV-1 drug resistance in Argentina: results from a surveillance study performed according to WHO-proposed new methodology in 2014-15.

BACKGROUND: In Argentina, current national guidelines recommend starting with NNRTI-based regimens. Recently, there have been some local reports regarding concerning levels of NNRTI-transmitted resistance, but surveillance has never been carried out at a national level. OBJECTIVES: To determine the prevalence of HIV drug resistance in people starting ART in Argentina using a WHO-proposed methodology. METHODS: This was a cross-sectional, nationally representative study. Twenty-five antiretroviral-dispensing sites throughout the country were randomly chosen to enrol at least 330 persons starting ART, to generate a point prevalence estimate of resistance-associated mutations (RAMs) with a 5% CI (for the total population and for those without antiretroviral exposure). All consecutive patients older than 18 years starting or restarting ART in the chosen clinics were eligible. Samples were processed with Trugene and analysed using the Stanford algorithm. RESULTS: Between August 2014 and March 2015, we obtained 330 samples from people starting ART. The mean ±â€ŠSD age was 35 ±â€Š11 years, 63.4% were male, 16.6% had prior antiretroviral exposure and the median (IQR) CD4 count was 275 cells/mm3 (106-461). The prevalence of RAMs found was 14% (±4%) for the whole population (3% NRTI-RAMs; 11% NNRTI-RAMs and 2% PI-RAMs) and 13% (±4%) for those without prior antiretroviral exposure (3%, 10% and 2%, respectively). The most common mutation was K103N. CONCLUSIONS: This surveillance study showed concerning levels of HIV drug resistance in Argentina, especially to NNRTIs. Due to this finding, Argentina's Ministry of Health guidelines will change, recommending performing a resistance test for everyone before starting ART. If this is taken up properly, it also might function as a continuing surveillance tool.

Very high incidence of syphilis in HIV-infected men who have sex with men in Buenos Aires city: a retrospective cohort study.

BACKGROUND: The incidence of sexually transmitted infections (STIs), particularly syphilis, is high and continues to rise among some populations, especially among men who have sex with men (MSM). Furthermore, a higher incidence of STIs has been reported in HIV-positive than in HIV-negative MSM. OBJECTIVE: To determine the incidence of syphilis in a cohort of men with HIV in Buenos Aires city. METHODS: Retrospective cohort study. We examined the records and visits made by men with HIV aged >18 years in our institution during a 1-year period. Venereal Disease Reference Laboratory (VDRL) results for all the men in our cohort during the study period were analysed. We considered a case of syphilis as incident if a person had a VDRL result of ≥16 DILS, provided that this was increased at least fourfold compared with a previous determination. All VDRL results ≤8 were investigated, and analysed together with the medical records, to determine if they were new cases. RESULTS: We analysed the VDRL results and the clinical records of 1150 men followed up in our centre during the study period. Mean age was 40.9 years. According to the definition used, we registered 171 new cases of syphilis-that is, an incidence of 14.9/100 patients/year (95% CI 12.9 to 17.0). No significant differences in incidence according to age group were found, but there was a trend towards a lower incidence in older men. Ten men had two new episodes during the study. CONCLUSIONS: The incidence of syphilis in this cohort of men with HIV (predominantly MSM) was very high. In addition to maintaining high surveillance for early diagnosis and treatment, it is necessary to implement newer and more effective measures to prevent syphilis and other STIs in this population.

Prevalence of HLA-B*57:01 allele in Argentinean HIV-1 infected patients.

Hypersensitivity reaction to abacavir (ABC hypersensitivity syndrome, AHS) is strongly associated with the presence of the HLA-B*57:01 allele. This study was designed to estimate the prevalence of HLA-B*57:01 allele in Argentinean HIV-1 infected patients. We analyzed the presence of HLA-B*57:01 allele in 1646 HIV-1 infected patients from different regions of Argentina. This allele was detected in 81 patients; most of them corresponded to patients living in the central region of the country. The prevalence of HLA-B*57:01 was 4.9%, similar to other Caucasian populations and higher than other data reported for South American populations. This strongly supports screening for the presence of HLA-B*57:01 in abacavir treatment of HIV-1 in our country.