Intensive adherence counselling for HIV-infected individuals failing second-line antiretroviral therapy in Johannesburg, South Africa.

OBJECTIVE: In resource-limited settings, where genotypic drug resistance testing is rarely performed and poor adherence is the most common reason for treatment failure, programmatic approaches to handling treatment failure are essential. This study was performed to describe one such approach to adherence optimisation. METHODS: This was a single-arm study of patients on second-line protease inhibitor (PI)-based antiretroviral therapy (ART) with a HIV-1 RNA ≥400 copies/ml in Johannesburg, South Africa, between 1 March 2012 and 1 December 2013. Patients underwent enhanced adherence counselling. Those with improved adherence and a repeat viral load of >1000 copies/ml underwent HIV-1 drug resistance testing. We describe results using simple proportions and 95% confidence intervals. RESULTS: Of the 400 patients who underwent targeted adherence counselling after an elevated viral load on second-line ART, 388 (97%) underwent repeat viral load testing. Most of these (n = 249; 64%, 95% CI 59-69) resuppressed (<400 copies/ml) on second line. By the end of follow-up (1 March 2014), among the 139 (36%, 95% CI: 31-41%), who did not initially resuppress after being targeted, 106 had a viral load >400 copies/ml, 11 switched to third line, 5 were awaiting third line, 4 had died and 13 were lost to follow-up. Among the unsuppressed, 48 successfully underwent resistance testing with some resistance detected in most (41/48). CONCLUSIONS: Most (64%) second-line treatment failure in this clinic is related to adherence and can be overcome with careful adherence support. Controlled interventions are needed to determine what the optimal approach is to improving second-line outcomes and reducing the need for third-line ART.

Development of a simple microarray for genotyping HIV-1 drug resistance mutations in the reverse transcriptase gene in rural Tanzania.

OBJECTIVE: Aiming at a simple, inexpensive and robust tool for HIV-1 drug resistance genotyping during antiretroviral therapy (ART) we developed and validated a microarray-based detection of 25 drug resistance mutations most relevant for the Tanzanian ART regimen. METHODS: A reverse transcriptase gene fragment was reverse-transcribed and amplified by reverse transcription-polymerase chain reaction (RT-PCR). Primers for mini-sequencing were designed based on alignments of the most prevalent local HIV-1 variants. Tagged primers were extended by fluorochrome-labelled dideoxynuclotide triphosphate (ddNTPs) to indicate the single-nucleotide polymorphism (SNP) allele of the sample tested, followed by hybridisation on treated microarray slides. Images were analysed with a laser scanner and genotype calling was performed using in-house developed software. RESULTS: The microarray was validated with four cloned HIV-1 genome fragments from a Swiss HIV-1 cohort and 102 HIV-1 sequences amplified from the Tanzanian target population (field samples). Results were concordant with the Sanger sequencing SNP profile in 92.7% of 2550 SNP data points compared. Lack of signals in small number of SNPs was due to either failure in the extension reaction or hybridisation owing to mismatches between PCR product and extension primer. CONCLUSION: Our study demonstrates the feasibility of hybridisation-based genotyping of drug resistance mutations of HIV, even though our microarray, which was designed for population studies, achieved only correct assignment of 92% of all SNPs in the tested samples.

Comportamiento de los alelos HLA-DQB1*02 y HLA-DQB1*03 en pacientes con diagnóstico presuntivo de enfermedad celíaca / Behavior of HLA-DQB1*02 and HLA-DQB1*03 alleles in patients with a presumptive diagnosis of celiac disease

La enfermedad celíaca (EC) es autoinmune y se observa en individuos genéticamente predispuestos, se caracteriza por la intolerancia a determinadas proteínas llamadas gluten (gliadinas y gluteínas) que se encuentran en el trigo, el centeno y la cebada. Se sabe que existe una asociación del sistema HLA y la enfermedad celíaca (HLA-DQ2/HLA-DQ8), pero no existen estudios cubanos acerca de esa asociación por lo que nos propusimos analizar el comportamiento de los alelos DQB1*02 y DQB1*03 mediante un estudio analítico observacional en 65 pacientes con diagnóstico presuntivo de enfermedad celíaca con el objetivo de incluir la detección de estos alelos en el esquema diagnóstico de esta compleja enfermedad. Se halló que los individuos portadores del alelo DQB1*02 (OR: 2,26) fueron más susceptibles de padecer la enfermedad que los no portadores, que el 60 por ciento de los presuntos pacientes con enfermedad celíaca presentaron el alelo HLA-DQ2 y el 3 por ciento, el alelo HLA-DQ8. Se concluyóque el genotipaje HLA-DQ2/HLA-DQ8 es de gran utilidad para el diagnóstico de enfermedad celíaca

The celiac disease (CD) is autoimmune and it is present in genetically predisposed subjects, characterized by the intolerance to determined proteins present in wheat, rye and barley: called gluten and gliadin. It is known that there is an association between HLA-system and celiac disease (HLA-DQ2/HLA-DQ8), but there aren't Cuban studies on this association, thus we analyzed the behavior of DQB1*02 and DQB1*03 alleles by means of an observational and analytical study in 65 patients with a presumptive diagnosis of celiac disease to include its detection in the diagnostic scheme of this complex disease. There was found that subjects carriers of the DQB1*02 allele (OR: 2,26) were more susceptible to suffer this disease than those non-carriers, that the 60 percent of the supposed patients presenting with the celiac disease had the HLA-DQ2 allele and the 3 percent had the HLA-DQ8 allele. We conclude that the HLA-DQ2/HLA-DQ8 genotyping is very useful for the diagnosis of the celiac disease