Resistencia transmitida de VIH-1 en pacientes sin exposición a tratamiento antirretroviral: Guatemala / Transmitted HIV-1 resistance in patients without exposure to antiretroviral treatment: Guatemala / Resistência transmitida ao HIV-1 em pacientes sem exposição ao tratamento antirretroviral: Guatemala

El objetivo del estudio fue describir los niveles de resistencia transmitida de VIH-1 en adultos atendidos en Unidades de Atención Integral de Guatemala. El estudio incluyó registros de 185 pacientes adultos VIH-1 positivo, de reciente diagnóstico sin antecedente de uso de TAR, de noviembre del 2019 a noviembre del 2020. El análisis se realizó en el software DeepChek® v2.0, para la clasificación de la resistencia se siguió el algoritmo de Stanford HIVdb (v9.4 - 07/12/2022). Se encontró 18.4% (IC 95% 13.1 - 24.7%) de resistencia general a alguna familia de ARVs. Se evidenció 15.1% (IC 95% 10.3 - 21.1%) de resistencia individual a la familia de INNTR afectando principalmente a NVP y EFV; 2.2% (IC 95% 0.6 - 5.4%) de resistencia a INTR, mayormente a FTC/3TC; y 2.7% (IC 95% 0.9 - 6.2%) de resistencia intermedia y baja los IP NFV y LPV/r. Tres casos presentaron resistencia múltiple a los INTR + INNTR. Las mutaciones más frecuentemente encontradas fueron K103N (41.2%), M184V/I (8.8%) y M46I (5.9%). La elevada resistencia transmitida del VIH-1 en pacientes atendidos en distintas Unidades de Atención Integral del VIH, demuestra la importancia de analizar periódicamente la tendencia de la resistencia en personas que no han estado expuestas a ARVs, lo cual a su vez es un marcador indirecto de presencia de resistencia adquirida en el país, datos que evidencian la necesidad de acciones e intervenciones prontas y efectivas dado su impacto en la salud pública.

The objective of this study was to describe the levels of transmitted HIV-1 resistance in patients with a recent HIV diagnosis before starting ART, treated in Comprehensive Care Units in Guatemala during the years 2019 and 2020. The study included records of 185 HIV-positive adult patients, recently diagnosed with HIV without a history of ART use. The analysis was carried out in the DeepChek® v2.0 software, the Stanford HIVdb algorithm (v9.4 - 07/12/2022) was followed to classify resistance. 18.4% (95% CI 13.1 - 24.7%) of general resistance to some family of ARVs was found. There was evidence of 15.1% (95% CI 10.3 - 21.1%) of individual resistance to the NNRTI family, mainly affecting NVP and EFV; 2.2% (95% CI 0.6 - 5.4%) resistance to INTR, mostly to FTC/3TC; and 2.7% (95% CI 0.9 - 6.2%) of intermediate and low resistance IP NFV and LPV/r. Three cases presented multiple resistance to NRTIs + NNRTIs. The most frequently found mutations were K103N (41.2%), M184V/I (8.8%) and M46I (5.9%). The high transmitted resistance of HIV-1 in patients treated in different Comprehensive HIV Care Units demonstrates the importance of periodically analyzing the trend of resistance in people who have not been exposed to ARVs, which in turn is an indirect marker. of the presence of acquired resistance in the country, data that demonstrate the need for prompt and effective actions and interventions given its impact on public health.

O objetivo deste estudo foi descrever os níveis de resistência transmitida ao HIV-1 em adultos tratados em Unidades de Cuidados Integrais na Guatemala. O estudo incluiu prontuários de 185 pacientes adultos HIV-1 positivos, recentemente diagnosticados sem histórico de uso de TARV, no período de novembro de 2019 a novembro de 2020. A análise foi realizada no software DeepChek® v2.0, para classificação da resistência, O algoritmo Stanford HIVdb (v9.4 - 07/12/2022) foi seguido. Foi encontrada 18.4% (IC 95% 13.1 - 24.7%) de resistência geral a alguma família de ARVs. Houve evidência de 15.1% (IC 95% 10.3 - 21.1%) de resistência individual à família de NNRTI, afetando principalmente NVP e EFV; 2.2% (IC 95% 0.6 - 5.4%) resistência ao INTR, principalmente ao FTC/3TC; e 2.7% (IC 95% 0.9 - 6.2%) de resistência intermediária e baixa ao IP NFV e LPV/r. Três casos apresentaram resistência múltipla a NRTIs + NNRTIs. As mutações mais frequentemente encontradas foram K103N (41.2%), M184V/I (8.8%) e M46I (5.9%). A elevada resistência transmitida do HIV-1 em pacientes atendidos em diferentes Unidades de Cuidados Integrados ao HIV demonstra a importância de analisar periodicamente a tendência de resistência em pessoas que não foram expostas aos ARVs, o que por sua vez é um marcador indireto da presença de ARVs adquiridos. resistência no país, dados que demonstram a necessidade de ações e intervenções rápidas e eficazes dado o seu impacto na saúde pública.

Antiangiogenic VEGF165b expression in human breast MCF-7 and MCF-10A cells exposed to reverse transcriptase and protease inhibitors / Expresión de VEGF165b antiangiogénico en células MCF-7 y MCF-10A de mama humana expuesto a inhibidores de la transcriptasa inversa y la proteasa

The combined antiretroviral therapy (cART), a multidrug combination regimen, usually consisting Nucleoside Reverse Transcriptase Inhibitors, non- Nucleoside Reverse Transcriptase Inhibitors and Protease Inhibitors has altered the morbidity pattern affecting HIV-infected individuals to include non-AIDS-defining malignancies (nADMs). The speculation is rife; does cART induce or promote the progression of nADMs such as breast cancer? This study was therefore designed to investigate of the effects of some antiretroviral drugs (at clinically relevant concentrations) on the expression of anti-angiogenic gene; VEGF165b in two human breast cell lines; MCF-7 and MCF-10A by Real Time qPCR and immuno-fluorescence. All of the antiretroviral drugs and combinations tested produced patterns of slight up or downregulation of VEGF165b mRNA expression but the alterations did not attain statistical significance. They also did not alter VEGF165bprotein localisation in both cell lines. The findings reported here suggest that antiretroviral drugs probably do not influence the angiogenic pathway in the development of breast cancer in patients under the combined antiretroviral regimen.

El tratamiento antirretroviral combinado (TARc), un régimen de combinación de múltiples fármacos, consistiendo generalmente en inhibidores nucleósidos de la transcriptasa reversa, inhibidores no-nucleósidos de la transcriptasa reversa e inhibodres de proteasa que alteran el patrón de mortalidad que afecta a infectados por el VIH incluyendo neoplasias definidas como no HIV (nADMs). La especulación es moneda corriente; TARc induce o promueve la progresión de nADMs como cáncer de mama? Por lo tanto, este estudio se diseñó para investigar los efectos de algunos de los fármacos antirretrovirales (en concentraciones clínicamente relevantes) sobre la expresión del gen anti-angiogénico; VEGF165b en dos líneas celulares de mama humana; MCF-7 y MCF-10A por PCR tiempo real e inmunofluorescencia. Todos los fármacos antirretrovirales y las combinaciones probadas pueden regular en forma ligera hacia arriba o hacia abajo la expresión de ARNm producidos por VEGF165b pero las alteraciones no fueron estadísticamente significativos. Además, no se alteran los niveles de proteína VEGF165b, para la localización en ambas líneas celulares. Los resultados aquí presentados sugieren que los medicamentos antirretrovirales probablemente no influyen en la vía angiogénica en el desarrollo del cáncer de mama en pacientes bajo el régimen antirretroviral combinado.

Extensive variation in drug-resistance mutational profile of Brazilian patients failing antiretroviral therapy in five large Brazilian cities

Abstract Background Development of drug-resistance mutations is the main cause of failure in antiretroviral therapy. In Brazil, there is scarce information on resistance pattern for patients failing antiretroviral therapy. Objectives To define the HIV mutational profile associated with drug resistance in Brazilian patients from 5 large cities, after first, second or further failures to antiretroviral therapy. Methods We reviewed genotyping results of 1520 patients failing therapy in five Brazilian cities. Frequency of mutations, mean number of active drugs, viral susceptibility to each antiretrovirals drug, and regional differences were assessed. Results Mean time of antiretrovirals use was 22.7 ± 41.1 months. Mean pre-genotyping viral load was 4.2 ± 0.8 log (2.1 ± 2.0 after switching antiretrovirals). Mean number of remaining active drugs was 9.4, 9.0, and 7.9 after 1st, 2nd, and 3rd failure, respectively. We detected regional variations in drug susceptibility: while BA and RS showed the highest (∼40%) resistance level to ATV/r, FPV/r and LPV/r, in the remaining cities it was around half of this rate. We detected 90% efavirenz/nevirapine resistance in SP, only 45% in RS, and levels between 25% and 30% in the other cities. Regarding NRTI, we found a similar pattern, with RJ presenting the highest, and CE the lowest susceptibility rates for all NRTI. Zidovudine resistance was detected in only 3% of patients in RJ, against 45–65% in the other cities. RJ and RS showed 3% resistance to tenofovir, while in CE it reached 55%. DRV/r (89–97%) and etravirine (61–85%) were the most active drugs, but again, with a wide variation across cities. Conclusions The resistance mutational profile of Brazilian patients failing antiretroviral therapy is quite variable, depending on the city where patients were tested. This variation likely reflects distinctive choice of antiretrovirals drugs to initiate therapy, adherence to specific drugs, or circulating HIV-1 strains. Overall, etravirine and DRV/r remain as the most active drugs.

Computational drug design strategies applied to the modelling of human immunodeficiency virus-1 reverse transcriptase inhibitors

Reverse transcriptase (RT) is a multifunctional enzyme in the human immunodeficiency virus (HIV)-1 life cycle and represents a primary target for drug discovery efforts against HIV-1 infection. Two classes of RT inhibitors, the nucleoside RT inhibitors (NRTIs) and the nonnucleoside transcriptase inhibitors are prominently used in the highly active antiretroviral therapy in combination with other anti-HIV drugs. However, the rapid emergence of drug-resistant viral strains has limited the successful rate of the anti-HIV agents. Computational methods are a significant part of the drug design process and indispensable to study drug resistance. In this review, recent advances in computer-aided drug design for the rational design of new compounds against HIV-1 RT using methods such as molecular docking, molecular dynamics, free energy calculations, quantitative structure-activity relationships, pharmacophore modelling and absorption, distribution, metabolism, excretion and toxicity prediction are discussed. Successful applications of these methodologies are also highlighted.

Implementación del estudio farmacogenético de hipersensibilidad al abacavir HLA-B*5701 en Argentina / Implementation of pharmacogenetic study HLA-B*5701 to predict abacavir hipersensitivity in Argentina

El abacavir (ABC) es un antirretroviral inhibidor de la transcriptasa reversa del virus HIV-1 que está fuertemente asociado al desarrollo de reacciones de hipersensibilidad en individuos portadores del alelo HLA-B*5701. Objetivos: determinar la prevalencia del alelo HLA-B*5701 en pacientes HIV-1 positivos y en una población control de Argentina. Materiales y métodos: desde enero de 2012 hasta octubre de 2013 se estudiaron 869 pacientes HIV-1 positivos y 63 individuos no infectados con HIV-1. La detección del alelo HLA-B*5701 se realizó mediante un ensayo in house basado en la técnica de PCR en tiempo real, diseñado en nuestro laboratorio y validado según guías internacionales. Resultados: el primero de enero se implementó el estudio farmacogenético para la detección de hipersensibilidad al ABC en los pacientes incluidos en el Programa VIH/sida de la Dirección de SIDA y ETS, y en los niños infectados con HIV-1 del Hospital Garrahan. Para ello se adoptó un protocolo de envío, recepción y procesado de las muestras, con un informe detallado de los resultados. El alelo HLA-B*5701 se detectó en 42 individuos infectados con HIV-1 y en 3 individuos no infectados. Conclusiones: la prevalencia del alejo HLA-B*5701 en la población de pacientes infectados con HIV-1 y la población control fue la misma (4,8%), lo cual sugiere que la presencia de este alelo no influye en la infección por HIV-1. Esta prevalencia fue similar a la reportada para otras poblaciones de origen caucásico...

Prevalence and patterns of HIV transmitted drug resistance in Guatemala / Prevalencia y patrones de farmacorresistencia transmitida del VIH en Guatemala

Objective. To assess human immunodeficiency virus (HIV) diversity and the prevalence of transmitted drug resistance (TDR) in Guatemala. Methods. One hundred forty-five antiretroviral treatment-naïve patients referred to the Roosevelt Hospital in Guatemala City were enrolled from October 2010 to March 2011. Plasma HIV pol sequences were obtained and TDR was assessed with the Stanford algorithm and the World Health Organization (WHO) TDR surveillance mutation list. Results. HIV subtype B was highly prevalent in Guatemala (96.6%, 140/145), and a 2.8% (4/145) prevalence of BF1 recombinants and 0.7% (1/145) prevalence of subtype C viruses were found. TDR prevalence for the study period was 8.3% (12/145) with the Stanford database algorithm (score > 15) and the WHO TDR surveillance mutation list. Most TDR cases were associated with non-nucleoside reverse transcriptase inhibitors (NNRTIs) (83.3%, 10/12); a low prevalence of nucleoside reverse transcriptase inhibitors and protease inhibitors was observed in the cohort (< 1% for both families). Low selection of antiretroviral drug resistance mutations was found, except for NNRTI-associated mutations. Major NNRTI mutations such as K101E, K103N, and E138K showed higher frequencies than expected in ART-naïve populations. Higher literacy was associated with a greater risk of TDR (odds ratio 4.14, P = 0.0264). Conclusions. This study represents one of the first efforts to describe HIV diversity and TDR prevalence and trends in Guatemala. TDR prevalence in Guatemala was at the intermediate level. Most TDR cases were associated with NNRTIs. Further and continuous TDR surveillance is necessary to gain more in-depth knowledge about TDR spread and trends in Guatemala and to optimize treatment outcomes in the country.

Objetivo. Evaluar la diversidad del virus de la inmunodeficiencia humana (VIH) y la prevalencia de la farmacorresistencia transmitida en Guatemala. Métodos. Entre octubre del 2010 y marzo del 2011 se incluyeron en el estudio 145 pacientes no tratados anteriormente con antirretrovirales, derivados al Hospital Roosevelt en la Ciudad de Guatemala. Se obtuvieron las secuencias pol a partir del VIH plasmático y se evaluó la farmacorresistencia transmitida con el algoritmo de Stanford y la lista de mutaciones para la vigilancia de la farmacorresistencia transmitida de la Organización Mundial de la Salud (OMS). Resultados. El subtipo B del VIH fue sumamente prevalente en Guatemala (96,6%, 140/145), y se encontró una prevalencia de formas recombinantes BF1 de 2,8% (4/145) y una prevalencia del subtipo C del virus de 0,7% (1/145). La prevalencia de la farmacorresistencia transmitida durante el período de estudio fue de 8,3% (12/145) según el algoritmo de la base de datos de Stanford (puntuación > 15) y la lista de mutaciones para la vigilancia de la farmacorresistencia transmitida de la OMS. En la mayoría de los casos, la farmacorresistencia transmitida se asoció con los inhibidores de la transcriptasa inversa no análogos de nucleósidos (ITINN) (83,3%, 10/12); en la cohorte se observó una baja prevalencia asociada con los inhibidores de la transcriptasa inversa análogos de nucleósidos y con los inhibidores de la proteasa (< 1% para ambas familias de fármacos). Se encontró una baja selección de mutaciones causantes de farmacorresistencia debidas a los antirretrovirales, excepto en las mutaciones asociadas a los ITINN. Las mutaciones importantes relacionadas con los ITINN, como K101E, K103N y E138K, mostraron frecuencias más elevadas que las esperadas en las poblaciones vírgenes de tratamiento antirretroviral. En las personas con un nivel de escolaridad más elevado se encontró un mayor riesgo de farmacorresistencia transmitida (razón de posibilidades 4,14; P = 0,0264). Conclusiones. Este estudio representa uno de los primeros intentos de describir la diversidad del VIH, y la prevalencia de la farmacorresistencia transmitida y sus tendencias en Guatemala. La prevalencia de la farmacorresistencia transmitida en Guatemala presentó un nivel intermedio y en la mayoría de los casos se asoció con los ITINN. Se necesita una vigilancia más intensa y sostenida de la farmacorresistencia transmitida para conocer más exhaustivamente su grado de diseminación y sus tendencias en Guatemala, al igual que para optimizar los resultados del tratamiento antirretroviral en el país.

HIV transmitted drug resistance in adult and pediatric populations in Panama / Farmacorresistencia transmitida del VIH en poblaciones adultas y pediátricas en Panamá

Objetivo. Investigar la prevalencia de farmacorresistencia transmitida del VIH en adultos en Panamá mediante un estudio del umbral modificado de la Organización Mundial de la Salud (OMS) e investigar las tasas de resistencia inicial en lactantesseropositivos para el VIH en Panamá.Métodos. En el Instituto Conmemorativo Gorgas, en 47 adultos seropositivos al VIH se efectuó la genotipificación de las mutaciones asociadas con la farmacorresistencia transmitida en los genes de la transcriptasa inversa y la proteasa del VIH-1, según las directrices del estudio umbral de la OMS, modificadas para incluir a las personas ≤ 26 años de edad. Las tasas de prevalencia de las mutaciones farmacorresistentes contra tres clases de fármacos antirretroviral —inhibidores de la transcriptasa inversaanálogos de nucleósidos, inhibidores de la transcriptasa inversa no análogos de nucleósidos e inhibidores de la proteasa— se clasificaron en bajas (< 5,0%), moderadas (5,0%–15,0%) o altas (> 15,0%). También se llevó a cabo genotipificación y se calcularonlas tasas de prevalencia de las mutaciones causantes de farmacorresistencia en 25 lactantes.Resultados. En los adultos de Panamá la farmacorresistencia transmitida fue moderada: 6 de 47 adultos seropositivos para el VIH presentaron una o más mutacionesasociadas con farmacorresistencia transmitida. Las mutaciones farmacorresitentes de transmisión horizontal fueron moderadas para los inhibidores de la transcriptasainversa análogos de nucleósidos y los inhibidores de la transcriptasa inversa no análogos de nucleósidos, y bajas para los inhibidores de la proteasa. En Panamá la transmisiónvertical del VIH ha disminuido en el período 2002–2007, pero la prevalenciade la farmacorresistencia del VIH transmitida por vía vertical es moderada (12,0%) y está surgiendo como un problema debido a la cobertura antirretroviral incompletadurante el embarazo...

Objective. To investigate the prevalence of transmitted drug-resistant HIV among adults in Panama by using a modified World Health Organization Threshold Survey (WHO-TS) and to investigate rates of initial resistance among HIV-positive infants in Panama.Methods. At the Gorgas Memorial Institute, 47 HIV-positive adults were genotyped for mutations associated with transmitted drug resistance (TDR) in the reverse transcriptase andprotease genes of HIV-1, according to WHO-TS guidelines, modified to include patients ≤ 26 years old. Prevalence rates for drug-resistance mutations against three classes of antiretroviraldrugs—nucleoside analog reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), and protease inhibitors—were calculated as low (< 5.0%), moderate (5.0%–15.0%), and high (> 15.0%). Twenty-five infant patients were also genotyped and prevalence rates for drug-resistance mutations were calculated. Results. TDR among Panamanian adults was moderate: 6 of 47 HIV-positive adultsshowed one or more mutations associated with TDR. Horizontal TDR mutations were moderate for NRTIs and NNRTIs and low for protease inhibitors. Vertical transmission of HIV inPanama has decreased for 2002–2007, but vertical HIV TDR prevalence is moderate (12.0%) and is emerging as a problem due to incomplete antiretroviral coverage in pregnancy. Conclusions. The prevalence of HIV TDR indicated by this study, combined with knownrates of HIV infection in Panama, suggests more extensive surveys are needed to identify risk factors associated with transmission of HIV drug resistance. Specific WHO-TS guidelines for monitoring vertical transmission of drug-resistant HIV should be established.

Isolation of a laccase with HIV-1 reverse transcriptase inhibitory activity from fresh fruiting bodies of the Lentinus edodes (Shiitake mushroom).

A laccase with a molecular mass of 67 kDa and inhibitory activity toward HIV-1 reverse transcriptase (IC50 = 7.5 M) was isolated from fresh fruiting bodies of the Lentinus edodes (Shiitake mushroom). Its characteristics were compared with those of laccases from cultured mushroom mycelia reported earlier. The laccase was unadsorbed on DEAE-cellulose, Affi-gel blue gel and CM-cellulose, but was adsorbed on Con A-Sepharose. About 50-fold purification was achieved with a 19.2% yield of the enzyme. The activity of the enzyme increased steadily from 20°C to 70°C. The activity disappeared after exposure to the boiling temperature for 10 min. Its optimal pH was 4 and very little enzyme activity remained at and above pH 10. The laccase inhibited HIV-1 reverse transcriptase with an IC50 of 7.5 M, but did not demonstrate any antifungal or anti-proliferative activity.

Evaluation of adefovir & lamivudine in chronic hepatitis B: correlation with HBV viral kinetic, hepatic-necro inflammation & fibrosis.

Background & objectives: Chronic hepatitis B is an important cause of morbidity and mortality. We conducted a study comparing the efficacy of adefovir and lamivudine with respect to their impact on serum and hepatic viral DNA clearance, and improvement in hepatic necro-inflammatory score, in naive patients of chronic hepatitis B. Methods: This prospective randomized pilot study was conducted in Lok Nayak Hospital, New Delhi, involving 30 patients of chronic hepatitis B (both e antigen positive and negative); 15 were randomly selected to receive either adefovir or lamivudine for a period of 6 months. Quantification of serum and hepatic HBV DNA levels was done by real time PCR and liver biopsy was done at the beginning and end of 6 months. Results: Serum ALT was elevated to 2 or more times normalized in both the groups. In the adefovir group, two patients became HBeAg negative. In the lamivudine group, one patient became HBeAg negative. After therapy HBV DNA was negative in 26.7 per cent patients from adefovir group and 13.3 per cent patients from lamivudine group. Serum HBV DNA levels were correlated with the hepatic levels before therapy (r=0.843; P<0.001) and after therapy (r=0.713, P<0.001) showing strong correlation. There was a median reduction of 1.92 and 2.06 log copies per ml in serum HBV DNA load after adefovir and lamivudine therapy, respectively. The mean reduction in the histotogy activity index (HAI) score was 2 and 1.53, fibrosis score was 2.33 and 3.06 after adefovir and lamivudine therapy respectively. Interpretation & conclusions: Adefovir and lamivudine treatment caused biochemical and serological improvement when administered for about 6 months with significant reduction in HBV DNA, serum and hepatic viral load without completely clearing the virus from either serum or liver. It also helped in reduction of the necro-inflammatory and fibrosis score of patients with chronic hepatitis B. Our study also showed significant correlation between serum and hepatic HBV DNA levels both before and after therapy. There was not enough evidence to show therapeutic advantage of one drug over the other in any of the parameters measured.

High rate of mutation K103N causing resistance to nevirapine in Indian children with acquired immunodeficiency syndrome.

In north India the number of paediatric cases with acquired immunodeficiency syndrome (AIDS) is on the rise. Most drug combinations used for treatment of AIDS incorporate nevirapine, resistance to which develops very fast if given singly or because of unplanned interruptions. This paper investigates presence of mutations at codon 103 and codon 215 of the HIV pol gene causing resistance to nevirapine and zidovudine (AZT) respectively in 25 children with AIDS. Mutations T215Y and K103N were detected by a nested cum amplification refractory mutation system polymerase chain reaction (ARMS PCR) and the results were confirmed by direct sequencing in five randomly selected cases. Nineteen patients had received nevirapine containing regimen and six were drug naive. Mutation K103N was observed in 56% (14/25) of the children while mutation T215Y was found in none. Two of the six drug naïve children also showed K103N mutation. Thus, Indian children drug naïve or treated with nevirapine containing regimens show a high rate of mutation conferring resistance to nevirapine which calls for a judicious use of nevirapine both in antenatal and postnatal setting.

HIV-1 drug resistance among untreated patients in India: Current status.

HAART has dramatically improved survival and quality of life among people living with HIV and AIDS globally. However, drug resistant mutations of HIV are a great challenge to the benefits of HAART. Antiviral resistance can be mediated either by changes in the molecular target of therapy (the primary mechanism observed in HIV-1) or in other viral proteins that indirectly interfere with a drug's activity. Drug resistant mutations easily evolve in the presence of sub-optimal adherence. With the introduction of generic HAART, there has been a steep increase in the number of patients put on HAART in India. It should also be noted that since most patients pay for medications out of their own pockets, interruptions in therapy due to monetary constraints are not uncommon. There is little information on HIV drug resistance in resource constrained settings like India where the predominant circulating HIV-1 sub-type is C. The transmissibility of drug-resistant forms of the virus is also a major concern especially when formulating treatment guidelines. This article reviews published data available on the patterns of HIV-1 drug resistance among treatment naïve in India.

Incidence of lamivudine resistance associated mutations in pol-gene of HIV-1 in patients from north India: a preliminary report.

Screening of drug-resistant variants is very important for the effective clinical management of HIV-infected patients and development of new strategies. The present study was aimed to detect codon-184 mutations in the pol-gene of HIV leading to resistance to lamivudine (3-TC) by nested cum ARMS-PCR approach in 10 treated and 9 treatment naive patients. For correlation the whole blood CD4/CD8 cell counts and the soluble TNFRII levels in plasma were also determined. Of the 19 patients tested, mutant variants were observed in 2 patients (Met Val in one and Met Val & lle in second) both being treated with 3-TC. No mutations were detected in the treatment-naive patients. The results confirmed that, drug resistant variants of codon-184 emerge rapidly in patients receiving 3-TC containing regimens including our population, which is mainly infected with subtypeC of the virus that could be detected along with wild viral population using sensitive approaches such as ARMS-PCR.

Obstacles to successful antiretroviral treatment of HIV-1 infection: problems & perspectives.

Mutations in human immunodeficiency virus type 1 (HIV-1) are a major impediment to successful highly active antiretroviral therapy (HAART) and the design of anti-HIV vaccines. Although HAART has made long-term suppression of HIV a reality, drug resistance, drug toxicity, drug penetration, adherence to therapy, low levels of continued viral replication in cellular reservoirs and augmentation of host immune responses are some of the most important challenges that remain to be sorted out. Continuing viral replication in the face of HAART leads to the accumulation of drug resistance mutations, increase in viral loads and eventual disease progression. Patients who fail therapy have minimal options for their clinical management. Therefore, a clear understanding of the pathogenesis of drug-resistant HIV-1, and all of the issues that influence the success of HAART is urgently needed. In the present article, we discuss various obstacles to HIV therapy, and provide perspectives relating to these issues that are critical in determining the success or failure of HAART.

Diagnosis, antiretroviral therapy, and emergence of resistance to antiretroviral agents in HIV-2 infection: a review

Human immunodeficiency virus type 1 (HIV-1) and type 2 (HIV-2) are the causative agents of AIDS. HIV-2 is prevalent at moderate to high rates in West African countries, such as Senegal, Guinea, Gambia, and Cape Verde. Diagnosis of HIV-2 is made with a positive HIV-1/HIV-2 ELISA or simple/rapid assay, followed by one or two confirmatory tests specific for HIV-2. Following CD4+ T cell counts, HIV-2 viral burden and clinical signs and symptoms of immunodeficiency are beneficial in monitoring HIV-2 disease progression. Although non-nucleoside reverse transcriptase inhibitors are ineffective in treating HIV-2, nucleoside reverse transcriptase inhibitors and protease inhibitors can be effective in dual and triple antiretroviral regimens. Their use can decrease HIV-2 viral load, increase CD4+ T cell counts and improve AIDS-related symptoms. HIV-2 resistance to various nucleoside reverse transcriptase inhibitors and protease inhibitors, including zidovudine, lamivudine, ritonavir and indinavir, has been identified in some HIV-2 infected patients on antiretroviral therapy. The knowledge of HIV-2 peculiarities, when compared to HIV-1, is crucial to helping diagnose and guide the clinician in the choice of the initial antiretroviral regimen and for monitoring therapy success

Impacto de la terapia anti retroviral en la mortalidad de pacientes VIH+ chilenos: estudio caso control MORTAR / Impact of antiretroviral therapy in mortality of chilean HIV+ patients: a case control study

Background: Combined antiretroviral therapy (AVR) has shown a protective effect (PE) on morbidity and survival in HIV (+) patients of industrialised countries where triple-drug therapy (ARV-3) is standard. In Chile the public health system began providing double-drug therapy in 1997 (ARV-2) with 2 reverse transcriptase inhibitors. Aim: To assess the impact of ARV in morbimortality of HIV (+) patients in Chile after a year of follow up. Patients and methods: Retrospective case-control (1:1) study. Cases were 97 patients followed during 1997 for 6 or more months and dying during that period. Each case had a control of the same gender and CDC stage, similar age and CD4 count, but surviving a same period of follow up. A comparison of ARV before and during follow up (rate and type) was done. P carinii prophylaxis, pneumococcal immunization at baseline or follow up, frequency of hospital admissions and occurrence of opportunistic infections in both groups were assessed. Odds ratio (OR) for mortality, hospitalisation and opportunistic infections in ARV user, as well as treatment PE were calculated. Results: Twenty four (24.7 percent) cases and sixty six (68 percent) controls received ARV during follow up (p< 0.001), OR was 0.15 (CI 95 percent 0.08-0.3), p < 0.001, the PE was 6.6 for ARV users versus non users, among cases 19 patients received ARV-2 and five received ARV-3. Among controls, 41 patients received ARV-2 and 25 received ARV-3. These differences established an OR of 0.20 (CI 95 percent 0.09-0.04) and a PE of 5 for ARV-2 versus no ARV. For ARV-3 compared with no ARV the OR was 0.08 (CI 95 percent 0.003-0.26), and the PE 12.5. Fifty three (54.6 percent) cases and 13 (13.4 percent) controls required hospital admission, OR 0.49 (CI 95 percent 0.25-0.94), p=0.03, and PE of 2.04 of ARV versus no ARV; 82 (85.3 percent) cases and 50 (51 percent) controls had opportunistic infections, OR 0.5 (CI 95 percent 0.26-0.96), p=0.03 and PE of 2 for ARV versus no ARV. There were no significant differences in prior ARV, prophylaxis and immunisation between cases and controls. Conclusions: This study showed the high impact of ARV in short term morbimortality of HIV(+) patients and the need to implement antiretroviral therapy to all patients as an official health policy. This study did not answer the question of the role, if any, of weaker-than standard antiretroviral therapy

Alcances y limitaciones de los inhibidores no nucleósidos de la transcriptasa inversa del HIV: una revisión / Scopes and limitations of nonnucleoside inhibitors of the reversed transcriptase of HIV: revission

Los inhibidores no nucleósidos de la transcriptasa inversa (INTI) son drogas potentes para el tratamiento de la infección por el virus de la inmunodeficiencia humana (HIV). Los compuestos aprobados por la FDA hasta la fecha son Nevirapina (NVP), Delavirdina (DLV) y Efavirenz (EFV). Múltiples estudios demostraron la eficacia de estas drogas para reducir la carga viral (CV) y aumentar el recuento de linfocito CD4+(RCD4), pero ninguno demostró todavía beneficio clínico. Las principales ventajas de su uso son la simple posología y buena tolerancia. Los efectos adversos más importante son el rash, de características e intensidad variables y las alteraciones neurológicas producidas por EFV. Algunas limitaciones que presentan son la interacción farmacológicas con las rifamicinas (que limitan las opciones para las pacientes coinfectados con Mycobacterium Tuberculosis) y el rápido desarrollo de resistencia por parte del HIV a todas las drogas del grupo. La indicación del tratamiento antirretroviral a un paciente infectado con el virus de la inmunodeficiencias humana (HIV) es un momento único y complejo para el paciente y para el médico. El primero pone su esperanza en el tratamiento, mientras que el médico, debe evaluar muchos aspectos además de la efectividad potencial del esquema a indicar. En la práctica médica diaria, el paciente juega un rol fundamental en la elección del esquema farmacológico pues introduce un elemento no siempre considerado por el médico: es él quien tendrá que tomar los fármacos, quien se beneficiará de los resultados biológicos pero también quien deberá afrontar los efectos adversos (EA). Teniendo en cuenta lo anteriormente dicho, los INNTI debieran ser consideradas como tratamiento de primera linea para los pacientes infectados con HIV

Biología molecular del virus de la inmunodeficiencia humana y los recientes progresos en el tratamiento del SIDA / Molecular biology of HIV and recent progress in the treatment of AIDS

El virus de inmunodeficiencia humana (VIH), causante del síndrome de inmunodeficiencia adquirida (SIDA), ha constituido desde su emergencia hace 2 décadas, un enorme desafío a la investigación biomédica. Utilizando una amplia gama de recursos para interferir y evadir la respuesta inmune normal, infecta las células CD4+, ingresa a ellas a través de sus receptores de superficie, y expresa una alta frecuencia de mutación lo que le permite cambiar repetidamente sus determinantes antígenos. Los VIH tipo 1 y 2 corresponden a lentivirus, los cuales, junto a los oncornavirus y espumavirus integran la familia de retrovirus RNA humanos. En este artíulo se revisan los conocimientos actuales de la biología molecular del virus, se comentan modernas técnicas de diagnóstico como la reacción de transcriptasa reversa y polimerasa en cadena, usadas actualmente para medir la replicación del virus en la sangre del huésped infectado, y se discuten las actuales líneas de tratamiento exploradas, las que básicamente se dirigen a blancos moleculares susceptibles de intervención farmacológica que no afecten la funcionalidad celular, como son la interacción virus-receptor celular, , transcripción reversa del RNA viral, integración del provirus, procesamiento proteolítico del precursor gag-pol, y la regulación transcripcional virus específica por los productos tat y rev. Finalmente se comentan aspectos relacionados a la investigación en el campo de la inmunización VIH, desafío pendiente para la primera década de este nuevo siglo