Instituto de Investigaciones Biomédicas en Retrovirus y SIDA (INBIRS), Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina.
HIV Med. 2012 Oct;13(9):564-7. doi: 10.1111/j.1468-1293.2012.01011.x. Epub 2012 Mar 21.
In Argentina, HIV diagnosis in adults is made using one or two enzyme immunoassay tests and a confirmatory test. These strategies may fail to identify infected individuals during early primary infection, which represents an important public health problem among groups with a high HIV incidence, such as men who have sex with men (MSM) (6.3% persons/year). The general objective of this study was to contribute to reducing HIV transmission among MSM through the identification of antibody-negative, nucleic acid-positive individuals.
A total of 1549 MSM were recruited for an HIV seroprevalence study. A total of 161 (10.4%) MSM were HIV-positive and 14 (0.9%) were indeterminate. Among the 1374 negative individuals, 16 (1.2%) exhibited reactive results in the screening assay. Indeterminate Western blot (WB) samples and negative WB samples (with discordant results in the screening) were analysed to detect HIV nucleic acid by viral load testing. Up to 23.1% of HIV-indeterminate WB samples and 7.1% of HIV-negative WB samples with discordant results in the screening assays had detectable nucleic acid. Overall, 14.8% of the samples with discordant or indeterminate results were identified as HIV-positive using direct diagnosis. With the identification of four new cases using the nucleic acid detection test, the HIV prevalence in MSM increased by 0.3% (from 10.4 to 10.7%).
The results of this study suggest the importance of including nucleic acid detection in the HIV algorithm for MSM with HIV-indeterminate WB results and those with HIV-negative WB results and discordant results in screening assays, in order to decrease HIV transmission among this population with a high HIV prevalence and incidence.
在阿根廷，成年人的 HIV 诊断采用一种或两种酶免疫测定法和一种确认性检测。这些策略可能无法在早期原发性感染期间识别出感染者，这在 HIV 发病率较高的人群（例如男男性行为者 (MSM)，发生率为 6.3%/年）中是一个重要的公共卫生问题。本研究的总体目标是通过识别抗体阴性、核酸阳性的个体，减少 MSM 中的 HIV 传播。
共招募了 1549 名 MSM 进行 HIV 血清流行率研究。共有 161 名（10.4%）MSM 为 HIV 阳性，14 名（0.9%）为不确定。在 1374 名阴性个体中，16 名（1.2%）在筛查试验中表现出反应性结果。对不确定的 Western blot（WB）样本和筛查结果不一致的阴性 WB 样本（筛查结果不一致）进行分析，以通过病毒载量检测检测 HIV 核酸。多达 23.1%的 HIV 不确定 WB 样本和 7.1%的筛查结果不一致的 HIV 阴性 WB 样本有可检测的核酸。总体而言，14.8%的筛查结果不一致或不确定的样本通过直接诊断被确定为 HIV 阳性。通过核酸检测发现了 4 例新病例，使 MSM 中的 HIV 流行率增加了 0.3%（从 10.4%增加到 10.7%）。
本研究结果表明，对于 WB 结果不确定的 MSM 和 WB 结果阴性且筛查结果不一致的 MSM，在 HIV 算法中纳入核酸检测非常重要，以便减少 HIV 发病率高和发病率高的这一人群中的 HIV 传播。
