Brumwell Amanda, Herrera Rosa, Contreras Kevin, Lee Mildred, Becerra Eduardo, Estrada-Guzmán Julia, Nicholson Tom, Machado Contreras Rene, Brooks Meredith B
Advance Access & Delivery, Durham, North Carolina, USA.
Department of Global Health, University of Washington, Seattle, Washington, USA.
BMJ Open. 2025 Sep 14;15(9):e097505. doi: 10.1136/bmjopen-2024-097505.
Despite low sensitivity and implementation challenges, the tuberculin skin test (TST) remains the standard-of-care tuberculosis (TB) infection test in Mexico. Interferon gamma release assays (IGRA) may overcome TST-related challenges. Within the confines of the local programmatic setting, this cross-sectional study evaluated the prevalence of TB infection (TBI) and concordance of TST and IGRA in three high-risk populations in Mexicali, Baja California, Mexico.
Household contacts (HHC) of individuals with TB, people who use drugs (PWUD), people deprived of liberty (PDL) and prison employees underwent evaluation for TBI using TST and QIAreach, a novel IGRA. Prevalence of infection, concordance of test results and reactivity trends of time-to-results (TTR) by TST-induration size were assessed.
In total, 214 of 411 (52.07%) people who had TST and 269 of 460 (58.48%) people who had IGRA tested positive for TBI. Frequency of infection varied across risk groups (HHC 29 (29.6%); PWUD 67 (70.53%); PDL 111 (56.06%) and prison employees 7 (35.0%), p<0.001). Overall concordance of TST and IGRA was 74.4%. Among people without a BCG vaccination, TTR decreased as TST induration size increased (from 1200 s in 0-4 mm to 808 s in >20 mm, p=0.05).
All risk groups had a high frequency of TBI, necessitating locally tailored guidelines for screening, treatment and management of TBI to optimise care for vulnerable populations.
尽管结核菌素皮肤试验（TST）敏感性较低且在实施过程中存在挑战，但它仍是墨西哥结核病（TB）感染检测的标准护理方法。干扰素γ释放试验（IGRA）可能会克服与TST相关的挑战。在当地项目环境范围内，这项横断面研究评估了墨西哥下加利福尼亚州墨西卡利三个高危人群中结核感染（TBI）的患病率以及TST和IGRA的一致性。
结核病患者的家庭接触者（HHC）、吸毒者（PWUD）、被剥夺自由者（PDL）和监狱工作人员接受了TST和一种新型IGRA（QIAreach）的TBI评估。评估了感染患病率、检测结果的一致性以及TST硬结大小的结果出现时间（TTR）的反应性趋势。
共有411名进行TST检测的人中的214人（52.07%）以及460名进行IGRA检测的人中的269人（58.48%）TBI检测呈阳性。感染频率在不同风险组中有所不同（HHC为29人（29.6%）；PWUD为67人（70.53%）；PDL为111人（56.06%）；监狱工作人员为7人（35.0%），p<0.001）。TST和IGRA的总体一致性为74.4%。在未接种卡介苗的人群中，TTR随着TST硬结大小的增加而降低（从0-4毫米时的1200秒降至>20毫米时的808秒，p=0.05）。
所有风险组的TBI频率都很高，因此需要针对TBI的筛查、治疗和管理制定因地制宜的指南，以优化对弱势群体的护理。
