Dwenger L V, Funke N, Stephany P, Suarez I, Wiesmüller G A, Neuhann F
Gesundheitsamt der Stadt Köln, Abteilung Infektions- und Umwelthygiene, Tuberkulose-Beratungsstelle.
Institut für Arbeits-, Sozial- und Umweltmedizin, Universitätsklinik, RWTH Aachen.
Pneumologie. 2021 Aug;75(8):567-576. doi: 10.1055/a-1479-0168. Epub 2021 May 10.
As part of tuberculosis control and the WHO end-TB strategy, contact persons of tuberculosis patients in Germany are examined for a possible infection with latent tuberculosis (LTBI). Activation of LTBI contributes a considerable proportion of newly reported tuberculosis cases in low-incidence countries such as Germany. Therefore, the aim is to detect cases of LTBI and, through chemopreventive treatment of these cases, prevent future, post-primary, active tuberculosis.In Germany, the rate of LTBI among contact persons of people diagnosed with active tuberculosis is not systematically recorded. The aim of the present work was to close this data gap for Cologne, a major city in Germany with a TB incidence of around 9/100,000 in the past years. The study further aimed to describe risk factors for LTBI and to reevaluate the standard inclusion criteria for contact investigation for tuberculosis under routine conditions in Germany.
For the period 07/2012 to 12/2016, the retrospective cohort study examined the rate of LTBI diagnoses among contact persons of those with pulmonary tuberculosis notified at the Cologne public health department, as well as factors that increase the LTBI infection risk of contact persons. The diagnosis of latent tuberculosis was made when the interferon-gamma release assay (IGRA) was positive and there were no signs of active tuberculosis. The study included contact persons who cumulatively had a previously defined minimum total contact time with a tuberculosis patient, who were at least 5 years old at the time of the study and who were registered in Cologne. Statistical evaluation was carried out descriptively as absolute and relative frequency with a significance level of p ≤ 0.05. The analytical evaluation was carried out with univariate and multivariate logistic regression.
Of a total of 3862 IGRA examinations among contact persons, 2834 cases met the inclusion criteria. A median of seven contact persons per index patient was reported. 12.5 % of the study group tested positive for LTBI. In contact persons of microscopically open index patients, the positivity rate was 11.4 %, in culturally open but microscopically negative index patients, it was 14.3 %. Factors associated with a higher risk of LTBI included male sex (OR = 1.95), age ≥ 50 years (OR = 1.8) and household exposure (OR = 2.37).
Using the German standard criteria, the positivity rate of IGRA testing and the diagnosis of LTBI among contacts in the present study was 12.5 %, which is lower than in other similar studies. Factors identified in the cohort for an increased risk of LTBI confirm known constellations. The significantly higher positivity rate among contact persons of microscopically negative but culturally positive index patients (p = 0.033) underscores the need to conduct a detailed contact examination of individuals of this group as well.
作为结核病控制和世界卫生组织终止结核病战略的一部分，德国对结核病患者的接触者进行检查，以确定其是否可能感染潜伏性结核病（LTBI）。在德国等低发病率国家，LTBI的激活在新报告的结核病病例中占相当大的比例。因此，目标是检测LTBI病例，并通过对这些病例进行化学预防治疗，预防未来的原发性后活动性结核病。在德国，未系统记录确诊为活动性结核病患者的接触者中LTBI的发生率。本研究的目的是填补德国大城市科隆的这一数据空白，过去几年科隆的结核病发病率约为9/10万。该研究还旨在描述LTBI的危险因素，并重新评估德国常规条件下结核病接触者调查的标准纳入标准。
在2012年7月至2016年12月期间，这项回顾性队列研究调查了科隆公共卫生部门通报的肺结核患者接触者中LTBI诊断率，以及增加接触者LTBI感染风险的因素。当干扰素-γ释放试验（IGRA）呈阳性且无活动性结核病迹象时，诊断为潜伏性结核病。该研究纳入了累计与结核病患者有先前定义的最短总接触时间、研究时至少5岁且在科隆登记的接触者。统计评估采用绝对和相对频率进行描述性分析，显著性水平为p≤0.05。分析评估采用单变量和多变量逻辑回归。
在接触者的3862次IGRA检查中，2834例符合纳入标准。每位索引患者报告的接触者中位数为7人。研究组中12.5%的人LTBI检测呈阳性。在显微镜下开放性索引患者的接触者中，阳性率为11.4%，在培养阳性但显微镜下阴性的索引患者的接触者中，阳性率为14.3%。与LTBI风险较高相关的因素包括男性（OR=1.95）、年龄≥50岁（OR=1.8）和家庭接触（OR=2.37）。
采用德国标准标准，本研究中接触者IGRA检测的阳性率和LTBI诊断率为12.5%，低于其他类似研究。在队列中确定的增加LTBI风险的因素证实了已知情况。显微镜下阴性但培养阳性的索引患者的接触者中显著较高的阳性率（p=0.033）强调了对该组个体进行详细接触者检查的必要性。
