Hanifa Yasmeen, Fielding Katherine L, Chihota Violet N, Adonis Lungiswa, Charalambous Salome, Foster Nicola, Karstaedt Alan, McCarthy Kerrigan, Nicol Mark P, Ndlovu Nontobeko T, Sinanovic Edina, Sahid Faieza, Stevens Wendy, Vassall Anna, Churchyard Gavin J, Grant Alison D
London School of Hygiene & Tropical Medicine, London, United Kingdom.
The Aurum Institute, Johannesburg, South Africa.
PLoS One. 2017 Aug 3;12(8):e0181519. doi: 10.1371/journal.pone.0181519. eCollection 2017.
The World Health Organization (WHO) recommendation for regular tuberculosis (TB) screening of HIV-positive individuals with Xpert MTB/RIF as the first diagnostic test has major resource implications.
To develop a diagnostic prediction model for TB, for symptomatic adults attending for routine HIV care, to prioritise TB investigation.
Cohort study exploring a TB testing algorithm.
HIV clinics, South Africa.
Representative sample of adult HIV clinic attendees; data from participants reporting ≥1 symptom on the WHO screening tool were split 50:50 to derive, then internally validate, a prediction model.
TB, defined as "confirmed" if Xpert MTB/RIF, line probe assay or M. tuberculosis culture were positive; and "clinical" if TB treatment started without microbiological confirmation, within six months of enrolment.
Overall, 79/2602 (3.0%) participants on ART fulfilled TB case definitions, compared to 65/906 (7.2%) pre-ART. Among 1133/3508 (32.3%) participants screening positive on the WHO tool, 1048 met inclusion criteria for this analysis: 52/515 (10.1%) in the derivation and 58/533 (10.9%) in the validation dataset had TB. Our final model comprised ART status (on ART > 3 months vs. pre-ART or ART < 3 months); body mass index (continuous); CD4 (continuous); number of WHO symptoms (1 vs. >1 symptom). We converted this to a clinical score, using clinically-relevant CD4 and BMI categories. A cut-off score of ≥3 identified those with TB with sensitivity and specificity of 91.8% and 34.3% respectively. If investigation was prioritised for individuals with score of ≥3, 68% (717/1048) symptomatic individuals would be tested, among whom the prevalence of TB would be 14.1% (101/717); 32% (331/1048) of tests would be avoided, but 3% (9/331) with TB would be missed amongst those not tested.
Our clinical score may help prioritise TB investigation among symptomatic individuals.
世界卫生组织（WHO）建议对HIV阳性个体进行常规结核病（TB）筛查，将Xpert MTB/RIF作为首要诊断检测方法，这对资源有重大影响。
为前来接受常规HIV治疗的有症状成年人开发一种结核病诊断预测模型，以确定结核病调查的优先顺序。
探索结核病检测算法的队列研究。
南非的HIV诊所。
成年HIV诊所就诊者的代表性样本；根据WHO筛查工具报告有≥1种症状的参与者的数据按50:50比例拆分，用于推导并随后进行内部验证一个预测模型。
结核病，若Xpert MTB/RIF、线性探针分析或结核分枝杆菌培养呈阳性则定义为“确诊”；若在入组后6个月内开始抗结核治疗且无微生物学确诊则定义为“临床诊断”。
总体而言，接受抗逆转录病毒治疗（ART）的2602名参与者中有79人（3.0%）符合结核病病例定义，而接受ART前的906名参与者中有65人（7.2%）符合。在WHO工具筛查呈阳性的1133/3508名（32.3%）参与者中，1048人符合本分析的纳入标准：推导数据集中52/515人（10.1%）以及验证数据集中58/533人（10.9%）患有结核病。我们的最终模型包括ART状态（接受ART超过3个月与接受ART前或接受ART不足3个月）；体重指数（连续变量）；CD4细胞计数（连续变量）；WHO症状数量（1种与>1种症状）。我们使用临床相关的CD4细胞计数和体重指数类别将其转换为临床评分。截断分数≥3可识别出患有结核病的个体，其敏感性和特异性分别为91.8%和34.3%。如果对评分≥3的个体优先进行调查，68%（717/1048）有症状的个体将接受检测，其中结核病患病率为14.1%（101/717）；可避免32%（331/1048）的检测，但未接受检测的个体中会有3%（9/331）的结核病患者被漏诊。
我们的临床评分可能有助于确定有症状个体中结核病调查的优先顺序。
