Vaccines and Immunity Theme, Medical Research Council (MRC) Unit, The Gambia at the London School of Hygiene and Tropical Medicine, Banjul, The Gambia.
Department of Science and Technology National Research Foundation (DST-NRF) Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa.
Clin Infect Dis. 2022 Jul 6;74(12):2136-2141. doi: 10.1093/cid/ciab839.
The development of a fast and accurate, non-sputum-based point-of-care triage test for tuberculosis (TB) would have a major impact on combating the TB burden worldwide. A new fingerstick blood test has been developed by Cepheid (the Xpert MTB Host Response [MTB-HR] prototype), which generates a "TB score" based on messenger RNA (mRNA) expression of 3 genes. Here we describe the first prospective findings of the MTB-HR prototype.
Fingerstick blood from adults presenting with symptoms compatible with TB in South Africa, The Gambia, Uganda, and Vietnam was analyzed using the Cepheid GeneXpert MTB-HR prototype. Accuracy of the Xpert MTB-HR cartridge was determined in relation to GeneXpert Ultra results and a composite microbiological score (GeneXpert Ultra and liquid culture) with patients classified as having TB or other respiratory diseases (ORD).
When data from all sites (n = 75 TB, 120 ORD) were analyzed, the TB score discriminated between TB and ORD with an area under the curve (AUC) of 0.94 (95% confidence interval [CI], .91-.97), sensitivity of 87% (95% CI, 77-93%) and specificity of 94% (88-97%). When sensitivity was set at 90% for a triage test, specificity was 86% (95% CI, 75-97%). These results were not influenced by human immunodeficiency virus (HIV) status or geographical location. When evaluated against a composite microbiological score (n = 80 TB, 111 ORD), the TB score was able to discriminate between TB and ORD with an AUC of 0.88 (95% CI, .83-.94), 80% sensitivity (95% CI, 76-85%) and 94% specificity (95% CI, 91-96%).
Our interim data indicate the Cepheid MTB-HR cartridge reaches the minimal target product profile for a point of care triage test for TB using fingerstick blood, regardless of geographic area or HIV infection status.
开发一种快速、准确、非痰基的即时护理分诊测试结核病（TB）将对全球结核病负担产生重大影响。 Cepheid（Xpert MTB 宿主反应 [MTB-HR] 原型）开发了一种新的指尖血检测，该检测基于信使 RNA（mRNA）表达的 3 个基因生成“TB 评分”。 在这里，我们描述了 MTB-HR 原型的第一个前瞻性发现。
使用 Cepheid GeneXpert MTB-HR 原型分析来自南非、冈比亚、乌干达和越南出现与结核病相符症状的成年人的指尖血。 Xpert MTB-HR 试剂盒的准确性与 GeneXpert Ultra 结果以及复合微生物评分（GeneXpert Ultra 和液体培养）相关，将患者分类为结核病或其他呼吸道疾病（ORD）。
当分析所有地点的数据（n = 75 例结核病，120 例 ORD）时，TB 评分在区分结核病和 ORD 方面具有 0.94 的曲线下面积（95%置信区间 [CI]，0.91-0.97），灵敏度为 87%（95%CI，77-93%），特异性为 94%（88-97%）。 当分诊测试的灵敏度设定为 90%时，特异性为 86%（95%CI，75-97%）。 这些结果不受人类免疫缺陷病毒（HIV）状态或地理位置的影响。 当评估复合微生物评分（n = 80 例结核病，111 例 ORD）时，TB 评分能够区分结核病和 ORD，曲线下面积为 0.88（95%CI，0.83-0.94），灵敏度为 80%（95%CI，76-85%），特异性为 94%（95%CI，91-96%）。
我们的中间数据表明，无论地理位置或 HIV 感染状况如何，Cepheid MTB-HR 试剂盒都达到了使用指尖血进行即时护理分诊测试结核病的最低目标产品概况。
