Reither Klaus, Jugheli Levan, Glass Tracy R, Sasamalo Mohamed, Mhimbira Francis A, Weetjens Bart J, Cox Christophe, Edwards Timothy L, Mulder Christiaan, Beyene Negussie W, Mahoney Amanda
Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland; Ifakara Health Institute, Bagamoyo, Tanzania.
Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland.
PLoS One. 2015 Oct 7;10(10):e0135877. doi: 10.1371/journal.pone.0135877. eCollection 2015.
This study established evidence about the diagnostic performance of trained giant African pouched rats for detecting Mycobacterium tuberculosis in sputum of well-characterised patients with presumptive tuberculosis (TB) in a high-burden setting.
The TB detection rats were evaluated using sputum samples of patients with presumptive TB enrolled in two prospective cohort studies in Bagamoyo, Tanzania. The patients were characterised by sputum smear microscopy and culture, including subsequent antigen or molecular confirmation of Mycobacterium tuberculosis, and by clinical data at enrolment and for at least 5-months of follow-up to determine the reference standard. Seven trained giant African pouched rats were used for the detection of TB in the sputum samples after shipment to the APOPO project in Morogoro, Tanzania.
Of 469 eligible patients, 109 (23.2%) were culture-positive for Mycobacterium tuberculosis and 128 (27.3%) were non-TB controls with sustained recovery after 5 months without anti-TB treatment. The HIV prevalence was 46%. The area under the receiver operating characteristic curve of the seven rats for the detection of culture-positive pulmonary tuberculosis was 0.72 (95% CI 0.66-0.78). An optimal threshold could be defined at ≥ 2 indications by rats in either sample with a corresponding sensitivity of 56.9% (95% CI 47.0-66.3), specificity of 80.5% (95% CI 72.5-86.9), positive and negative predictive value of 71.3% (95% CI 60.6-80.5) and 68.7% (95% CI 60.6-76.0), and an accuracy for TB diagnosis of 69.6%. The diagnostic performance was negatively influenced by low burden of bacilli, and independent of the HIV status.
Giant African pouched rats have potential for detection of tuberculosis in sputum samples. However, the diagnostic performance characteristics of TB detection rats do not currently meet the requirements for high-priority, rapid sputum-based TB diagnostics as defined by the World Health Organization.
本研究为训练有素的非洲巨囊鼠在高负担环境下检测确诊为肺结核(TB)的典型患者痰液中结核分枝杆菌的诊断性能提供了证据。
使用在坦桑尼亚巴加莫约进行的两项前瞻性队列研究中纳入的疑似肺结核患者的痰液样本,对用于检测结核病的大鼠进行评估。通过痰液涂片显微镜检查和培养对患者进行特征分析,包括随后对结核分枝杆菌的抗原或分子确认,并根据入组时及至少5个月随访期的临床数据确定参考标准。7只经过训练的非洲巨囊鼠在运往坦桑尼亚莫罗戈罗的APOPO项目后,用于检测痰液样本中的结核病。
在469名符合条件的患者中,109名(23.2%)结核分枝杆菌培养呈阳性,128名(27.3%)为非结核对照,在未接受抗结核治疗的情况下5个月后持续康复。艾滋病毒感染率为46%。7只大鼠检测培养阳性肺结核的受试者工作特征曲线下面积为0.72(95%CI 0.66 - 0.78)。可将最佳阈值定义为任一样本中大鼠指示≥2次,相应的灵敏度为56.9%(95%CI 47.0 - 66.3),特异性为80.5%(95%CI 72.5 - 86.9),阳性和阴性预测值分别为71.3%(95%CI 60.6 - 80.5)和68.7%(95%CI 60.6 - 76.0),结核病诊断准确率为69.6%。诊断性能受到杆菌载量低的负面影响,且与艾滋病毒感染状况无关。
非洲巨囊鼠有检测痰液样本中结核病的潜力。然而,目前用于检测结核病的大鼠的诊断性能特征不符合世界卫生组织定义的高优先级、基于痰液的快速结核病诊断要求。