David Anura, Singh Lyndel, Peloakgosi-Shikwambani Keneilwe, Nsingwane Zanele, Molepo Violet, Cangelosi Gerard, da Silva Pedro, Stevens Wendy, Scott Lesley
Wits Diagnostics Innovation Hub, Health Sciences Research Office, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
Wits Diagnostics Innovation Hub, Health Sciences Research Office, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
Clin Microbiol Infect. 2025 Jun;31(6):1040-1045. doi: 10.1016/j.cmi.2025.01.029. Epub 2025 Jan 28.
Tongue swabs (TS) have shown potential for detecting Mycobacterium tuberculosis complex (MTBC) through downstream molecular testing. Analytical performance varies, depending on the processing protocol and the molecular test used. This study aimed to first investigate the ease of use of TS collection in addition to acceptability by individuals being assessed for tuberculosis and second to determine the performance of self-collected TS on the Xpert MTB/rifampicin (RIF) Ultra (Ultra) assay (Cepheid, Sunnyvale, CA, USA) for MTBC and RIF resistance detection.
The ease of use of TS collection and acceptability by study participants was assessed through completion of a survey questionnaire. Analytical performance of self-collected TS on the Ultra assay was determined by comparing results with a liquid culture reference result and with Ultra on sputum. Results were additionally stratified by HIV and smear status.
Of the 399 survey respondents, all were happy with the TS collection procedure with minimal discomfort reported. Data analysis was performed on 321 specimens. The sensitivity of the Ultra TS assay for MTBC detection was 78.1% (95% CI, 66.0-87.5%), whereas the specificity was 100% (95% CI, 98.6-100%). Test performance was better in individuals with a higher bacillary load, with some variability. On HIV-positive individuals, TS performance is ∼30% lower than that on sputum but also slightly better than smear microscopy, whereas the performance of TS among HIV-negative individuals is similar to sputum (93% vs. 97%). For RIF resistance profiling, the Ultra TS assay showed 41/41 (100%) concordance with phenotypic drug-susceptibility testing.
Although self-collected TS have lower sensitivity compared with sputum, their ease of use and high acceptability make them a valuable additional specimen type for molecular tuberculosis testing. Self-collection can reduce the burden on healthcare workers and increase access to testing, particularly for individuals who are too busy to visit healthcare facilities or fear stigma.
舌拭子（TS）已显示出通过下游分子检测来检测结核分枝杆菌复合群（MTBC）的潜力。分析性能因处理方案和所使用的分子检测方法而异。本研究旨在首先调查TS采集的易用性以及被评估为结核病的个体的可接受性，其次确定自我采集的TS在Xpert MTB/利福平（RIF）Ultra（Ultra）检测（美国加利福尼亚州桑尼维尔市赛沛公司）上用于MTBC和RIF耐药性检测的性能。
通过完成调查问卷来评估TS采集的易用性和研究参与者的可接受性。通过将自我采集的TS在Ultra检测上的结果与液体培养参考结果以及痰液在Ultra检测上的结果进行比较，来确定其分析性能。结果还按HIV和涂片状态进行分层。
在399名调查受访者中，所有人都对TS采集程序感到满意，报告的不适感最小。对321份标本进行了数据分析。Ultra TS检测对MTBC检测的敏感性为78.1%（95%CI，66.0 - 87.5%），而特异性为100%（95%CI，98.6 - 100%）。在细菌载量较高的个体中检测性能更好，存在一定变异性。在HIV阳性个体中，TS的性能比痰液低约30%，但也略优于涂片显微镜检查，而在HIV阴性个体中，TS的性能与痰液相似（93%对97%）。对于RIF耐药性分析，Ultra TS检测与表型药物敏感性检测显示出41/41（100%）的一致性。
尽管自我采集的TS与痰液相比敏感性较低，但其易用性和高可接受性使其成为分子结核病检测中有价值的额外标本类型。自我采集可以减轻医护人员的负担并增加检测机会，特别是对于那些太忙而无法前往医疗机构或担心受污名化的个体。
