Accuracy of giant African pouched rats for diagnosing tuberculosis: comparison with culture and Xpert (R) MTB/RIF

作者：Mulder C^*; Mgode G F; Ellis H; Valverde E; Beyene N; Cox C; Reid S E; van't Hoog A H; Edwards T L

来源：International Journal of Tuberculosis and Lung Disease, 2017, 21(11): 1127-+.

DOI：10.5588/ijtld.17.0139

• diagnostic
• olfactory detection
• Cricetomys ansorgei
• sensitivity
• specificity

SETTING: Enhanced tuberculosis (TB) case finding using detection rats in Tanzania.
OBJECTIVES : To assess the diagnostic accuracy of detection rats compared with culture and Xpert (R) MTB/RIF, and to compare enhanced case-finding algorithms using rats in smear-negative presumptive TB patients. DESIGN: A fully paired diagnostic accuracy study in which sputum of new adult presumptive TB patients in Tanzania was tested using smear microscopy, 11 detection rats, culture and Xpert.
RESULTS : Of 771 eligible participants, 345 (45%) were culture-positive for Mycobacterium tuberculosis, and 264 (34%) were human immunodeficiency virus (HIV) positive. The sensitivity of the detection rats was up to 75.1% (95% CI 70.1-79.5) when compared with culture, and up to 81.8% (95% CI 76.0-86.5) when compared with Xpert, which was statistically significantly higher than the sensitivity of smear microscopy. Corresponding specificity was 40.6% (95% CI 35.9-45.5) compared with culture. The accuracy of rat detection was independent of HIV status. Using rats for triage, followed by Xpert, would result in a statistically higher yield than rats followed by light-emitting diode fluorescence microscopy, whereas the number of false-positives would be significantly lower than when using Xpert alone.
CONCLUSION: Although detection rats did not meet the accuracy criteria as standalone diagnostic or triage testing for presumptive TB, they have additive value as a triage test for enhanced case finding among smear-negative TB patients if more advanced diagnostics are not available.

• 出版日期2017-11