This prospective, cross-sectional study assessed the diagnostic accuracy of the MiniDock MTB test using sputum swabs and tongue swabs in 1380 patients aged 12 years or older with presumptive pulmonary tuberculosis. The study was conducted at outpatient centers in India, Nigeria, the Philippines, South Africa, Uganda, Vietnam, and Zambia. The reference standard was sputum culture, and comparators included sputum-smear microscopy and Xpert MTB/RIF Ultra assay.
Among the 226 patients (16.4%) with culture-confirmed tuberculosis, the MiniDock MTB test with sputum swabs showed a sensitivity of 85.7% (95% CI, 80.4 to 90.0). With tongue swabs, sensitivity was 79.6% (95% CI, 73.8 to 84.7). Specificity exceeded 97.5% for both swab types. Compared with Xpert MTB/RIF Ultra, the MiniDock MTB sputum swab sensitivity was 2.8 percentage points lower (95% CI, -6.0 to 0.5), indicating noninferiority. The test outperformed smear microscopy by 24.3 percentage points (95% CI, 17.9 to 30.7) for sputum swabs and 18.3 percentage points (95% CI, 12.0 to 24.7) for tongue swabs.
Usability was rated favorably, with a median System Usability Scale score of 75 (interquartile range, 65 to 80). No adverse events related to the index test were reported. The study was funded by the National Institutes of Health and others.
These findings suggest that the MiniDock MTB test is a promising diagnostic tool for tuberculosis, particularly in resource-limited settings. However, as a single cross-sectional study, further validation in diverse populations and settings is warranted before widespread implementation.
View Original Abstract ↓
BACKGROUND: Improved diagnostic tools for tuberculosis that are suitable for use in peripheral health centers are essential for reducing the persistent gap between estimated and notified cases. The diagnostic accuracy and usability of the MiniDock MTB test for detecting pulmonary tuberculosis is unknown.
METHODS: We conducted a prospective, cross-sectional study at outpatient centers in India, Nigeria, the Philippines, South Africa, Uganda, Vietnam, and Zambia. Patients 12 years of age or older with presumptive pulmonary tuberculosis were enrolled between September 12, 2024, and March 31, 2025. Assessment with MiniDock MTB was performed with sputum swabs and tongue swabs. Diagnostic accuracy was evaluated against a sputum-culture-based reference and as compared with sputum-smear microscopy and Xpert MTB/RIF Ultra assay. Usability was assessed with a system usability scale and direct observation.
RESULTS: A total of 1380 participants were enrolled; 255 (18.5%) had human immunodeficiency virus infection and 226 (16.4%) had culture-confirmed tuberculosis. MiniDock MTB sensitivity was 85.7% (95% confidence interval [CI], 80.4 to 90.0) with sputum and 79.6% (95% CI, 73.8 to 84.7) with tongue swabs; specificity was greater than 97.5% for both. Results of sputum tests with MiniDock MTB closely matched those with Xpert MTB/RIF Ultra for sensitivity (difference, -2.8 percentage points; 95% CI, -6.0 to 0.5). MiniDock MTB had greater sensitivity than smear microscopy for tests of sputum (difference, 24.3 percentage points; 95% CI, 17.9 to 30.7) and tongue swabs (difference, 18.3 percentage points; 95% CI, 12.0 to 24.7). The test showed diagnostic accuracy that was consistent with World Health Organization (WHO) accuracy targets for near-point-of-care tuberculosis diagnostics (≥85% sensitivity for sputum and ≥75% for nonsputum and ≥98% specificity for both). The median score on the system usability scale (range, 0 to 100, with higher scores indicating better perceived usability) was 75 (interquartile range, 65 to 80), which indicated good usability. No adverse events related to the index test were reported.
CONCLUSIONS: MiniDock MTB met WHO targets for diagnostic accuracy and usability for tuberculosis detection across diverse clinical settings. (Funded by the National Institutes of Health and others; Rapid Research in Diagnostics Development for TB Network and Assessing Diagnostics at Point-of-Care for Tuberculosis ClinicalTrials.gov numbers, NCT04923958 and NCT05941052.).