This updated Cochrane review assessed the diagnostic accuracy of Xpert Ultra for pulmonary tuberculosis and rifampicin resistance in children under 15 years of age. Across 14 studies involving over 25,000 participants, Xpert Ultra demonstrated high specificity (>94%) across sputum, gastric aspirate, stool, and nasopharyngeal samples, while sensitivity varied substantially by specimen type. Sensitivity was highest in sputum (75.3%), followed by gastric aspirate (70.4%) and stool (56.1%), and lowest in nasopharyngeal aspirates (43.7%). Evidence for tuberculous meningitis and lymph node tuberculosis was lacking, and rifampicin resistance detection—while showing high accuracy—was based on very limited data.
Trace-positive results, commonly observed in children, did not significantly reduce specificity, supporting Xpert Ultra’s reliability despite low DNA quantities. Sensitivity tended to be lower when compared with a composite reference standard, though specificity remained consistently high. Overall, findings support the use of Xpert Ultra as an initial rapid molecular diagnostic tool in children with presumed tuberculosis, while highlighting ongoing limitations in evidence quality, variability across settings, and scarce data for drug resistance detection.
Keywords: Xpert Ultra, pediatric tuberculosis, rapid molecular diagnostics, rifampicin resistance