Comparison of stool and gastric content samples analyzed with genexpert ultra for the diagnosis of pulmonary tuberculosis in children under five in Niger: a multi-center diagnostic study

BACKGROUND: Pediatric tuberculosis is challenging to diagnose due to the limited presence of bacteria and difficulties in obtaining high-quality sputum samples. This study assessed the effectiveness of stool samples versus gastric contents analyzed with GeneXpert Ultra for diagnosing pulmonary tuberculosis in children under five years old. METHODS: A diagnostic study was conducted in Niger over a one-year period (January 1 to December 31, 2024), at multiple centers. Socio-demographic data and GeneXpert Ultra results from stool and gastric samples were collected in accordance with STARD guidelines. Data analysis was performed using Excel 2020 and JAMOVI 2.3.28 software to calculate sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). RESULTS: This study included 401 patients with a median age of 18 months (interquartile range (IQR) 11-24 months) and a sex ratio of 1.37. The diagnostic performance of the test showed a sensitivity of 77.8% and a specificity of 99%, with an overall accuracy of 98.5%. The positive and negative predictive values were 63.6% and 99.5% respectively. CONCLUSION: GeneXpert stool testing is a valuable complementary approach to gastric content examination for detecting tuberculosis. Integrating it into screening strategies, especially in resource-limited settings, can enhance pediatric tuberculosis detection and management.