Clinical and radiologic factors associated with detection of Mycobacterium tuberculosis in children under 5 years old using invasive and noninvasive sample collection techniques - Kenya

Background Pediatric tuberculosis (TB) remains a critical public health concern, yet bacteriologic confirmation of TB in children is challenging. Clinical, demographic, and radiological factors associated with a positive Mycobacterium tuberculosis specimen in young children (≤5 years) are poorly understood. Methods We conducted a prospective cohort study of young children with presumptive TB and examined clinical, demographic, and radiologic factors associated with invasive and non-invasive specimen collection techniques (gastric aspirate, induced sputum, nasopharyngeal aspirate, stool, and string test); up to two samples were taken per child, per technique. We estimated associations between these factors and a positive specimen for each technique using generalized estimating equations (GEE) and logistic regression. Results A median of 544 (range: 507-566) samples were obtained for each specimen collection technique from 300 enrolled children; bacteriologic yield was low across all collection techniques (range 1-7% from Xpert MTB/RIF or culture), except for lymph node fine needle aspiration (29%) taken for children with cervical lymphadenopathy. Factors associated with positive M. tuberculosis samples across all techniques included: prolonged lethargy (median adjusted odds ratio (aOR): 8.1; range: 3.9-10.1), history of exposure with a TB case (median aOR: 6.1, range: 2.9-9.0), immunologic evidence of M. tuberculosis infection (median aOR: 4.6, range: 3.7-9.2), large airway compression (median aOR: 6.7, range: 4.7-9.5), and hilar/mediastinal density (median aOR: 2.9, range: 1.7-3.2). Conclusions Identifying factors that lead to a positive M. tuberculosis specimen in very young children can inform clinical management and increase the efficiency of diagnostic testing in children being assessed for TB.