Respiratory Specimens for the Diagnosis of Pediatric Pulmonary Tuberculosis: A Comparative Assessment

The objective was to assess the utility of induced sputum (IS) as an alternative or add-on to gastric lavage and aspirate (GLA) as the respiratory specimen to diagnose pulmonary tuberculosis (PTB) in children. After consent, fifty children aged 0–14 years with suspected PTB were enrolled. Sputum/induced sputum and gastric lavage from the participants were collected on two consecutive days. Bronchoalveolar lavage was also done if indicated. The microbiological isolation in these specimens by Smear, MGIT culture, or Xpert MTB/RIF assay was compared. Based on the clinical, radiological, and microbiological profile, 23/50 children were diagnosed with PTB. If GLA was used alone, the yield was 11 cases (47.8%). If sputum (expectorated or induced) was used alone, the yield was 12 cases (52.1%). The difference in the two yields was not statistically significant (p = 1). The combined yield of GA and sputa was 69.5%, which was significantly more than when either of the specimens was used alone. Sputum was induced in 11 children, who could not expectorate. GLA and IS were compared, as these are the typical specimens obtainable in children who cannot expectorate. The yield of GLA was 4/11(36.36%) in these samples, and it was 5/11 (45.45%) for IS. Combining GLA and IS increased the yield to 7/11(63.6%) which amounted to a 27.2% increase from using GLA alone. IS is a valuable tool to increase the microbiological yield for the diagnosis of PTB in young children who cannot expectorate and should be considered routinely.