Pediatric
pulmonary tuberculosis diagnosis is difficult because young children are unable to expectorate sputum samples. Testing stool for
tuberculosis DNA from swallowed sputum may diagnose
pulmonary tuberculosis. Hospitalized children with suspected
tuberculosis had stool, nasopharyngeal, and gastric aspirates cultured that confirmed
pulmonary tuberculosis in 16/236 patients. Twenty-eight stored stools from these 16 children were used to evaluate stool polymerase chain reaction (PCR) for
tuberculosis diagnosis compared with 28 stool samples from 23 healthy control children. Two
DNA extraction techniques were used: fast-
DNA mechanical homogenization and
Chelex-resin chemical extraction.
DNA was tested for
tuberculosis DNA with a hemi-nested IS6110 PCR. PCR after Fast-
DNA processing was positive for 6/16 culture-proven
tuberculosis patients versus 5/16 after
Chelex extraction (sensitivity 38% and 31%, respectively). All controls were negative (specificity 100%). If sensitivity can be increased, stool PCR would be a rapid, non-invasive, and relatively bio-secure initial test for children with suspected
pulmonary tuberculosis.