OBJECTIVETo study the values of a combination of multiple less invasive or non-invasive examinations including chest computed tomography (CT) scan, purified protein derivative (PPD) test, erythrocyte sedimentation rate (ESR) test, and C-reactive protein (CRP) test in the diagnosis of pediatric sputum-negative pulmonary tuberculosis (TB).

METHODSA retrospective analysis was performed on the clinical data of 269 children with confirmed pulmonary TB. Clinical symptoms and test results were analyzed and compared between the sputum-negative group (161 patients) and the sputum-positive group (108 patients).

RESULTSThe sputum-negative group had atypical clinical symptoms, with fewer typical or relatively specific imaging features compared with the sputum-positive group. The positive rates of PPD, ESR, and CRP tests for the sputum-negative group were 39.1%, 44.1%, and 56.5%, respectively, versus 55.6%, 79.6%, and 59.3% for the sputum-positive group. There were significant differences in the positive rates of PPD and ESR tests between the two groups (P<0.05). More than 80% of the patients in each group were diagnosed with pulmonary TB according to three or four less invasive or non-invasive tests, without significant difference in the positive rate between the two groups (P>0.05). Forty-six patients in the sputum-negative group underwent bronchoscopy, and morphological changes with a diagnostic value and/or etiological and pathological evidence were observed in 40 (87.0%) of them.

CONCLUSIONSThe diagnosis rate of pediatric sputum-negative pulmonary TB can be increased by combining tests including chest CT scan, PPD test, ESR test, and CRP test. Bronchoscopy is a reliable method for the auxiliary diagnosis of pediatric sputum-negative pulmonary TB if the combining tests cannot provide compelling evidence.