Comparison of Digital Chest X-Ray and Thoracic Computed Tomography Scan in Childhood Tuberculosis

Imaging is the mainstay of diagnostic criteria in tuberculosis (TB) diagnosis, especially in children; however, the exact role of chest X-ray (CXR) and thoracic CT scan (TCT) still remains controversial. The aim of this study is to compare digital chest X-ray and thoracic CT scan in childhood tuberculosis. In this retrospective comparative study, 38 children under 15 years old with proved diagnosis of TB who were admitted to Massih Daneshvari hospital during 2010 to 2012. Digital chest X-ray and spiral thoracic CT was performed before starting medication. Direct smear for acid-fast bacillus was positive only in 38%. Positive tuberculin skin test was seen in 51% of the cases. Chest X-ray was normal in 36.8% of children, while CT scan was negative only in 21%. Overall sensitivity of thoracic CT scan and chest X-ray were 78.9% and 63.2%, respectively which show no significant difference. CT scan detected lymphadenopathy, nodule/nodular infiltration, collapse and pleural effusion/ thickening significantly better than chest X-ray; however, there was no significant difference between CXR and TCT in detection rate of consolidation/ground glass opacity, bronchiectasis, cicatricial volume loss and cavity/abscess. This study proposed that investigation of children suspicious of tuberculosis by digital chest X-ray is still of great value. It seems that thoracic CT scan in children suspected of tuberculosis infection can be limited only to investigation of complications in selected patients.