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

Background: 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. Materials and Methods: 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. Results: 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. Conclusions: 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.