Chest and Thorax #3

A cavitary lesion is seen at the superior segments of the right lower lobe surrounded by patchy consolidation and smaller cavitating nodules as well as tiny nodular opacities with tree-in-bud pattern.

• Post-primary pulmonary tuberculosis/ reactivation tuberculosis or secondary tuberculosis is the most likely diagnosis

• Primary TB within the lungs develops in either  posterior segments of the upper lobes or superior segments of the lower lobes

• The development of an air-fluid level implies communication with the airway

• A (tree-in-bud sign) denoting endobronchial spread along nearby airways

• Cavitation is uncommon in post-primary TB

Solution:

• Post-primary pulmonary tuberculosis/ reactivation tuberculosis or secondary tuberculosis is the most likely diagnosis – TRUE

• Primary TB within the lungs develops in either  posterior segments of the upper lobes or superior segments of the lower lobes – FALSE

• The development of an air-fluid level implies communication with the airway – TRUE

• A (tree-in-bud sign) denoting endobronchial spread along nearby airways – TRUE

• Cavitation is uncommon in post-primary TB – FALSE

Explanation:

Primary pulmonary tuberculosis

• The initial focus of infection can be located anywhere within the lung. It has non-specific appearances of consolidation or even lobar consolidation

• Cavitation is uncommon in primary TB

• The more striking finding, especially in children, is that of ipsilateral hilar and contiguous mediastinal (paratracheal) lymphadenopathy, usually right-sided

Post-primary pulmonary tuberculosis

• Post-primary pulmonary tuberculosis, known as reactivation tuberculosis or secondary tuberculosis, occurs within the lungs and develops in either posterior segments of the upper lobes or superior segments of the lower lobes

• Post-primary infections are far more likely to cavitate. The development of an air-fluid level implies communication with the airway. Endobronchial spread along nearby airways is a relatively common finding, resulting in tree-in-bud sign

References:

1. Nestor Luiz Müller, Tomás Franquet, Kyung Soo Lee (MD.) et al. Imaging of Pulmonary Infections. (2007) ISBN: 9780781772327 – Google Books

2. Jannette Collins, Eric J. Stern. Chest Radiology. (2008) ISBN: 9780781763141 – Google Books

3. David P. Naidich, Nestor L. Müller, W. Richard Webb. Computed Tomography and Magnetic Resonance of the Thorax. (2007) ISBN: 9780781757652 – Google Books

4. Kazerooni EA, Gross BH. The Core Curriculum: Cardiopulmonary Imaging. (2003) ISBN: 9780781736558 – Google Books

5. Thomas W. Shields, Ronald B. Ponn. General Thoracic Surgery. (2005) ISBN: 9780781738897 – Google Books

6. Jeong Y & Lee K. Pulmonary Tuberculosis: Up-To-Date Imaging and Management. AJR Am J Roentgenol. 2008;191(3):834-44. doi:10.2214/AJR.07.3896 – Pubmed