Paving-stone CT finding in a pulmonary tuberculosis patient

A 20-year-old man complained cough for more than 2 weeks. He had fever in the afternoon and night sweating. The highest temperature was 39 °C. Routine blood test showed WBC count of 7.55×10⁹/L. Chest X-ray showed consolidation in both lungs. His past medical history was unremarkable. After admission the symptoms didn’t relieved after antimicrobial therapy. Chest computed tomography (CT) scan revealed paving-stone areas in both lungs, and mainly in the upper lobes (Figure 1A,B). There was no enlarged lymph node in the mediastinum. The lung lesions deteriorated at the follow-up CT scan after 15 days (Figure 1C,D), but became more consolidated after 30 days (Figure 2). Clinical diagnosis was pulmonary tuberculosis (TB) or pulmonary alveolar proteinosis. Finally the diagnosis was confirmed by sputum culture of Mycobacterium tuberculosis. During hospitalization the patient had pneumothorax showed by radiography (Figure 3), with absorption after thoracic cavity drainage. The patient underwent anti-TB treatment and was well at four-month follow-up.

Figure 1 (A,B) Chest CT scan [lung window (A) and mediastinal window (B)] at the level of main carina, shows bilateral increased attenuation areas with a prevalent pattern of paving-stone; (C,D) After 15 days of treatment, chest CT [lung window (C) and mediastinal window (D)] scan shows that bilateral lung lesions slightly deteriorated, but without enlarged lymph node in the mediastinum.

Figure 2 Chest CT scan [lung window (A) and mediastinal window (B)] at the same level as Figure 1 after 30 days of treatment, shows bilateral lung lesions became more consolidated with air-bronchogram sign inside.

Figure 3 Chest X-ray shows left pneumothorax.

Pulmonary TB shows variable imaging findings such as micronodules, nodules, masses, consolidation, ground glass opacity, cavitation, bronchiectasis, fibrotic change, parenchyma calcification, lymphadenopathy, pleural thickening, and pleural effusion. Paving-stone CT finding is common in pulmonary alveolar proteinosis and pulmonary fibrosis, however it is rare in pulmonary TB. Pulmonary TB should always be kept in mind in the differential diagnosis of patients with pulmonary lesion.

Acknowledgements

Disclosure: The authors declare no conflict of interest.