Photo Credit: Mr. Suphachai Praserdumrongchai

The following is a summary of “CT Scan Differences of Pulmonary TB According to Presence of Pleural Effusion,” published in the December 2023  issue of Pulmonology by Jung, et al.

CT scans often show interlobular septal thickness and subpleural micronodules in people with TB pleural effusion. These CT scan traits help them distinguish between an empyema that isn’t caused by tuberculosis and one that is. For a study, researchers sought to determine whether there was a link between the number of subpleural micronodules and interlobular septal thickening and the presence of pleural fluid in people with pulmonary TB. They looked back at CT scan results of people with pulmonary tuberculosis and looked at micronodules and where they were found (peribronchovascular, septal, subpleural, centrilobular, and random), as well as large opacities (consolidation/macronodule), cavitation, tree-in-buds, bronchovascular bundle thickening, interlobular septal thickening, lymphadenopathy, and pleural effusion. Patients were split into two groups based on whether they had pleural fluid. The results of the clinicoradiologic tests on the two groups were then compared. They showed the Benjamini-Hochberg critical value for correcting CT scan results from multiple tests, with a false discovery rate 0.05.

Out of the 338 consecutive patients with pulmonary TB who had CT scans, 60 were not included because they also had other lung illnesses. A significant difference was found between the groups of patients with pulmonary TB with pleural effusion (47/68, 69% vs 30/210, 14% in pulmonary TB without effusion; P <.00001; Benjamini-Hochberg [B-H] critical value = 0.0036) and those without pleural effusion (55/68, 81% vs 134/210, 64%; P =.009; B-H critical value = 0.0107). The latter had more subpleural nodules and thickening between the lobular septae. On the other hand, patients with lung TB and pleural effusion were less likely to have tree-in-buds (20/68, 29% vs 101/210, 48%, P =.007, B-H critical value = 0.0071).

People with lung TB who had pleural effusion were more likely than those who did not have pleural effusion to have subpleural tumors and thickening of the septum. TB affecting the lymphatics in the peripheral interstitium may be linked to the growth of pleural fluid.

Source: sciencedirect.com/science/article/abs/pii/S0012369223009534