21st February 2025

Asbestos-associated pleural disease

Asbestos exposure can lead to a range of benign pleural disease.

Pleural plaques

Pleural plaques are focal areas of benign pleural thickening which develop as a result of asbestos exposure. They are normally bilateral, may be calcified, and typically overlie the 6th to 9th ribs. The apices and costophrenic recesses are usually spared.

Pleural plaques are usually asymptomatic and do not require any intervention or follow-up.

Diffuse pleural thickening

More extensive pleural thickening can also occur following exposure to asbestos (although diffuse pleural thickening can also develop in response to other processes such as infection, inflammation or pleural effusions).

Diffuse pleural thickening is differentiated from pleural plaques by dimensions on CT imaging. In addition, it is often present in the costophrenic recesses (unlike pleural plaques).

Diffuse pleural thickening may restrict lung expansion and lead to breathlessness. Pulmonary function testing will usually demonstrate a restrictive pattern with reduced TLCO but normal KCO.

Benign asbestos pleural effusion (BAPE)

Small unilateral benign pleural effusions can occur in patients who have been exposed to asbestos. The effusions are exudative.

BAPE is usually asymptomatic and may resolve spontaneously but should be investigated if identified given the increased risk of lung malignancy in this patient group.