| Pleural thickening | |
|---|---|
 | |
| Macroscopic appearance of a pleural plaque. | |
| Specialty | Respirology |
Pleural thickening is an increase in the bulkiness of one or both of the pulmonary pleurae.
Causes
| Category | Disease | Features |
|---|---|---|
| Infection | After empyema |
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| After tuberculosis |
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| Active infection with mycobacteria other than tuberculosis, or chronic pulmonary aspergillosis |
|
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| Non-infectious inflammation | Asbestosis |
|
| After pleurodesis |
|
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| After hemothorax |
|
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| After drugs, such as methysergide or bromocriptine |
|
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| Cancer-related | Primary cancer, mainly mesothelioma |
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| Metastasis or invasion, mainly from lung cancer |
|
Pleural plaques
Pleural plaques are patchy collections of hyalinized collagen in the parietal pleura. They have a holly leaf appearance on X-ray. They are indicators of asbestos exposure, and the most common asbestos-induced lesion. They usually appear after 20 years or more of exposure and never degenerate into mesothelioma. They appear as fibrous plaques on the parietal pleura, usually on both sides, and at the posterior and inferior part of the chest wall as well as the diaphragm.