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Pleural disorders may be caused by inflammation, injury, or an imbalance of fluids in the pleural space.
Pleurisy is caused by inflammation in the pleura. The inflammation may happen because of an infection, tumor, or another medical condition.
The inflammation affects the two thin layers of the pleura. This can cause the surface of the layers to become rough and the fluid in between the layers to become sticky. When this happens, the two layers may rub together every time you breathe in instead of gliding past each other.
A chest injury, even an injury that does not break the skin but causes internal damage, can allow air, fluid, or blood to leak into the pleural space. This can cause a pneumothorax or pleural effusion.
Air or blood can also leak into the pleural space as a result of a medical procedure, such as a chest biopsy , mechanical ventilation, or thoracentesis.
Pleural effusions develop when fluid enters the pleural space faster or at a higher amount than the body can reabsorb. This imbalance of fluids can be caused by heart, kidney, or liver failure, or other medical conditions.