Pleurisy, also called pleuritis, is an inflammation of the pleura, which is the moist, double-layered membrane that surrounds the lungs and lines the rib cage. The condition can make breathing extremely painful.
Sometimes it is associated with another condition called pleural effusion, in which excess fluid fills the area between the membrane’s layers.
The double-layered pleura protects and lubricates the surface of the lungs as they inflate and deflate within the rib cage. Normally, a thin, fluid-filled gap — the pleural space — allows the two layers of the pleural membrane to slide gently past each other. But when these layers become inflamed, with every breath, sneeze, or cough, their roughened surfaces rub painfully together like two pieces of sandpaper.
In some cases of pleurisy, excess fluid seeps into the pleural space, resulting in pleural effusion. This fluid buildup usually has a lubricating effect, relieving the pain associated with pleurisy as it reduces friction between the membrane’s layers. But at the same time, the added fluid puts pressure on the lungs, reducing their ability to move freely. A large amount of fluid may cause shortness of breath. In some cases of pleural effusion, this excess liquid can become infected.
When you breathe, the thin tissues that line your lungs and chest wall, called the pleura, rub together. This isn’t typically a problem because the tissue is satiny and generates no friction. However, when this tissue is inflamed or infected, it becomes irritated and swollen, causing significant pain. This condition is known as pleurisy, or pleuritis.
Pleurisy has a grim fame. It caused the death of a number of historical figures, including Catherine de Medici and Benjamin Franklin.
Pleurisy is no longer a common condition. Over the years, antibiotics have been extremely successful in treating and preventing the bacterial infections that historically were the main causes of pleurisy. Nowadays, most cases of pleurisy are the result of a viral infection and deaths from this illness are quite rare.