(Science: chest medicine, pathology) inflammation of the pleura, with exudation into its cavity and upon its surface. It may occur as either an acute or a chronic process. In acute pleurisy the pleura becomes reddened, then covered with an exudate of lymph, fibrin and cellular elements (the dry stage), the disease may progress to the second stage, in which a copious exudation of serum occurs (stage of liquid effusion). The inflamed surfaces of the pleura tend to become united by adhesions, which are usually permanent. The symptoms are a stitch in the side, a chill, followed by fever and a dry cough. As effusion occurs there is an onset of dyspnoea and a diminution of pain. The patient lies on the affected side.
Origin: Gr. Pleuritis