Pleural effusion usually occurs in patients previously diagnosed with rheumatoid arthritis, but it can also occur concurrently with or before the development of the joint manifestations of the disease (Graham, 1990; Chou and Chang, 2002). Patients may present with the signs of pleural effusion: dullness on percussion, diminished or absent breath sounds and vocal fremitus, and egophony at the level of the pleural liquid.