Pleural effusion in systemic lupus erythematosus.

Three cases of systemic lupus erythematosus (SLE) with pleural effusion are reviewed. The characteristics of the effusions are presented, and the literature pertaining to lupus-related effusions is reviewed. There is great heterogeneity in lupus pleural effusions. The presence of polymorphonuclear neutrophils as the predominant white cell, while consistent with SLE, should raise the possibility of complicating bacterial infection. The presence of lupus erythematosus (LE) cells in the fluid seems to be the most specific diagnostic criterion.