Clinical features of the yellow nail syndrome.

The yellow nail syndrome is a rare cause of exudative pleural effusions. Diagnosis is based on the presence of typical clinical features, striking nail changes, lymphedema, and pleural effusions of undetermined etiology. There is no direct relationship between the syndrome and primary immunologic disorders, malignancies, endocrine abnormalities, or connective tissue diseases. In patients with symptomatic pleural effusions, pleurodesis is beneficial but no treatment for the nail changes has been devised.