Yellow nail syndrome with reduced glucose level in pleural fluid.

The yellow nail syndrome, consisting of deformed yellow nails, lymphedema, and pleural effusions, is a rare disorder of unknown etiology. The underlying mechanism in this disease is believed to be hypoplasia of the lymphatic system. To date, only 47 cases of the yellow nail syndrome have been reported. We report an additional case, with a defect in cell-mediated immunity and development of an empyema. The patient also had a very low glucose level in the pleural fluid (10 mg/100 ml or less), which did not increase after loading with oral or intravenously administered glucose. The mechanisms for low levels of glucose in the pleural fluid are discussed.