Lymphatic function in the yellow nail syndrome.

Peripheral oedema is commonly seen in the yellow nail syndrome (YNS). Contrast lymphangiography has shown abnormal collecting lymphatics in some patients with YNS. In this study, lymphatic function in the upper and lower limbs of 17 patients with YNS, in normal controls, and in patients with established classical lymphoedema, has been assessed using quantitative lymphoscintigraphy. Nine subjects with YNS had swelling of the legs and two had features typical of lymphoedema. The lymphatic drainage was significantly reduced in the legs of patients with YNS but not to the level seen in lymphoedema. Lymphatic function was also reduced in the arms in patients with YNS. Venous insufficiency did not contribute to the leg oedema. These results suggest that the underlying cause of YNS is not primarily a lymphatic abnormality. The lymphatic impairment associated with YNS appears to be secondary, and predominantly functional in nature, rather than due to structural changes.