Reversible Schamroth Sign.

A 38-year-old woman was admitted to hospital with a 6month history of progressive dyspnea. No changes were observed on physical examination, except for incipient nail-clubbing in the fingers and basal oxygen saturation of 93% at rest. A more detailed examination of the patient’s hands revealed the Schamroth sign, characterized by the absence of a diamond-shaped space between the nails when the backs of the distal phalanges of 2 fingers are placed together1 (Fig. 1A). Chest X-ray was normal, and chest computed tomography revealed some subtle bilateral ground glass infiltrates. Spirometry was performed, showing a restrictive pattern (forced vital capacity 46%). Bronchoscopy with bronchoalveolar lavage revealed 50% lymphocytes.