Dermatographic fixed-drug eruption: another cause of pseudo-Darier's sign.

A 7-year-old boy from El Salvador presented with several well-demarcated 3- to 4-cm round to oval, grey-brown patches on his shoulder and trunk (Figure a) that appeared simultaneously about 1 year previously. The lesions were red initially and thought by the patient's mother and primary care physicians to be bruises, but a hematologist's evaluation was unremarkable. The erythema soon subsided, leaving persistent light-brown spots on the torso. The patient was otherwise asymptomatic.