Skin discoloration in chronic idiopathic thrombocytopenic purpura: detection of local iron deposition by X-ray spectrometry.

A forty-six-year-old woman with a 32 years' history of idiopathic thrombocytopenic purpura presented with black-brown discoloration of her lower limbs. Noninvasive diagnostic X-ray spectrometry (DXS) for determination of trace elements in external tissues revealed striking local iron deposition confined to the skin area with the pigmentary changes. Iron deposition in the skin was probably due to recurrent local purpura caused by longstanding bleeding disorder. Hence DXS proved useful in the detection of local iron load and eliminated the need for skin biopsy in this patient with bleeding tendency.