Dermatoscopic findings of cutaneous mastocytosis.

BACKGROUND: Mastocytosis is a disorder characterized by the accumulation of mast cells in various organs, most commonly in the skin. Cutaneous mastocytosis (CM) can be classified as nodular CM with solitary or multiple lesions, diffuse CM (erythroderma), and maculopapular CM including the papular/plaque variant, urticaria pigmentosa (UP) and telangiectasia macularis eruptiva perstans (TMEP).

OBJECTIVE: To evaluate the dermatoscopic features of cutaneous mastocytosis.

METHODS: We reviewed the dermatoscopic images of 6 patients who had different variants of cutaneous mastocytosis and who attended the Departments of Dermatology at the Medical University of Ankara, Turkey, and the Medical University of Vienna, Austria.

RESULTS: In UP and in the papular variant of CM the most common structures seen by dermatoscopy were brown reticular lines (pigment network). In TMEP we observed telangiectatic vessels arranged in a reticular pattern.

CONCLUSION: Skin lesions of mastocytosis may exhibit a pigment network, a dermatoscopic feature said to be characteristic of melanocytic lesions. We were also able to identify a new dermatoscopic feature, a reticular vascular pattern that is characteristic of a clinical variant of mastocytosis known as TMEP. This feature may help to differentiate TMEP from other variants of mastocytosis and from other exanthematous skin diseases.