Dermoscopic features of skin lesions in patients with mastocytosis.

OBJECTIVES To evaluate dermoscopic features in a group of 127 patients with mastocytosis in the skin and to investigate the relationship between different dermoscopic patterns and other clinical and biological characteristics of the disease. DESIGN Clinical and laboratory data were compared among patients with mastocytosis grouped according to the different dermoscopic patterns. SETTING Patients were selected from the Instituto de Estudios de Mastocitosis de Castilla La Mancha and the Department of Dermatology of Hospital Universitario Ramón y Cajal from April 1 through September 30, 2009. Patients Overall, 127 consecutive patients (70 females [55.1%] and 57 males [44.9%]; median age, 17 years; range, 0-81 years) with mastocytosis in the skin were included in the study. MAIN OUTCOME MEASURES Evaluation of dermoscopic patterns and investigation of potential predictive factors for more symptomatic forms of the disease according to the need for daily antimediator therapy. RESULTS Four distinct dermoscopic patterns were observed: yellow-orange blot, pigment network, reticular vascular pattern, and (most frequently) light-brown blot. A reticular vascular pattern was identified in all telangiectasia macular eruptiva and some maculopapular mastocytosis. In turn, all patients with mastocytoma displayed the yellow-orange blot pattern. The reticular vascular dermoscopic pattern was associated with the need for daily antimediator therapy; this pattern, together with serum tryptase levels and plaque-type mastocytosis, represented the best combination of independent factors to predict the need for maintained antimediator therapy. CONCLUSIONS Dermoscopy is a feasible method for the subclassification of mastocytosis. Of note, a reticular vascular pattern is more frequently associated with the need for antimediator therapy.