Cutaneous mastocytosis describes a group of disorders characterized by the presence of excessive numbers of mast cells in the skin. Patients with cutaneous mastocytosis do not fulfill diagnostic criteria for systemic mastocytosis and show no evidence of organ involvement other than the skin.
Forms of cutaneous mastocytosis include three variants recognized by the World Health Organization (WHO) :
●Maculopapular cutaneous mastocytosis (MPCM) or urticaria pigmentosa (UP)
●Diffuse cutaneous mastocytosis
●Solitary cutaneous mastocytoma