Germline p.D816V ckit mutation in connatal systemic mastocytosis

Background Systemic mastocytosis (SM) is characterized by accumulation of clonal mast cells in bone marrow, liver, spleen, or other visceral organs [1]. More than 90% of patients with SM have a somatic heterozygous activating c-kit mutation, most frequently c.2447A>T/p.D816V [2]. These point mutations result in a sustained activation of KIT, which leads to constant stimulation of mast cells and release of mast cell mediators. While cutaneous mastocytoma is more frequent at pediatric age, SM is rare in children [3].