Mastocytosis is an uncommon disorder defined by increased and abnormal mast cells in one or more tissues.
Cutaneous mastocytosis (cm) is limited to the skin, with varying degrees of
rash,
pruritus, and disfigurement.
Systemic mastocytosis (sm) typically involves the bone marrow, sometimes in association with other bone marrow disorders, including
chronic myelomonocytic leukemia (cmml).
Mastocytosis has been associated with somatic mutations in the gene encoding the
tyrosine kinase Kit, leading to identification of Kit as a therapeutic target. The Kit inhibitor
imatinib mesylate is approved for aggressive sm. We present an unusual patient with disabling
pruritus from
telangiectasia macularis eruptiva perstans, a subtype of cm, and cmml, but with no evidence of
systemic mast cell disease. She was treated with
imatinib and experienced marked improvement in her
pruritus. Concomitant cm and cmml have not previously been reported, and the present report is the first of successful
imatinib therapy in an adult patient with cm.