Acute Appendicitis as the First and the Only Presentation of Systemic Mastocytosis.

Systemic mastocytosis is a rare myeloproliferative disorder characterized by abnormal accumulation of mast cells in a variety of organs. When affecting the gastrointestinal tracts, it may manifest with steatorrhea, malabsorption, hepatomegaly, splenomegaly, portal hypertension, and ascites, among others. To our knowledge, only one case of systemic mastocytosis has been reported affecting the appendix. We present another case of a 47-year-old woman who was admitted for right-sided acute abdominal pain and found to have systemic mastocytosis in her appendectomy specimen as the first and only manifestation of her disease.