Researchers reported a case of acute abdomen due to anaphylaxis that was ultimately found to be associated with systemic mastocytosis (SM). The patient, whose case was reported in the International Journal of Emergency Medicine, had a long history of anaphylactic episodes with previously undetermined etiology.

“Among various anaphylactic conditions resulting in acute abdomen, mast cell activation disorders, although rare, are included in the differential diagnosis,” the authors wrote.

“Despite repeated anaphylactic episodes over 30 years, SM in this patient was undiagnosed prior to visiting our hospital, because previous evaluations somehow failed to confirm the mast cell activation disease.”

The patient was a 63-year-old man who presented to the emergency room with acute abdomen, with symptoms including pain, vomiting, diarrhea, and breathing difficulties. He had a long history of anaphylactic episodes for which he received epinephrine, but the cause of these episodes was never conclusively determined.

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The treatment of acute abdomen was successful, and the patient was discharged. A bone marrow biopsy revealed abundant mast cells and suggested an advanced subtype of SM, chronic mast cell leukemia. However, the diagnosis of SM was not confirmed until the patient underwent a biopsy of an area of maculopapular cutaneous mastocytosis, which revealed significant infiltration of mast cells that were positive for CD117, CD25, and CD2.

The authors suspect that the absence of a correct diagnosis was due to previous physicians’ lack of recognition of mast cell activation disorders as a possible cause of acute abdomen. Once diagnosed, the patient was referred to hemato-oncologists for chemotherapy.

The research team recommends that clinicians consider mast cell activation as a cause of anaphylactic gastrointestinal disease when patients present to the emergency room with acute abdomen.


Takagishi T, Miki K, Imashuku S, Takagishi K. Acute abdomen due to anaphylactic intestinal edema associated with systematic mastocytosis: a case report. Int J Emerg Med. 2022;15:38. doi:10.1186/s12245-022-00441-5