Malabsorption and gastric hyperacidity in systemic mastocytosis. Results of cimetidine therapy.

: Visceral infiltration by mast cells (systemic mastocytosis) is an unusual manifestation of cutaneous mastocytosis. Symptomatic gastrointestinal disease occurs in approximately one-fourth of patients having systemic mastocytosis. An unusual gastrointestinal complication is malabsorption, described in sporadic case reports. A patient with gastric acid hypersecretion and malabsorption is described. Treatment using the histamine H2 antagonist, cimetidine, ameliorated the patient's gastrointestinal symptoms; however, the malabsorption was not resolved.