[Diagnostic challenges in systemic mastocytosis with gastrointestinal symptoms].

Mastocytosis is a rare disease. The yearly incidence is 1/100,000 in the general population. The diagnosis is relatively simple when cutaneous manifestations are present, but there are cases when just the mastocyte activation syndromes might call attention on the disease. Symptoms might be diverse, varying case to case, involving different organs and are often considered as allergy. Symptoms come suddenly like flush, collapse, headache, pyrosis, watery diarrhoea that influence the life quality, but sting anaphylaxis might be life threatening if not treated immediately. With this case report, authors aimed to call attention to the importance to take bowel biopsy in cases of watery diarrhoea of non-infective origin even when the macroscopic picture of the bowel looks normal, as histological evaluation of the specimen might prove mastocytic infiltration. Orv Hetil. 2024; 165(18): 717–720.