Background: Diffuse cutaneous mastocytosis is a rare disease with increased numbers of mast cells and development of blisters, which can be easily overlooked.
Case report: A 6-month-old girl was presented by her parents with acute onset of numerous, disseminated bullae on her body. Histology revealed numerous mast cells in a skin sample and highly elevated serum tryptase levels were detected. The diagnosis of diffuse cutaneous mastocytosis was made. The patient was medically treated with glucocorticoids and antibiotics. Within a few years of time a complete remission of developing bullae, a major clinical improvement as well as a continuous decrease of basal tryptase was seen. Today, the girl is 14 years old and without any apparent limitation due to the disease and in fact she is very successful in competitive sports.
Conclusion: Despite often severe symptoms at first manifestation, this clinical development showing a benign course is typical in children.
Keywords: Blister formation; Bullous mastocytosis; Mast cells; Tryptase; Urticaria pigmentosa.