Cutaneous Mastocytosis With Significant Langerhans Cell Infiltration. A Case Report

Abstract

Mastocytosis and Langerhans cell histiocytosis are rare diseases, devolopping from the proliferation of bone marrow cells. Although both diseases may present with various lesions, reddish brown papules are a common manifestation. Darier's sign, which shows activation of mast cells, may help for differential diagnosis. There are only four cases showing prominent Langerhans and mast cells infiltration in the same lesion in the literature. In these cases, because of Darier's sign positivity, dermatologic examination proposes the diagnosis of mastocytosis. We present a ninemonth-old female patient admitted to our dermatology department with reddish brown papules, which are evident in the trunk and neck since birth and urticating upon stroking. In the patient's history and physical examination, there are no other signs or symptoms of systemic involvement. The coexistence of Langerhans and mast cells has been demonstrated by immunohistochemical stainings.