Multifocal Cutaneous Langerhans Cell Histiocytosis

Abstract

Fundaments: Langerhans cell histiocytosis (LCH) is a disease related to the clonal proliferation of myeloid dendritic cells with morphological, immunophenotypic and ultrastructural similarities to Langerhans cells. It is a rare disease, of unknown etiology, common in white males and affecting 1/200,000/year in children under 15 years. This disease present various forms clinics and is very rare the involvement of the skin (less than 10%), mostly with good prognosis and around 30% of the situations can compromise other organs. We report in this article a rare case of cutaneous limited LCH with multifocal involvement and very low response to chemotherapy. Case report: A six-year-old white girl presenting lesions on the trunk and limbs and progressive increase in number and size, three years ago. In the first dermatological exam was suspected of chronic lichenoid pityriasis, and was prescribed systemic antibiotic therapy, topical corticosteroids and phototherapy, without response. The dermatological examination showed erythematous-violet and infiltrated papules and plaques and residual hypochromic macules in the trunk and limbs. Histopathological examination of the skin revealed dendritic cells similar to LCH (S100+, CD1a+, CD68+). Systemic investigation was normal, confirming cutaneous limited LHC and, despite this, there was low response to Vinblastine and Prednisone therapy.Discussion: LCH presents an exaggerated clonal proliferation of dendritic cells in different tissues, mainly in bones (80%), skin (33%) and pituitary gland (25%). Therefore, the clinical manifestation changes according to the degree and number of compromised systems and organs and the evolution is unpredictable, ranging from spontaneous resolution to rapid progression and death. In general, skin lesions are the first sign of LCH, manifesting as seborrheic dermatitis-like and refractory dermatitis. The diagnosis is suspected by clinical manifestation and defined by histology and immunochemistry. Therapeutic options should be particularized by the extent and severity of the disease.