Langerhans cell histiocytosis with characteristic skin involvement.

Langerhans cell histiocytosis (LCH) is a reactive condition in which Langerhans cells accumulate in various tissues and cause damage due, in part, to cytokine production. The etiology has varied from tuberculosis, viruses, lipid abnormality, and immunological abnormality(l). LCH may involve bone, skin, lymph nodes, liver and spleen with hematologic changes and cause fever, malaise and failure to thrive. The skin lesions are characteristically erythematous with greasy scales, scaly papules, nodular and crusted erosions(2). A presumptive diagnosis is possible when histological appearance of biopsy is consistent with diagnosis of LCH. Marker studies involving S100 protein, peanut agglutinin, expression of CD1 complex and electron microscopic demonstration of Birbeck granules further confirm the diagnosis(2,3).