Perianal presentation of Langerhans cell histiocytosis in children.

Langerhans cell histiocytosis, previously known as histiocytosis X, is a disease whose clinical presentation varies. Although it is uncommon, Langerhans cell histiocytosis may involve the perianal region. We report the case of a 2-year-old boy who presented with perianal ulcerated vegetative lesions and seborrheic dermatitis of the scalp. Biopsy of the lesions showed Langerhans cell histiocytosis. This patient did not have any other organ involvement, which is rare. The outcome was favourable with vinblastine and corticoids.