Langerhans cell histiocytosis in an adult: good response of cutaneous lesions to acitretin

Summary A 57-year-old man presented with a 2-year history of bilateral erosive lesions on theinguinal region, and erythematous, brown and crusted papules over the trunk.Histological examination of one lesion in conjunction with immunohistochemicalstudy and electron microscopy led to the diagnosis of Langerhans’ cell histiocytosis.After a thorough examination, the only associated findings were retroperitonealfibrosis and hypergonadotrophic hypogonadism with a granulomatous testicularinfiltrate. The patient was treated with oral acitretin for 1 year (with a topicalcorticosteroid for the inguinal lesions), resulting in clearing of the cutaneous lesions.He underwent placement of bilateral double-J ureteral catheters and was started onhormone replacement therapy. At follow-up 1 year after treatment with acitretinceased, the patient remained free of cutaneous lesions and his overall condition,including the retroperitoneal fibrosis, had improved. This case had an uncommoncombination of features, with a good response to acitretin.Langerhans cell histiocytosis (LCH) encompasses aspectrum of syndromes with varied presentations,characterized by infiltration of tissues by Langerhanscells. It most likely results from neoplastic proliferation,although some authors support the hypothesis of areactive process.