[Immunohistological identification of histiocytosis X cells. Diagnostic value]

Three clinically and histopathologically typical cases of histiocytosis X have been studied by indirect immunofluorescence using monoclonal antibodies on skin lesions. An ultrastructural and immunoperoxidase technique has also been performed. The results confirm that the proliferative skin population of histiocytosis X is composed of Langerhans cells and that histochemical immunology is an effective process which can replace electron microscopy to confirm the diagnosis.