<unk>  is a form of histiocytosis, classified as "non-Langerhans cell histiocytosis", or more specifically, "type 2".
Juvenile xanthogranuloma
Actinic granuloma
Lymphangioma circumscriptum
Pyogenic granuloma
Ichthyosis bullosa of Siemens
Keratosis pilaris
Generalized eruptive histiocytoma
Epidermolysis bullosa