title: Histiocytosis X--unusual presentation with nail involvement.
mesh_terms: D003937:Diagnosis, Differential; D005260:Female; D006646:Histiocytosis, Langerhans-Cell / Q000175:diagnosis / Q000473:pathology*; D006801:Humans; D007223:Infant; D009260:Nail Diseases / Q000473:pathology*; D009365:Neoplasm Regression, Spontaneous; D010915:Pityriasis / Q000175:diagnosis; D012867:Skin / Q000473:pathology; D012878:Skin Neoplasms / Q000175:diagnosis / Q000473:pathology*