NORMOLIPEMIC PAPULAR XANTHOMATOSIS IN ERYTHRODERMIC ATOPIC-DERMATITIS

We describe papular xanthomatosis that progressively developed in a pa tient with longstanding erythrodermic atopic dermatitis and normal lip id metabolism and without an associated systemic disease. Light micros copy showed a lobulated aggregate of sometimes foamy histiocytes. Ultr astructurally, these histiocytes contained lipid inclusions and lacked features of Langerhans or epithelioid cells. Other granulomatous skin diseases such as tuberculosis, sarcoidosis, or foreign body granuloma were excluded by histologic study, polarizing microscopic examination , electron microscopy, and microbiologic investigations. Nevertheless, these xanthomas showed an antigen expression pattern similar to that found in noninfectious granulomas (CD1a(-), MS-1(-), CD11c(+), MRP-8/- 14(+), 25F9(+), RM 3/1(+/-), CD36((+))), indicating that normolipemic papular xanthomatosis may be a reactive process and should not be incl uded among the true cutaneous non-Langerhans cell histiocytoses.