Xanthoma disseminatum

A rare skin disorder characterized by the widespread presence of xanthomas

Xanthoma disseminatum is a rare, non-hereditary disorder characterized by the widespread presence of xanthomas, which are yellowish-brown papules and nodules on the skin. This condition is part of a group of disorders known as non-Langerhans cell histiocytosis.

Presentation

Xanthoma disseminatum typically presents with multiple, symmetrical, yellowish-brown papules and nodules. These lesions are most commonly found on the face, neck, trunk, and flexural areas such as the axillae and groin. The lesions can coalesce to form larger plaques. In some cases, mucosal involvement occurs, affecting areas such as the oral cavity and respiratory tract.

Pathophysiology

The exact cause of xanthoma disseminatum is unknown. It is characterized by the proliferation of histiocytes, which are a type of immune cell derived from monocytes. These histiocytes accumulate in the skin and other tissues, leading to the formation of xanthomas. Unlike other forms of xanthomas, xanthoma disseminatum is not associated with hyperlipidemia.

Diagnosis

The diagnosis of xanthoma disseminatum is primarily clinical, based on the characteristic appearance of the skin lesions. A skin biopsy can be performed to confirm the diagnosis, revealing the presence of foamy histiocytes and Touton giant cells. Immunohistochemistry may show positive staining for markers such as CD68 and factor XIIIa.

Treatment

There is no standard treatment for xanthoma disseminatum, and management is often challenging. Options include:

• Surgical excision of individual lesions
• Laser therapy
• Systemic corticosteroids
• Chemotherapy agents such as cyclophosphamide
• Radiation therapy

The response to treatment varies, and spontaneous regression has been reported in some cases.

Prognosis

The prognosis of xanthoma disseminatum is variable. While the condition is benign and not life-threatening, it can cause significant cosmetic and functional impairment, especially if mucosal involvement leads to respiratory obstruction. The disease may stabilize or regress over time, but persistent or progressive cases can occur.

Related pages

• Xanthoma
• Histiocytosis
• Non-Langerhans cell histiocytosis