Juvenile xanthogranuloma (JXG) has also been called naevoxanthoendothelioma, xanthoma multiplex, juvenile xanthoma, multiple eruptive xanthoma in infancy, congenital xanthoma tuberosum, xanthoma naeviforme and juvenile giant-cell granuloma.
What is juvenile xanthogranuloma?
Juvenile xanthogranuloma is a type of non-Langerhan's cell histiocytosis (Class IIb). It presents as skin lesions predominantly in infants and young children, more often males, and is present at birth in 20% of cases. However, 10% of cases are adults. It is more common in Caucasians than in those of oriental origin. The cause is unknown.
At first the lesions are smooth and pink bumps, but later develop a yellowish appearance and may become scaly. Most are under 0.5 cm in diameter (papules), but giant nodules may be as large as 2 cm. They may arise on any site of the body, but more frequently appear on the trunk and upper extremities. Occasionally they also appear in the eye or internal organs.
Juvenile xanthogranuloma is difficult to distinguish from several other conditions.
- Benign cephalic histiocytosis
- Generalised eruptive histiocytosis
- Papular xanthogranuloma
They are increasingly thought of as the same condition.
|Benign cephalic histiocytosis|
|Generalised eruptive histiocytoma|
How are these disorders diagnosed?
The diagnosis of juvenile xanthogranuloma and related conditions can be confirmed by a skin biopsy. The lesions are composed of collections of histiocytes. In older lesions, the histiocytes may appear foamy, filled with lipids (fats) or hugely enlarged (giant cells).
Despite the fat-filled histiocytes in the skin, the levels of lipids in the blood are quite normal and juvenile xanthogranuloma and related disorders are not usually associated with any serious abnormality. However 20% also have café au lait macules. Multiple café au lait birthmarks are associated with neurofibromatosis type 1.
Unless they occur in the eyes, juvenile xanthogranulomas are harmless growths and disappear eventually over 2 to 3 years, usually without scarring.
Although individual lesions can be cut out, this will leave a scar. Removal is seldom necessary.