If in doubt, the diagnosis can be confirmed with a skin biopsy that shows a dense infiltrate of foamy histiocytes within the dermis and the classic Touton giant cells (a wreath of nuclei surrounded by eosinophilic cytoplasm).
Sometimes JXG can present at birth or develop rapidly in the first few years of life.
JXGs present as a small firm, round, papule or nodule, ranging from 0.5 cm to 2 cm but larger (“giant”) lesions have been described.
Early on, lesions are erythematous or skin colored (Fig. 8.4), but with time they become yellow (Fig. 8.5).
Usually presents as a single lesion but occasionally multiple JXGs occur.
Lesions are typically asymptomatic but sometimes ulceration or crusting may be seen.
Occasionally extracutaneous lesions may be present (0.3% to 0.5% of cases) and the eye is the most frequent site affected.
Risk factors for ocular involvement include onset of lesions within the first 2 years of life and when multiple cutaneous JXGs appear.
Other affected extracutaneous sites include the liver and lungs. Most visceral lesions spontaneously regress with time.
If in doubt, the diagnosis can be confirmed with a skin biopsy that shows a dense infiltrate of foamy histiocytes within the dermis and the classic Touton giant cells (a wreath of nuclei surrounded by eosinophilic cytoplasm).
Differential Diagnosis 
Management 
Points to Remember