[Juvenile xanthogranuloma in a flat xanthoma]

Area of Science:

• Dermatology
• Pediatric Pathology
• Histopathology

Background:

• Juvenile xanthogranuloma (JXG) is a rare, benign histiocytic proliferation typically affecting infants and young children.
• JXG commonly presents as solitary or multiple cutaneous papules, nodules, or plaques.
• The occurrence of JXG on a pre-existing plane xanthoma plaque is an unusual presentation.

Observation:

• A seven-month-old child presented with a juvenile xanthogranuloma on the left flank, superimposed on a plane xanthoma plaque.
• Histopathological examination revealed a typical juvenile xanthogranuloma pattern in the central lesion.
• Foamy cells, characteristic of xanthomas, were observed exclusively around capillary vessels in the peripheral areas of the lesion.

Findings:

• The central part of the lesion showed classic juvenile xanthogranuloma histology.
• The peripheral xanthomatous changes appeared to be associated with the capillary network within the lesion.
• A potential link between the etiopathogenic mechanisms of JXG and the development of surrounding plane xanthoma was hypothesized.

Implications:

• This case suggests that juvenile xanthogranuloma may induce or be associated with secondary plane xanthoma formation.
• Understanding the shared etiopathogenic pathways could offer new insights into xanthogranuloma and xanthoma development.
• Further research is warranted to elucidate the relationship between JXG and plane xanthoma in pediatric patients.