[Juvenile multiple xanthogranuloma in a patient with Langerhans cell histiocytosis]

Area of Science:

• Pediatric Dermatology
• Histiocytic Disorders
• Immunohistochemistry

Background:

• Langerhans cell histiocytosis (LCH) is a rare clonal proliferative disorder of Langerhans-like cells.
• Juvenile xanthogranuloma (JXG) is a benign, non-Langerhans cell histiocytic disorder typically presenting in infancy.
• The co-occurrence of LCH and JXG is infrequently reported, posing diagnostic challenges.

Observation:

• A 10-week-old infant presented with erythematous papules, diagnosed as LCH with skull and hepatic involvement.
• Following treatment for LCH, new papules emerged, histologically consistent with JXG (CD68+, S100-, CD1a-).

Findings:

• The case illustrates a rare association between LCH and JXG in a pediatric patient.
• Immunohistochemical analysis differentiated the two conditions, despite overlapping clinical presentations.
• The study underscores the diagnostic complexity when these histiocytic disorders coexist.

Implications:

• This case contributes to the limited literature on the simultaneous occurrence of LCH and JXG.
• Further research is warranted to elucidate the potential pathogenetic links or shared risk factors.
• Accurate diagnosis through biopsy and immunohistochemistry is crucial for appropriate management of pediatric histiocytic disorders.