Disseminated Juvenile Xanthogranuloma in an Infant Requiring Systemic Therapy: A Case Report

Juvenile xanthogranuloma (XGJ) is a generally benign non-Langerhans cell histiocytosis (non-LCH) that primarily affects infants and children. It typically presents as a single skin lesion. Disseminated and profuse forms remain rare and can pose diagnostic or therapeutic challenges. The classification of histiocytoses has recently evolved, incorporating disseminated XGJ into group "C" of non-LCH cutaneous histiocytoses. While the prognosis for isolated cutaneous forms is excellent, vigilance regarding potential associations (type 1 neurofibromatosis and juvenile myelomonocytic leukemia) and systemic complications remains essential. We report the case of a four-month-old infant presenting with a purely cutaneous disseminated form of XGJ, confirmed by histopathology and immunohistochemistry, which required systemic corticosteroid therapy due to the rapid spread of the lesions. This study involves a four-month-old infant with no significant family history who has been presenting with gradually progressive papular skin lesions for one month. Clinical examination revealed multiple umbilicated, yellowish-brown papulonodules scattered across the face, trunk, limbs, skin folds, genital mucosa, and scalp; a café-au-lait spot was detected on one limb. Dermoscopy revealed a characteristic "sunset" pattern. Histopathological and immunohistochemical analysis (CD68+, CD163+, CD1a-, CD34-, S100-) confirmed the diagnosis. The staging evaluation revealed no abnormalities. After three months of simple monitoring, the extensive spread of the lesions prompted the initiation of oral corticosteroid therapy (1 mg/kg/day), resulting in partial regression at six weeks. Disseminated XGJ in infants remains a rare condition. Although the course is most often self-limiting, justifying an initial conservative approach, certain extensive forms may require systemic treatment. The dermatologist plays a central role in diagnosis, based on a combination of clinical, dermoscopic, histopathological, and immunohistochemical findings, and in the multidisciplinary decision-making regarding treatment.