Visual Dermatologic Case Report: Juvenile Xanthogranuloma of the Labia Majora in a Pediatric Patient.

Juvenile xanthogranuloma (JXG), the most common non-Langerhans cell histiocytosis of childhood, typically presents as a benign, self-limited cutaneous nodule on the head, neck, or trunk during early infancy. Genital involvement is exceedingly rare and poses distinct diagnostic challenges due to anatomic concealment and a broad differential diagnosis. A 5-year-old female presented with a solitary, well-demarcated, tan-brown, firm, dome-shaped papule on the left labia majora that had been intermittently pruritic for approximately 1 month. Dermoscopic evaluation revealed a yellow hue, prompting referral for excisional biopsy. Histopathologic examination demonstrated a dense dermal infiltrate of foamy histiocytes with characteristic Touton giant cells and associated lymphocytes and eosinophils, without cytologic atypia or malignant features, confirming JXG. The patient's dermatologic history included chronic atopic dermatitis, severe xerosis, pityriasis alba, and a stable café-au-lait patch, suggesting an underlying inflammatory cutaneous milieu. No additional lesions or systemic symptoms were identified. Ophthalmologic screening was performed in accordance with established recommendations and was unremarkable. Surgical excision was both diagnostic and curative, with no recurrence on follow-up. This case highlights a rare vulvar presentation of JXG and emphasizes the importance of maintaining diagnostic vigilance for histiocytic disorders in pediatric patients with isolated, persistent dermal papules in uncommon locations. Visual documentation of this entity expands the recognized morphologic and anatomic spectrum of JXG, reinforces the role of biopsy in diagnostically uncertain genital lesions, and facilitates timely reassurance, appropriate surveillance, and prevention of unnecessary intervention.