Atypical lung involvement in a patient with systemic juvenile xanthogranuloma.

Juvenile xanthogranuloma (JXG) is a non-Langerhans cell histiocytosis characterized by xanthoma-like cutaneous lesions. It is a benign condition that is generally asymptomatic. Visceral involvement is uncommon, but when present may occur in various locations and in different combinations. Pulmonary involvement has been reported as bilateral, multiple micro- or macronodular lesions. We present a 10-year-old boy with systemic (skin, lung, liver and kidney) JXG who showed lung involvement with mainly an interstitial pattern. Bilateral multiple micronodules in both lungs and mediastinal adenopathy were also present.