Abstract

Langerhans cell histiocytosis (LCH) is a rare pediatric disease of unknown etiology, the skull being the most affected site. We present a healthy 4-year-old girl with a scalp swelling, without history of head trauma or other symptoms. Physical examination and bloodwork had no significant findings. The radiography and CT-scan revealed an osteolytic lesion, without intracranial involvement. Pathologic examination diagnosed a LCH. Being a single lesion in a low-risk location, she was put on clinical surveillance. The swelling regressed and she awaits imaging reevaluation. LCH can go unnoticed when symptoms resemble trauma or other conditions, but it should be considered when a mass arises from the skull in children.

Keywords:Langerhans cell histiocytosis; Osteolytic lesion; Scalp swelling; Multinucleated cells; CD1a; S-100 marker