Subdural hygroma associated with axillary cystic hygroma

We present a case of a 4-month-old girl with a history of a huge axillary cystic hygroma since birth, with elective surgical resection of the lesion and subsequent development of infection at the surgery site. During hospitalization for the infection, she developed seizures, a bulging fontanelle, increased head circumference, and widely separated cranial sutures. Brain imaging demonstrated new, large, bilateral subdural fluid collections with membrane enhancement around the left-sided collection. She was managed by subdural tap, bilateral craniotomy, broad-spectrum antibiotics, and subduroperitoneal shunt insertion. Ultimately, she had complete recovery without complications. This case adds to the spectrum of intracranial conditions that have been associated with cystic hygroma.