Atraumatic Subdural Hematoma in a Patient on Adalimumab

An atraumatic subdural hematoma (SDH) in a pediatric patient is a rare clinical entity. Although the United States Food and Drug Administration lists SDH as a possible adverse effect of adalimumab therapy for rheumatoid arthritis, the literature lacks reports of SDH in patients on adalimumab. A boy aged 16 years old with a history of ulcerative colitis on adalimumab presented with headache and a right pronator drift. Imaging demonstrated a 2.4-cm SDH on the left with 1.4 cm of midline shift. The patient underwent craniotomy and SDH evacuation, which revealed chronic SDH fluid and subdural membranes. Imaging and culture results did not suggest any other etiology (trauma, vascular malformations, infectious etiologies, or posterior reversible encephalopathy syndrome). The patient was transitioned from adalimumab therapy to ustekinumab therapy and did well without any recurrence.