Spinal subdural empyema in an immunocompetent patient: illustrative case.

Background: Spinal subdural empyemas are a rare presentation of rapid neurological decline, progressing from radiculopathy to complete paralysis and sensory loss. Although pathogenic mechanisms have been hypothesized, their occurrence in this population of patients remains unclear.

Observations: The authors present the third documented case of an isolated spinal subdural empyema of unclear etiology in an immunocompetent patient with no established risk factors.

Lessons: Successful treatment requires prompt clinical suspicion, radiological diagnosis, and surgical evacuation along with empirical antibiotic treatment. Radiological clarification of the subdural versus the epidural location of the empyema is difficult, while intraoperative durotomy for exploration risks subdural dissemination. In these cases, intraoperative ultrasonography would be a useful adjunct and decision aid. https://thejns.org/doi/10.3171/CASE24464.