Keys to diagnosis and management of spinal epidural abscesses: 9 years of institutional experience.

Objective: Spinal epidural abscesses (SEA's) are a challenge to diagnose, particularly if there are non-contiguous (skip) lesions. There is also limited data to predict which patients can be treated with antibiotics alone and which require surgery. We sought to assess which demographics, clinical and laboratory findings can guide both diagnosis and management of SEA's.

Methods: All patients with SEA (ICD9 324.1, ICD10 G06.1) between April 2011-May 2019 at a single tertiary center were included. A retrospective EMR review was completed. Patient and disease characteristics were compared using appropriate statistical tests.

Results: 108 patients underwent initial surgical treatment versus 105 that were treated medically initially; 22 (21 %) of those failed medical management. Patients who failed medical management had significantly higher CRP, longer symptom duration, and had higher rates of concurrent non-spinal infections. 9% of patients had skip lesions. Patients with skip lesions had significantly higher WBC, ESR, as well as higher rates of bacteremia and concurrent non-spinal infections. Demographic characteristics and proportion with IVDU, smoking, malignancy, and immunosuppression were similar among the three treatment groups.

Conclusions: 21 % of SEA patients failed initial medical management; they had significantly greater CRP, longer symptom duration, more commonly had neurologic deficits, and concurrent non-spinal infections. 9% of patients had skip lesions; they had significantly higher WBC, ESR, rates of bacteremia and infections outside the spine. These variables may guide diagnostic imaging, and identify those at risk of failing of medical management, and therefore require more involved clinical evaluation, and consideration for surgical intervention.