Independent predictors of failure of nonoperative management of spinal epidural abscesses.

BACKGROUND CONTEXT: The notion that all patients with spinal epidural abscess (SEA) require surgical decompression has been recently challenged by reports of successful medical management of select patients with SEA.

PURPOSE: The purpose of this study was to identify the independent variables that determine success or failure of medical management of SEA.

STUDY DESIGN/SETTING: This was a retrospective, case-control study.

PATIENT SAMPLE: Patients 18 years or older with diagnosis of SEA admitted to our institution during the study period were included in the sample.

OUTCOME MEASURES: The outcome measure was successful management of SEA by eradication of the infection without worsening of neurologic deficits.

METHODS: All patients admitted to our health-care system with a diagnosis of SEA from 1993 to 2011 were identified and the data were retrospectively collected. Patients 18 years or older diagnosed with SEA were included. Excluded were those with postsurgical SEA or phlegmon without an abscess and those with a complete spinal cord injury from SEA for longer than 48 hours.

RESULTS: A total of 355 patients with average age of 60 years met our inclusion criteria. Of the patients who initially underwent nonoperative treatment, 54 patients failed medical management and 73 patients were successfully treated without surgery. Univariate and multivariate analysis identified incomplete or complete spinal cord deficits as the most significant risk factor for failure of medical management. Age older than 65 years, diabetes, and methicillin-resistant Staphylococcus aureus (MRSA) were also independent risk factors for failure. An algorithm for probability of failed antibiotic management of spinal epidural abscess predicted 99% probability of failure for patients with all four of these risk factors.

CONCLUSIONS: SEA treated with medical management alone has a very high risk for failure if the patient is older than 65 years with diabetes, MRSA infection, or neurologic compromise. In the absence of these risk factors, nonoperative management of spinal epidural abscess may be considered as the initial line of treatment with close monitoring.