Morbidity and Mortality of Spinal Epidural Abscess in End-Stage Renal Disease Patients: A Case-Control Study

Background: Spinal epidural abscess (SEA) is an uncommon and highly morbid infection of the epidural space. End-stage renal disease (ESRD) patients are known to be at increased risk of developing SEA; however, there are no studies that have described the risk factors and outcomes of SEA in ESRD patients utilizing the United States Renal Data System (USRDS).

Methods: To determine risk factors, morbidity, and mortality associated with SEA in ESRD patients, a retrospective case-control study was conducted using the USRDS. ESRD patients diagnosed with SEA between 2005 and 2010 were identified, and logistic regression was performed to examine correlates of SEA, as well as risk factors associated with mortality in SEA-ESRD patients.

Results: The prevalence of SEA amongst ESRD patients was 0.39% (n = 1,697). Patients with SEA were more likely to be male [adjusted Odds Ratio (OR) = 1.22], black (OR = 1.19), diabetic (OR = 1.26), with catheter access (OR = 1.29), and less likely to be ≥65 years old (OR = 0.64). Osteomyelitis, bacteremia/septicemia, MRSA, and endocarditis were all significantly associated with increased risk of SEA (OR = 1.54-5.14). Age ≥65 years (HR = 1.45), urinary tract infections (HR = 1.26), decubitus ulcers (HR=1.37), and post-SEA paraplegia (HR = 1.25) were significantly associated with mortality among those with SEA.

Conclusions: As described in previous literature, risk factors for SEA included infections, diabetes, and indwelling catheters. Additionally, clinicians should be aware of the risk factors for mortality in SEA-ESRD patients. As the largest study of SEA to date, our report identifies important risk factors for SEA in ESRD patients, and novel data regarding their mortality-associated risk factors.