SPINAL EPIDURAL ABSCESS: PREDISPOSING FACTORS, CLINICAL FEATURES, AND METHODS OF TREATMENT

Twenty-eight patients with pyogenic spinal epidural abscess were treated at the Neurosurgical Department, Zagazig University Hospitals and Health Insurance Hospitals between 1993 and 2003. They were 16 males and 12 females with a mean age of 49 years (range = 26-68 years). Back and/or neck pain was the most common presenting symptom being reported in 92.8% of patients. Neurological deficits were found in 75% of patients and fever in 53.6%. Laboratory investigations revealed elevated ESR in all cases and high WBCs count in 67.8% of patients. Diabetes mellitus was the most common predisposing factof being reported in 9 patients (32.1%). Three patients (10.7%) had previous spinal surgery and two (7.1%) had history of spinal anaesthesia. The source of infection was hematogenous in 4 patients (2 with pneumonia and 2 with urinary tract infection) and a direct spread from paraspinal abscess in 3 cases. In 57.2% of cases, no source of infection could be identified. Staphylococcus aureus was the most common isolated organism (45.8%) followed by Streptococcus viridians (12.5%). Sterile cultures were reported in 21.4% of cases. The diagnosis of spinal epidural abscess was confirmed by CT scan and/or MRI in all cases. Associated spondylodiscitis was found in 9 cases. Twenty-four patients underwent surgery followed by antibiotic therapy and four patients received medical treatment alone. The patients were followed up for a mean period of 10 months. Good outcome was observed in 16 patients (57.1%), fair and poor outcomes were observed in 4 patients for each (14.3%). Four patients died due to direct or indirect effect of the abscess. Factors associated with good outcome included, minimal or no neurological deficits, good general condition, early antibiotic therapy and rapid surgical intervention (less than 72 hours of paralysis). To conclude, spinal epidural abscess is a neurosurgical emergency. Physician awareness about the presenting symptoms and signs of this rare condition is essential to establish early diagnosis and to start proper management. Urgent spinal decompression followed by antibiotic therapy is the treatment of choice. However, certain patients may be managed non-operatively with antibiotic alone but only with very close observation.