Changing Concepts in Spinal Epidural Abscess: A Report of 29 Cases

Abstract

A review of our recent experience with spinal epidural abscess (SEA) reveals several important changing concepts in diagnosis, etiology, management, and outcome. All cases of SEA seen by our service from August 1975 to July 1989 were reviewed retrospectively, and 29 patients were identified (19 men and 10 women, aged 13-78 years). Abscesses were located in the lumbar (n = 21), thoracic (n = 7), and cervical (n = 1) epidural spaces. Gram-positive organisms were the infectious agent in 72% of the cases, and Staphyloccus aureus was the sole agent in 45% other agents were Gram-negative aerobes (n = 5), a Gram-negative anaerobe (n = 1), Mycobacterium tuberculosis(n = 1), and Sporotrichum schenckii(n = 1), the last occurring in a young woman with acquired immune deficiency syndrome. Seventeen patients had concomitant extraspinal infections. Diagnosis was confirmed by myelography, computed tomography, or magnetic resonance imaging. All patients underwent operative decompression and debridement; 2 required a second procedure for persistent infection. The most common operative findings were pus and granulation tissue in the epidural space (52%); the preoperative course correlated poorly with operative findings. The wound was closed primarily in 84% of cases. Postoperative intravenous antibiotic courses for the bacterial abscesses ranged from 1.5 to 6 weeks (median, 2 weeks), followed by antibiotics given orally for 0 to 6 weeks. Two patients died perioperatively. Neurological outcome was good in 21 patients and fair in 6 (mean follow-up, 1.4 years). Over the last 50 years the spectrum of organisms causing SEA has broadened, and the distinction between acute and chronic SEAs has minimal clinical significance. In addition, magnetic resonance imaging has come to have an adjunctive diagnostic role. Treatment by operative debridement, primary wound closure, and short courses of antibiotics given intravenously and orally has a consistently good result, and prognosis has markedly improved.

Infectious disease of the spine: outcome of rehabilitation

“…6,9 Recent studies have attributed a rising incidence of spinal infection to increasing intravenous drug abuse. 2,3,5,7,10,12 Interestingly, none of our patients belonged to this high risk group. This may be because of the strict drug laws in Singapore and the sti penalties faced by drug addicts.…”

“…Over the 6-year study period, only 26 There are a few possible explanations for this: ®rstly, infections of the spine are uncommon and secondly, recent advances in imaging modalities, medical therapies and surgical techniques have resulted in improved clinical outcomes. 4,12 On the other hand, the mortality rate is high for those with severe disease or delayed diagnosis and treatment, and this group of patients often succumb to their illness or the complications thereof. 2,3 The study population (mean age=56.4 years) was generally older than the patients with traumatic spinal lesions rehabilitated at our centre (mean age=35 years).…”

Extradural infections of the spine

“…8,20,21 However, radiological studies such as MRI may underestimate the severity of cord compression considerably. 14,22 Quite often the neurological picture seems not to be adequately explained by what looks like a small enhancing lesion on MRI. It is important to emphasize that the severity of neurological symptoms and potential cord damage does not correlate to the amount of visible compression.…”

“…18,23 Other factors, such as vascular compromise and spinal venous thrombosis are believed to contribute significantly. 2,3,19 Conventional myelography may still give a more adequate assessment in terms of the severity of cord compression in this entity, 7,14,22 especially if multiple spinal levels are involved. According to our experience, it is not possible to di erentiate between epidural granulomas and abscesses on MRI or any other radiographic study.…”

“…7,9,10,17,22 Repeated postoperative ESR measurements and measurements of C reactive protein (CRP) may indicate successful treatment or alert the physician to a new or not su ciently treated infectious problem.…”