Spinal epidural abscess in hemodialysis patients: report of three cases and review of the literature.

Spinal epidural abscess (SEA) is a rare infection that can evolve to severe permanent neurologic deficit or death if the diagnosis is delayed. We report three cases of SEA in hemodialysis patients and summarize nine previously reported cases occurring in hemodialysis patients, with detailed comparisons to series of SEA from the general medical literature. Among these 12 patients, hemodialysis catheters and arteriovenous grafts were the major source of infection, in contrast to the usual skin source. Staphylococcus aureus was implicated in all cases, but in one patient Bacteroides fragilis also was isolated from both the resected arteriovenous fistula and the SEA, and Escherichia coli was isolated from the arteriovenous fistula. The classic syndrome of SEA includes fever, backache, and local spinal tenderness, followed by progressive radicular and cord compression signs and symptoms. In this series, back pain and radicular pain were common at presentation, but only a minority had fever, back tenderness, weakness, or leukocytosis. Cerebrospinal fluid was typically abnormal but culture negative, whereas blood and epidural abscess cultures were frequently positive. Plain x-ray films, bone scans, and plain computed tomography scans had low diagnostic yield, and magnetic resonance imaging with gadolinium had a sensitivity of 80%. Only myelography or computed tomography-myelography gave consistently correct diagnoses. The clinical outcome was poor, with one patient deceased and seven with severe weakness or paralysis. Early intervention provided a higher likelihood of good outcome, whereas late intervention and preoperative neurologic deficits portended a poor functional result. Because of the high incidence of bacteremia in hemodialysis patients, we recommend that symptoms of fever, backache, and spinal tenderness be promptly evaluated for SEA before signs or symptoms of cord compression develop. Early recognition and treatment with antibiotics and decompressive laminectomy is generally associated with a better outcome.