Elderly female w/ PMHx of TIA, DM, and remote breast Cancer history reportedly in remission presented to the ED w/ c/o R-sided neck pain radiating to her R trapezius for 2 days. No fevers or chills, no Hx of trauma or falls, no vision changes, vague reporting of onset characteristic but could not recall exact time. Patient reported it was associated w/ mild headache and her neck pain was reproducible w/ neck movement. She does not take antipsychotics. No recent travel.
ROS: negative, no CP, no SOB, no N/V/D, no abdm pain, no rash.
Exam:
T 99.0 HR 78 BP 151/90 R 14 O2 Sat 98% on RA
HEENT: EOMI, pupils equal and reactive, throat clear, uvula midline
Neck: +ttp on R trapezius and pain w/ ROM of neck, no masses, no erythema.
CV: no carotid bruit
Neuro: Symmetric 5/5 strength in bilateral upper ext, facial nerves intact, no gross deficits, unremarkable
MSK: no midline spine ttp
Rest of Exam was unremarkable.
CTA of neck was ordered, report read as mild foraminal stenosis of C4 but otherwise unremarkable, no carotid stenosis or dissection, correlate w/ MRI if clinically indicated.
Patient improved after analgesics and muscle relaxant given, follow up was arranged with PMD, patient also given return instructions and reasons to seek immediate medical attention.
Patient returned a few days later w/ persistent pain, had arranged for outpatient MRI however it was still pending. Patient had MRI in the ED which revealed an epidural abscess extending from C2-C4, she was admitted and started on appropriate abx.
Spinal Epidural Abscess
A spinal epidural abscess is a rare but important suppurative infection of the central nervous system. A spinal epidural abscess requires prompt recognition and treatment to prevent potentially disastrous complications.
Anatomy:
Only a potential epidural space exists anterior to the cord because the dura is adherent to the vertebral bodies from the foramen magnum down to L1. As a result, the majority of spinal epidural abscesses are located posteriorly; when an anterior abscess occurs, it is usually below L1.
Pathogenesis :
Bacteria can gain access to the epidural space by direct inoculation into the spinal canal (e.g. during spinal or epidural anesthetic procedures or surgery) or hematogenously by direct extension from infected contiguous tissues. Many spinal epidural abscesses begin as focal pyogenic discitis.
As the inflammation progresses and the abscess extends longitudinally in the epidural space, damage to the spinal cord can be caused by the following mechanisms:
-Direct compression
-Thrombosis and/or thrombophlebitis of nearby vasculature
-Interruption of the arterial blood supply
-Bacterial toxins and cytokines
Epidemiology:
Rare, ~10/100,000. Incidence has slightly increased and attributed to increasing age of population, number of epidural/spinal procedures, and capacity for detection w/ MRI. Risk factors include medical procedures, immunosuppression, trauma, diabetes, IV drug abuse, tattoos and acupuncture.
Microbiology:
Most common staph aureus (>60%), TB thought to be more common cause in certain parts of the “developing” World.
Diagnosis:
The physical exam is usually non-specific.
Routine laboratory studies are seldom helpful in the diagnosis. The ESR is usually elevated in both spinal epidural abscess and vertebral osteomyelitis, the leukocyte count may be elevated or normal. In one study of ED patient population only 60% of patients had elevated WBCs at their initial visit. In another prospective study, the ESR was elevated (>20 mm/hour) in all patients (n = 86) with a spinal epidural abscess. However 33% of patients w/out an abscess had ESR elevations. The mean ESR in patients with SEA was significantly elevated (76.5 mm/hour). In another report, the ESR was elevated in 110 of 117 patients (94%) of patients with a spinal epidural abscess. CRP is thought to be less specific for this patient population.
Once the diagnosis is seriously considered, imaging of the spinal column is important. MRI is the preferred test because it is often positive early in the course of the infection and provides the best imaging of the location and extent of inflammatory changes. CT scanning w/ IV contrast is thought to be an acceptable alternative. Myelography is now less recommended.
Treatment:
Surgical decompression and drainage with systemic antibiotic therapy is considered the treatment of choice, however there have been several cases of resolution after diagnostic aspiration and/or antibiotics alone. Duration of therapy is usually 6-8 weeks.
The differential diagnosis is extensive but should include malignancy, discitis and osteomyelitis, meningitis, degenerative disc/bone disease, vascular disease, and zosters.
This patient underwent aspiration and although her cultures were negative (had already been receiving treatment) there were no malignant cells identified.
Special Thanks to Dr. Elaine Rabin for her morning report presentation on this case.
- Pradilla G, Ardila GP, Hsu W, Rigamonti D. Epidural abscesses of the CNS. Lancet Neurol 2009; 8:292.
- Sørensen P. Spinal epidural abscesses: conservative treatment for selected subgroups of patients. Br J Neurosurg 2003; 17:513.
- Ptaszynski AE, Hooten WM, Huntoon MA. The incidence of spontaneous epidural abscess in Olmsted County from 1990 through 2000: a rare cause of spinal pain. Pain Med 2007; 8:338.
- Sethna NF, Clendenin D, Athiraman U, et al. Incidence of epidural catheter-associated infections after continuous epidural analgesia in children. Anesthesiology 2010; 113:224.
- Gosavi C, Bland D, Poddar R, Horst C. Epidural abscess complicating insertion of epidural catheters. Br J Anaesth 2004; 92:294; author reply 294.
- Darouiche RO. Spinal epidural abscess. N Engl J Med 2006; 355:2012.
- Sendi P, Bregenzer T, Zimmerli W. Spinal epidural abscess in clinical practice. QJM 2008; 101:1.
- Chen WC, Wang JL, Wang JT, et al. Spinal epidural abscess due to Staphylococcus aureus: clinical manifestations and outcomes. J Microbiol Immunol Infect 2008; 41:215.
- Davis DP, Wold RM, Patel RJ, et al. The clinical presentation and impact of diagnostic delays on emergency department patients with spinal epidural abscess. J Emerg Med 2004; 26:285.
- Curry WT Jr, Hoh BL, Amin-Hanjani S, Eskandar EN. Spinal epidural abscess: clinical presentation, management, and outcome. Surg Neurol 2005; 63:364
- Davis DP, Salazar A, Chan TC, Vilke GM. Prospective evaluation of a clinical decision guideline to diagnose spinal epidural abscess in patients who present to the emergency department with spine pain. J Neurosurg Spine 2011; 14:765.
