By: Paul Louis, MD
Back pain is one of the most frequent symptoms that patients come to the emergency department for. In fact, there are over 3,000,000 visits to the emergency department annually for back symptoms (1). Spinal epidural abscess (SEA) is a rare diagnosis in which there is an infection within the skull or spinal column. The emergency medicine physician is often tasked with diagnosing this rare condition. Because of the significant neurological consequences of delayed diagnosis of SEA, emergency medicine physicians may be retained as spinal epidural abscess expert witnesses.
What is a Spinal Epidural Abscess and why are they dangerous?
A spinal epidural abscess is an infection that is enclosed between the bony confines of the skull or spinal column and the tissue layer called the dura mater. An abscess is, essentially, a collection of pus. When this infection expands, it can compress the nerves. In normal anatomy, there exists a space, the epidural space, between the dura mater and the vertebral wall or skull. In certain at-risk individuals, bacteria can gain access into the epidural space from the blood vessels, or via nearby infected tissue, or sometimes after a spinal procedure. Risk factors for SEA include diabetes, history of injection drug abuse, chronic kidney disease, chronic liver disease, recent spinal procedures, spinal surgery or fractures, indwelling vascular catheters, or other immunocompromising conditions. In cases involving spinal epidural abscesses, a spinal epidural abscess expert witness may be needed to opine on the diagnosis and treatment of same.
How does the infection cause symptoms?
Once the bacteria have invaded the space, they can set up shop, proliferate and cause compression of the nerves in that area. Alternatively, the abscess can cause inflammation of the nearby veins or block the arterial supply of blood. This prevents the flow of blood, oxygen, and nutrients into the space and the removal of toxins out of the space. The epidural space is confined and cannot expand. Expansion of the contents of the limited space can therefore compress and compromise the nerves of the spine and cause paralysis of the extremities below the infection. This infection can also result in loss of control of the urinary bladder and bowels and also cause sexual dysfunction. A spinal epidural abscess expert witness may be called upon to testify as to harm caused by this condition and whether earlier diagnosis and treatment would have prevented harm to the patient.
Why is spinal epidural abscess a commonly missed diagnosis?
SEA is difficult to diagnose. Firstly, spinal epidural abscesses are very rare, occurring in only 2.4 cases per 100,000 persons (3). Fever in a patient with back pain is a concerning sign that may first alert the emergency physician to evaluate for SEA. Physicians should have a high index of suspicion, especially in patients with risk factors to diagnose a spinal epidural abscess discussed previously.
Blood tests such as ESR (erythrocyte sediment rate) or CRP (C-reactive protein) can be obtained if the clinician has suspicion and are usually significantly elevated in SEA (2). The white blood cell count is not a reliable indicator (3). The diagnostic tool optimally used to confirm the diagnosis is the MRI with and without gadolinium (contrast). Since MRIs cannot be done routinely for all patients with low back pain, careful attention to the patient’s risk factors and physical diagnosis is key. A spinal epidural abscess expert witness may be needed to offer an opinion as to why an MRI was or was not performed.
What is the treatment for spinal epidural abscess?
Once a spinal epidural abscess is diagnosed, the next step for the emergency medicine physician is urgent neurosurgical or spinal orthopedic consultation. In most cases, the goal is emergent surgical decompression and drainage of the abscess. In addition to drainage of the pus collection, blood cultures should be obtained, and systemic (intravenous) antibiotic therapy should be administered as soon as possible. If a neurosurgeon or spinal orthopedic surgeon is not available for consultation at that hospital, urgent transfer should be organized. If antibiotics are not administered in a timely fashion and/or a neurosurgeon is not consulted, the disease can progress and leave the patient with permanent disabilities. A spinal epidural abscess expert witness may be needed to opine as to whether the appropriate course of treatment was followed given the circumstances.
Spinal epidural abscess is a challenge to diagnose and can lead to catastrophic injury or death. The earlier SEA is diagnosed and treated, the better the prognosis and chance for a full recovery. The longer the delay in diagnosis, the more likely the patient will suffer long-term, irreversible consequences. If the emergency department evaluation and care provided to a patient presenting with back pain and spinal epidural abscess diagnosis is missed or delayed, the consequences for the patient can be catastrophic. A spinal epidural abscess expert witness may be needed to evaluate whether the standard of care was met in the diagnosis and treatment of SEA.
Dr. Paul Louis is a board-certified emergency medicine physician with over 20 years of practice experience in Emergency Medicine. Throughout the course of his medical career, he has treated over 70,000 patients at trauma centers, community hospitals, urgent care centers, and free-standing emergency departments. He graduated from the University of Miami School of Medicine and completed his residency training at Beth Israel/Mount Sinai in New York City. He has a patent-pending medical device used for respiratory treatments during COVID-19. His current focus is risk management in the emergency department.
Dr. Louis can be reached at DrLouis@medicallegalconsults.com or 561-445-6674. Website: medicallegalconsults.com
2. Vertebral Osteomyelitis, Discitis, and Spinal Epidural Abscess in Adults
Carol E. Chenoweth, MD, Benjamin S. Bassin, MD, Megan R. Mack, MD, Mark E. Oppenlander, MD, Rakesh D. Patel, MD, Douglas J. Quint, MD, and F. Jacob Seagull, Ph.D.
3. Ann Arbor (MI): Michigan Medicine University of Michigan; 2018 Dec. https://www.ncbi.nlm.nih.gov/books/NBK547443/