Epidural abscesses are often caused by bacteria from another infection in the body.
They may cause back pain, which may become severe, and weakness or partial paralysis of the legs, loss of bladder and bowel control, fever, and other serious symptoms.
Doctors use magnetic resonance imaging (MRI) to diagnose an epidural abscess in the spinal cord or, if MRI, is unavailable, myelography followed by computed tomography.
Doctors treat abscesses with antibiotics, and if the abscess is causing serious problems, they drain it immediately.
(See also Overview of Spinal Cord Disorders Overview of Spinal Cord Disorders Spinal cord disorders can cause permanent severe problems, such as paralysis or impaired bladder and bowel control ( urinary incontinence and fecal incontinence). Sometimes these problems can... read more .)
Epidural abscesses in the spinal cord are often caused by another infection, most often in the skin or tissues near the spinal cord. However, sometimes epidural abscesses result from an infection of the heart valves (endocarditis Infective Endocarditis Infective endocarditis is an infection of the lining of the heart (endocardium) and usually also of the heart valves. Infective endocarditis occurs when bacteria enter the bloodstream and travel... read more 
), pressure sores Pressure Sores Pressure sores are areas of skin damage resulting from a lack of blood flow due to prolonged pressure. Pressure sores often result from pressure combined with pulling on the skin, friction,... read more 
, an infection in the bones of the spine (osteomyelitis Osteomyelitis Osteomyelitis is a bone infection usually caused by bacteria, mycobacteria, or fungi. Bacteria, mycobacteria, or fungi can infect bones by spreading through the bloodstream or, more often, by... read more ), or a dental abscess Periapical Abscess A periapical abscess is a collection of pus at the root of a tooth, usually caused by an infection that has spread from a tooth to the surrounding tissues. (See also Overview of Tooth Disorders... read more . Epidural abscesses may also develop after an invasive procedure such as spinal surgery or placement of an catheter in the epidural space.
The bacteria that usually cause these abscesses are Staphylococcus aureus (60%), Escherichia coli or other gram-negative bacteria (15%), or streptococci (10%). Occasionally, the abscess is caused by tuberculosis that affects the spine (Pott disease) or injection drug use. In about one third of people, the cause cannot be determined.
Symptoms of Spinal Epidural Abscess
Symptoms of a spinal epidural abscess begin with back pain. The back over the abscess is tender to the touch. Pain may become severe and is worsened by lying down. Fever is common.
The abscess may put pressure on (compress) the spinal cord. If an epidural abscess occurs in the lower back, it may compress the cauda equina, causing the cauda equina syndrome Cauda Equina Syndrome Cauda equina syndrome occurs when the bundle of nerves that extends from the bottom of the spinal cord is compressed or damaged. The most common cause of cauda equina syndrome is a herniated... read more . People with cauda equina syndrome may lose sensation in the buttocks, genital area, bladder, and rectum (called the saddle area). Their legs may become weak or partially paralyzed. They may retain urine or lose control of the bladder (urinary incontinence Urinary Incontinence in Adults Urinary incontinence is involuntary loss of urine. Incontinence can occur in both men and women at any age, but it is more common among women and older people, affecting about 30% of older women... read more 
) or bowel (fecal incontinence Fecal Incontinence Fecal incontinence is the loss of control over bowel movements. Fecal incontinence can occur briefly during bouts of diarrhea or when hard stool becomes lodged in the rectum ( fecal impaction)... read more ). They may have problems walking. Symptoms may progress over hours to days.
Diagnosis of Spinal Epidural Abscess
Magnetic resonance imaging (MRI)
Doctors may suspect a spinal epidural abscess if people have significant, unexplained back pain, particularly when the spine is tender to the touch or when they have a fever or have had a recent infection or dental procedure.
Spinal epidural abscess is diagnosed using MRI. If MRI is not available, myelography Myelography Diagnostic procedures may be needed to confirm a diagnosis suggested by the medical history and neurologic examination. Imaging tests commonly used to diagnose nervous system (neurologic) disorders... read more 
followed by computed tomography (CT) may be used. Samples of blood and, when possible, samples from the infected areas are taken and sent to a laboratory to be grown (cultured) so that the bacteria causing the abscess can be identified. Examination of the blood sample often detects evidence suggesting infection, such as an elevated white blood cell count.
Treatment of Spinal Epidural Abscess
Antibiotics
If abscesses compress the spinal cord, immediate drainage
Rapid treatment of epidural abscesses is necessary to prevent or minimize problems.
Antibiotics may be sufficient. But if abscesses compress the spinal cord, causing weakness or paralysis in the legs, incontinence, or other serious problems, they are surgically drained immediately. A sample of pus from the abscess is sent to a laboratory to be analyzed and cultured to help identify the bacteria causing the abscess.
Antibiotics to treat the bacteria that are usually involved are given without waiting for test results. They are changed as needed when results of testing are available.
