A spinal cord abscess is caused by an infection inside the spine. An abscess of the spinal cord itself is very rare. A spinal abscess usually occurs as a complication of an epidural abscess.

Pus forms as a collection of:

• White blood cells
• Fluid
• Live and dead bacteria or other microorganisms
• Destroyed tissue cells

The pus is commonly covered by a lining or membrane that forms around the edges. The pus collection causes pressure on the spinal cord.

The infection is usually due to bacteria. Often it is caused by a staphylococcus infection that spreads through the spine. It may be caused by tuberculosis in some areas of the world, but this is not as common today as it was in the past. In rare cases, the infection may be due to a fungus.

The following increase your risk for a spinal cord abscess:

• Back injuries or trauma, including minor ones
• Boils on the skin, especially on the back or scalp (rare)
• Complication of lumbar puncture or back surgery
• Spread of any infection through the bloodstream from another part of the body (bacteremia)
• Injecting illicit drugs

The infection often begins in the bone (osteomyelitis). The bone infection may cause an epidural abscess to form. This abscess gets larger and presses on the spinal cord. The infection can spread to the spinal cord itself.

A spinal cord abscess is rare. When it does occur, it can be life threatening.

Symptoms may include any of the following:

• Fever and chills.
• Loss of bladder or bowel control.
• Loss of movement of an area of the body below the abscess.
• Loss of sensation of an area of the body below the abscess.
• Low backache, often mild, but slowly gets worse, with pain moving to the hip, leg, or foot. Or, pain may spread to the shoulder, arm, or hand.

Your health care provider will perform a physical exam and may find the following:

• Tenderness over the spine
• Spinal cord compression
• Paralysis of the lower body (paraplegia) or of the entire trunk, arms, and legs (quadriplegia)
• Changes in sensation below the area where the spine is affected

The amount of nerve loss depends on where the abscess is located on the spine and how much it is compressing the spinal cord.

Tests that may be done include:

• Complete blood count (CBC)
• CT scan of the spine
• Draining of abscess (may require surgery)
• Gram stain and culture of abscess material
• MRI of the spine

The goals of treatment are to relieve pressure on the spinal cord and cure the infection.

Surgery may be done right away to relieve the pressure. It involves removing part of the spine bone and draining the abscess. Sometimes it is not possible to drain the abscess completely.

Antibiotics are used to treat the infection. They are usually given through a vein (IV).

How well a person does after treatment varies. Some people recover completely.

An untreated spinal cord abscess can lead to spinal cord compression. It can cause permanent, severe paralysis and nerve loss. It may be life threatening.

If the abscess is not drained completely, it may return or cause scarring in the spinal cord.

The abscess can injure the spinal cord from direct pressure. Or, it can cut off the blood supply to the spinal cord.

Complications may include:

• Long-term (chronic) back pain
• Loss of bladder/bowel control
• Loss of sensation
• Male impotence
• Return of infection
• Weakness, paralysis

Go to the emergency room or call 911 or the local emergency number, if you have symptoms of spinal cord abscess.

Thorough treatment of boils, tuberculosis, and other infections decreases the risk. Early diagnosis and treatment are important to prevent complications.

Abscess - spinal cord

Rajasekaran S, Viswanathan VK, Shetty AP. Primary infections of the spine. In: Steinmetz MP, Berven SH, Benzel EC, eds. Benzel's Spine Surgery. 5th ed. Philadelphia, PA: Elsevier; 2022:chap 44.

Tunkel AR. Subdural empyema, epidural abscess, and suppurative intracranial thrombophlebitis. In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 9th ed. Philadelphia, PA: Elsevier; 2020:chap 91.

Williams KD. Infections and tumors of the spine. In: Azar FM, Beaty JH, eds. Campbell's Operative Orthopaedics. 14th ed. Philadelphia, PA: Elsevier; 2021:chap 42.

Updated by: Jatin M. Vyas, MD, PhD, Professor in Medicine, Harvard Medical School; Associate in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital, Boston, MA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.