Spinal infections are typically bacterial infections that are spread to the spine through the bloodstream — though fungal or viral infections can also occur. The most common cause of spinal infection is Staphylococcus aureus (staph infection), followed by E. coli bacteria.
Risk factors for spinal infections include:
- A weakened or suppressed immune system.
- Inadequate diet and nutrition.
- Advanced age.
- Long-term steroid use.
- Intravenous drug abuse.
- Some diseases, such as cancer and diabetes.
An infection can occur after spinal procedures or surgery, despite careful preventive measures. The risk for infection increases with longer duration surgeries, use of surgical implants or other medical devices, or repeated surgeries in the same area of the body. Postsurgical infections usually appear between three days and three months after surgery.
Some urology procedures — such as cystoscopy, a diagnostic procedure that uses a scope to examine the urinary tract — can also lead to spinal infection. Veins in the lower spine also drain blood from the pelvis, allowing bacteria from the bladder area to reach the spine.
Types of Spinal Infection
Spinal infections are classified by where the infection is located: the spinal column (backbone or spine), discs (discitis, and the spinal canal that surrounds the spine and nearby soft tissue. The most common types of infection include vertebral osteomyelitis (affecting spinal bones) and discitis.
A spinal epidural abscess is a less common type of spinal infection, but potentially life threatening if not treated early. It can be bacterial or fungal and may develop if infections elsewhere in the body — such as a urinary tract infection — spread through the bloodstream. This type of abscess can occur at any age, but is most common in people 50 and older.
You can lower your risk of infection by practicing good personal hygiene, maintaining a healthy lifestyle and taking antibiotics as directed by your doctor to prevent an antibiotic-resistant bacterial infection. To further lower your risk, avoid smoking — it weakens your immune system and makes you more vulnerable to infection.
Spinal infection symptoms vary depending on the cause and how quickly the infection spreads. An infection may develop slowly and eventually cause back stiffness, muscle spasms or pain in the area affected. Other symptoms that develop over time include fever, chills, headache, unexplained weight loss, and swelling, redness or warmth in the affected area.
In some instances, spinal infections cause neurological symptoms due to decreased function of the brain, spinal cord, muscles or nerves. These symptoms may include loss of balance, weakness, vision changes, or an inability to speak, feel or move.
Symptoms also will vary depending on the type of infection:
- Postsurgical infection symptoms may include increased pain and redness around the incision, or pus, odor or fluid draining from the wound.
- Spinal canal infection symptoms may include severe pain, muscle weakness, difficulty controlling bowel or bladder function, or even paralysis.
- Soft-tissue infection symptoms may include pain in your side or abdomen, or pain that radiates to your hip or thigh.
Diagnostic X-rays, CT scans or MRIs — as well as other specialized testing, such as bone scans — can help doctors confirm a spinal infection. In cases of deep bone or disc infections, your doctor may perform a needle culture using localized anesthetic.
In addition, your doctor may take a blood culture, or a culture of the infected area, to identify an infection and the type of bacteria or fungus causing it. He or she may also use other blood tests — such as a white blood cell count or a C-reactive protein test — to look for signs of an infection.
Spinal infection treatments typically include oral and intravenous antibiotics, bracing to stabilize the spine as it heals and rest. If it’s a tuberculosis infection, a year of oral antibiotic treatment may be necessary.
In some instances, your doctor may recommend surgery to clean the area, remove infected tissues and stabilize the spine. Spinal fusion may be performed to address instability due to weakened or removed bones or tissue. The surgeon may implant a device, such as a supportive cage, to help prevent the injured area from moving while it heals.