Like any part of the body, the spine can become infected. Although spinal infections are uncommon, when they occur, they can be devastating. Treatment often requires the involvement of an infectious disease specialist. The discs of the spine are soft, flexible shock-absorbers between the bones of the spine, called vertebrae. Occasionally, the discs can become infected. When this occurs, the condition is called discitis.

What is Discitis?

As stated above, discitis is when there is an infection of the discs of the spine. Discitis can be caused by bacteria (sometimes called “bugs”), virus, or fungus.  Some parts of the body, such as the mouth and the intestines, are supposed to have bacteria there. This is called “normal flora.” However, the spinal discs are sterile, and have no normal flora.

How Does Discitis Happen?

Discitis most commonly occurs when bacteria directly invade the discs from other parts of the body. This can occur when a person has had surgery or some kind of trauma. Other medical conditions can also put a person at risk for discitis. The most common of these is a bacterial heart infection called endocarditis. Other factors that raise a person’s risk for discitis include IV drug use, diabetes, older age, poor nutrition, and others. The most common “bug” that causes discitis is usually staphylococcus aureus.

When Should I Suspect Discitis?

Discitis can occur in the neck, but it is more common in the low back. Although low back pain is the most common symptom of low back pain, discitis is an unusual cause of low back pain. The pain usually starts slowly and increases gradually over time. Three or more weeks often go by before someone with discitis may present for care. Nerve symptoms such as numbness, tingling and weakness can also be seen. A person with discitis may also feel generally unwell. They may have a fever or feel tired. They may also lose their appetite, become nauseated, and lose weight. The area over the infected disc may be tender to touch. It is important to remember that all of these symptoms are nonspecific, and may be seen with many other causes.

How Do I Get Evaluated For Discitis?

First and foremost, consult with a spine doctor for an evaluation. The most important part of your evaluation will be your doctor taking your medical history and inquiring about risk factors for discitis. Your doctor will also examine you to look for any signs of infection, as well as test you for any nerve damage.

Would I Need Any Lab Testing?

You might. Remember that discitis is rare, and your doctor’s evaluation may be enough to say that you do not have it and will not need any further testing. If more testing is needed, your doctor may request blood testing for infection and inflammation. Again, discitis is an infection, and your doctor may check for various sources of infection. They may even check you for tuberculosis or HIV! DIsc biopsy is generally the gold standard in making the diagnosis.

What About Any Imaging Studies?

If the evidence starts to point towards discitis, your doctor may request some pictures. Plain x-rays and CAT scans can be done, but the best imaging study to look for discitis is an MRI. Doing an MRI with and without contrast is even more helpful. Not everyone can have an MRI, or can have contrast, and your doctor will consider this when deciding what kind of scan you need.

How Is Discitis Confirmed?

Even though discitis is an infection, the blood may or may not show any sign of infection. If all the evidence, including scans, points to possible discitis, then, as stated above, you may need a biopsy. A biopsy is done to take a small sample from the disc. This sample can be tested for the presence of bacteria. If bacteria are found, they can be tested further to see what kind of antibiotics will work. Unless absolutely necessary, antibiotics should not be given until testing is completed, and an appropriate antibiotic is identified.

How Is A Biopsy Done?

A biopsy for discitis is usually done with a needle. The needle is hollow to allow removing a small sample of the disc. The needle can be inserted with CT Scan guidance, or X-ray guidance.

Is Any Other Testing Necessary?

Discitis is an infection, and identifying the source of infection is important.. If no obvious reason for the infection is identified, your doctor may recommend getting your heart checked out for endocarditis with a test called an echocardiogram (“echo”).

What Kind Of Treatment Does Discitis Need?

Discitis is an infection. If it is a bacterial infection, which is usually the case, antibiotics are required. Antibiotics may need to be given through an IV, and for as long as 3 months.

Discitis is usually quite painful, and pain control is a critical component of discitis treatment as well. This is a complex process requiring detailed discussions with the treating physician regarding various options.

Would I Need Surgery?

Would I Need Surgery?Surgery is usually not necessary to treat discitis. It only becomes necessary if antibiotic treatment does not work. Occasionally discitis can affect the spine’s alignment. In this case, surgery may be necessary to fix alignment issues, if there is nerve compromise and extremity symptoms in the arms or legs. Also, hardware may need to be removed until the discitis is cleared up.