Discitis is an infection of the intervertebral disc, a structure that separates the vertebrae in the spine. It is a rare but serious condition that can cause severe back pain, fever, and other symptoms. Discitis can lead to serious complications if not treated promptly. Treatment typically involves antibiotics and possibly surgery to remove the infected tissue.
What is Discitis?
Discitis is an infection that affects the intervertebral discs in the spine. It is a rare condition that can cause severe back pain and other symptoms, such as fever and weakness.
The intervertebral discs are the cushions that sit between the vertebrae in the spine. They are made up of a tough outer layer called the annulus fibrosus and a softer inner layer called the nucleus pulposus. Discitis occurs when bacteria or other microorganisms invade the intervertebral discs and cause an infection.
Causes of Discitis
Discitis is usually caused by one of three things:
- Direct inoculation of bacteria: This is when there is direct injection of bacteria or other mico-organism into the disc. This can occur from trauma or as a complication from surgery.
- Spread through the bloodstream (hematogenous spread): This is when the infection is spread, through the bloodstream, from elsewhere in the body. This can occur when pneumonia or a urinary tract infection, for example, makes its way into the bloodstream and is “seeded” in the disc.
- Spread through nearby structures (contiguous spread): This is when the infection is spread from a nearby structure, such as the vertebrae (an infection known as osteomyelitis).
There are several risk factors that can increase a person’s risk of developing discitis, including:
- Age: Discitis is more common in children (due to increased vascular supply of discs) and older adults.
- Weakened immune system: People with compromised immune systems, such as those with HIV/AIDS or cancer, are at increased risk of infection.
- Chronic medical conditions: Certain medical conditions, such as diabetes and end stage renal disease, can increase the risk of infection.
- Previous surgery: People who have had surgery, particularly spine surgery, may be at increased risk of developing discitis.
- Injections or spinal procedures: Procedures that involve injecting substances into the spine or manipulating the spine can increase the risk of infection.
- Use of certain medications: Some medications, such as corticosteroids and immunosuppressants, can weaken the immune system and increase the risk of infection.
Discitis is a rare condition that occurs in approximately 1 out of every 100,000 people in the United States each year. It is more common in children as well adults over the age of 50. Discitis is more common in males than females.
Symptoms of Discitis
The symptoms of discitis can vary depending on the severity of the infection and the location of the infected disc. Common symptoms may include:
- Back pain
- Weight loss
- Numbness or tingling
- Difficulty walking or standing
If you experience any of these symptoms, it is important to seek medical attention as soon as possible. Early diagnosis and treatment can help prevent the infection from spreading and reduce the risk of long-term complications.
Diagnosis of Discitis
Discitis is usually diagnosed through a combination of medical history, physical examination, labs, and imaging tests.
History and Physical Examination
During the examination, the healthcare provider will ask about the symptoms and the location and severity of the pain. They will ask about your medical history and any risk factors for developing discitis.
Physical exam findings may include
- Tenderness in the affected area
- Decreased range of motion: Discitis may cause stiffness and decreased range of motion in the affected area of the spine.
- Numbness or tingling: The infection may cause numbness or tingling in the back, legs, or arms if nearby nerves are affected.
Lab tests may be used to help diagnose discitis and determine the cause of the infection. Some common lab tests that may be ordered include:
- Complete blood count (CBC): This test measures the number and types of cells in the blood, including red blood cells, white blood cells, and platelets. An elevated white blood cell count may indicate an infection.
- C-reactive protein (CRP) test: This test measures the level of CRP, a protein produced by the liver in response to inflammation. An elevated CRP level may indicate an infection or inflammation.
- Erythrocyte sedimentation rate (ESR): This test measures the rate at which red blood cells settle to the bottom of a tube. An elevated ESR may indicate inflammation or infection.
- Blood culture: This test involves taking a sample of blood and culturing it in a laboratory to identify the specific type of bacteria causing the infection.
Imaging studies are often used to confirm the diagnosis of discitis and to determine the location and extent of the infection. Some common imaging studies that may be used to diagnose discitis include:
- X-ray: X-rays use radiation to produce images of the bones in the spine. X-rays may show signs of infection, such as bone destruction or bone abnormalities.
- Computed tomography (CT) scan: CT scans use X-rays and a computer to produce detailed images of the spine. CT scans may show signs of infection, such as abscesses or areas of inflammation.
- Magnetic resonance imaging (MRI): MRI uses a strong magnetic field and radio waves to produce detailed images of the spine. MRI is particularly useful for identifying soft tissue abnormalities, such as infected intervertebral discs. MRI is considered the “gold standard” imaging study for discitis.
Treatment of Discitis
The treatment for discitis typically involves antibiotics to kill the bacteria and reduce the infection. In some cases, surgery may be necessary to remove the infected tissue. Physical therapy may also be recommended to help strengthen the muscles in the back and improve mobility.
The specific treatment plan for discitis will depend on the severity of the infection, the location of the infected disc, and the overall health of the patient.
Antibiotics are the main treatment for discitis. The specific type of antibiotic and the duration of treatment will depend on the specific type of bacteria causing the infection. Antibiotics may be given orally or intravenously.
In severe cases of discitis, surgery may be necessary to remove the infected tissue. This may involve removing the infected intervertebral disc and fusing the adjacent vertebrae together.
Physical therapy may be recommended to help strengthen the muscles in the back and improve mobility. Physical therapy may include exercises to stretch and strengthen the muscles, as well as techniques to reduce pain and improve function.
It is important to complete the full course of treatment as prescribed by the healthcare provider to ensure that the infection is fully cleared and to reduce the risk of recurrence.
The prognosis for discitis is generally good with prompt and appropriate treatment. The majority of people with discitis respond well to antibiotics and other treatment, and the infection usually resolves within a few weeks.
However, the prognosis may be worse in people with underlying medical conditions, such as diabetes or a compromised immune system, or in those who have severe infections or complications. In some cases, discitis may lead to long-term complications, such as chronic pain or disability.
The risk of long-term complications can be reduced by seeking medical attention as soon as possible if you experience back pain that does not go away or that is accompanied by other symptoms, such as fever, weakness, or difficulty urinating. Early diagnosis and treatment are important to prevent the infection from spreading and to reduce the risk of long-term complications.