Diskitis

What is Diskitis?

Discitis is a rare but severe medical condition, in which the space between the spinal discs, known as the intervertebral disc space, gets infected. These discs play a crucial role in separating and protecting the parts of the spine from one another. When these essential discs get inflamed due to an infection, it can lead to a great deal of pain and discomfort. One of the reasons this condition is both rare and hard to treat is the limited blood flow to these areas of the spine.

The treatment plan usually involves a long period of taking antibiotics, which typically leads to a full recovery without complications. However, if the treatment is delayed or the condition is misdiagnosed, it could result in serious health complications and even become life-threatening.

What Causes Diskitis?

Discitis, a condition causing inflammation between the spinal bones, usually results from one of three things: a direct introduction of the disease, spread through the bloodstream, or, less common, spread from a nearby infection. Identifying what caused the condition can be tricky and sometimes impossible. Typically, a single type of bug is responsible. When tests do find the cause, it’s most often a bacterium called Staphylococcus aureus. Other bacteria like Escherichia coli, Streptococcus pneumoniae, and Salmonella can also cause discitis, but less frequently. In some cases, fungi have been to blame.

Diseases spreading through the bloodstream, like full-body infections or blood poisoning, can cause discitis by first infecting the spine, and then the disc in between the spine bones. These infections may start from other places such as urinary tract infections, pneumonia, or other soft tissue infections. Discitis can also spread from a local infection – for instance, a bone infection adjacent to the spine. Spinal surgeries, diagnostic procedures like lumbar puncture, or local treatments like injections into the area can also lead to discitis.

Blood is supplied to the bits of your spine (vertebrae) and the discs in between them by spinal arteries. In children, these arteries stretch from the end parts of the vertebrae (made of cartilage) into the center of the disc (nucleus pulposus). In adults, these supplies of arteries degenerate, and only stretch into the outer layer of the disc (annulus fibrosis). The network of veins, on the other hand, is in the space surrounding the spinal cord (the epidural space). It’s worth noting that the lower part of the spine (lumbar region) is most often affected, followed by the neck (cervical spine), and then the chest area (thoracic spine).

Risk Factors and Frequency for Diskitis

Discitis is a condition that affects around 0.4 to 2.4 people per 100,000 each year in the United States. It’s more common in children, likely due to changes in the blood supply to the discs in our spines as we get older. However, a second peak in cases happens around age 50. While more common in males, both sexes can develop discitis. The condition often goes hand in hand with other diseases in children, like spinal osteomyelitis and soft-tissue abscesses. The incidence is higher in early childhood and then again during adolescence.

More than half of the cases occur in people who have certain medical conditions or lifestyle factors. The most common of these is diabetes.

• Discitis affects between 0.4 to 2.4 per 100,000 people every year in the US.
• It is more common in children, but a second peak in cases occurs around the age of 50.
• Discitis is more common in males compared to females.
• In children, this condition can be part of a spectrum of diseases including spinal osteomyelitis and soft-tissue abscesses.
• Over half of the cases happen in people who have predisposing medical conditions, the most common being diabetes mellitus.
• Other risk factors include age, being immunocompromised, intravenous drug use, alcoholism, liver cirrhosis, cancer, and kidney dysfunction.

Signs and Symptoms of Diskitis

Getting a correct and timely diagnosis for discitis, an inflammation of the disc space between the bones of the spine, relies heavily on understanding the patient’s symptoms and physical condition. This can be challenging since symptoms can change based on a patient’s age, and it can sometimes take up to six months to get a diagnosis.

In young children, common signs of discitis include back pain, abdominal pain, and reluctance or refusal to walk. The onset of these symptoms usually happens rather quickly. For adults, their symptoms might include back or neck pain, fever, loss of appetite, weight loss, and sometimes even a loss of normal nervous system function. Interestingly, unlike other causes of back pain, the pain from discitis stays at the level of the affected disc and does not usually spread to other areas. Also, if discitis occurs after surgery, the symptoms usually start about 1 to 16 weeks post-operation.

The physical exam might show tenderness over the affected disc, most often in the lower back region. The patient might have a limited or painful range of motion, but their lower body strength, reflexes, and sense of touch are usually normal. A problem with the nervous system is rare, but it can happen in some cases.

• Back or neck pain
• Fever
• Loss of appetite
• Weight loss
• Possible loss of normal nervous system function
• Pain localized to the level of the affected disc
• Delayed symptoms post-surgery (1 to 16 weeks)
• Tenderness over affected disc
• Limited or painful range of motion
• Normal lower body strength, reflexes, and sense of touch
• Possible nervous system issues

Testing for Diskitis

Diagnosing discitis, an infection in the discs between your vertebrae, early on can be a challenge primarily due to the routine nature of initial lab tests and images. However, you might find that your ESR and CRP levels are risen– these are general markers of inflammation in your body. Surprisingly, your white blood cell count could be completely normal.

In order to guide antibiotic therapy, doctors take blood samples to analyze cultures – although often, these cultures don’t show any growth of bacteria. X-ray images usually don’t provide much help either.

Changes on these images, like the narrowing of space between the discs in your spine, or the breakdown of adjacent vertebrae sections, often don’t show up until the disease has progressed over several weeks. But, an MRI scan has proven to be the most accurate for diagnosing discitis.

And, if more proof is needed, a biopsy, which is a small sample taken from your body to look for disease, can confirm the diagnosis and help identify the bacteria causing the infection.

Treatment Options for Diskitis

There’s no consensus among experts on the best way to treat discitis. The options span from immediately using broad-spectrum antibiotics to waiting for the results of culture tests to inform the choice of antibiotic, or even using a spinal brace without antibiotics. However, the most common treatment for discitis is usually antibiotics, and sometimes surgery.

At first, doctors use broad-spectrum antibiotics to cover a wide range of potential bacteria. Once culture tests reveal the specific culprit, doctors can then switch to an antibiotic designed to fight that particular bacteria. It’s critical to initially cover for any Staphylococcus bacteria, which are a common cause of discitis. The antibiotic treatment usually lasts 4 to 6 weeks.

Alongside antibiotics, patients are usually put on bed rest and wear a spinal brace to keep their spine properly aligned. This allows the affected spinal segments to fuse together and heal. Keeping the patient’s pain under control is also a crucial part of the treatment process.

Surgery is typically only considered if the problem is spotted late, or if the disease doesn’t respond to other treatments. Potential reasons to opt for surgery could include nerve damage, a deformed spine, or a disease that doesn’t respond to other treatments.

What else can Diskitis be?

When a doctor is trying to figure out what’s causing a patient’s back pain, and they suspect discitis, they have to consider other conditions as well since they may show similar signs or symptoms. Here’s a list of possible diagnoses, which can range from common causes of back pain to rare infections:

• Osteomyelitis (a bone infection)
• Spinal tumors (abnormal growths in the spine)
• Spinal epidural abscess (a pocket of pus in the spine)
• Spinal fracture (a break in the spine)
• Muscle or tendon injury (damage to the muscles or tendons in the back)
• Disc herniation (when the softer part of spinal disc bulges out of the tough outer ring)
• Inflammatory spondyloarthropathies (a group of diseases that cause arthritis before the age of 45)

The doctor needs to evaluate all these potential conditions carefully to make an accurate diagnosis.

What to expect with Diskitis

The mortality rate for discitis, a disease affecting the spinal discs, ranges from 2 to 11% according to various reports. In general, children seem to bounce back better with treatment and face fewer health issues than adults. The majority of patients get better just with antibiotics, or sometimes with the combination of antibiotics and surgery. Unfortunately, some patients might suffer from a permanent nerve-related disability, usually due to a delay in diagnosis.

Possible Complications When Diagnosed with Diskitis

Complications from discitis, a disease affecting the disc space between your vertebrae, may include changes to the structure of your spine, abnormality in certain sections of the spine, and in a few cases, problems with your nervous system. Babies suffering from this disease can have significant kyphosis, a condition where the spine curves excessively outward.

However, in the overall scenario, children usually have mild symptoms and outcomes. This means that while they might get affected by the disease, it generally does not cause severe issues.

Preventing Diskitis

It’s hard to prevent discitis, a kind of infection that often starts in other parts of the body and then spreads to the spaces between spinal discs. Keeping the rest of the body healthy and free from infections is very important. This is especially critical for people who have diabetes or weakened immune systems, as they are particularly susceptible to this disease. So, focusing on preventing infections can play a key role in warding off discitis in these groups.