Infection of the Spine

Infection of the Spine can be caused by either a bacterial or a fungal infection in another part of the body that has been carried into the spine through the bloodstream. The most common source of spinal infections is a bacterium called staphylococcus aureus, followed by Escherichia coli.

Spinal infections can be classified by the anatomical location involved: the vertebral column, intervertebral disc space, the spinal canal and adjacent soft tissues. Infection may be caused by bacteria or fungal organisms and can occur after surgery. Most postoperative infections occur between three days and three months after surgery.

Giving Best Spine treatment is the speciality of Shreya Hospital in Ghaziabad. Dr. Dev Prasanna Mishra is expert in Spine Medical procedure and treatment having over 20 years of involvement. Orthopedic Division at Shreya Hospital do master treatment and consultancy for all sort of spine contamination.

Vertebral osteomyelitis is the most common form of vertebral infection. It can develop from direct open spinal trauma, infections in surrounding areas and from bacteria that spreads to a vertebra from the blood.

Intervertebral disc space infections involve the space between adjacent vertebrae. Disc space infections can be divided into three subcategories: adult hematogenous (spontaneous), childhood (discitis) and postoperative.

Spinal canal infections include spinal epidural abscess, which is an infection that develops in the space around the dura (the tissue that surrounds the spinal cord and nerve root). Subdural abscess is far rarer and affects the potential space between the dura and arachnoid (the thin membrane of the spinal cord, between the dura mater and pia mater). Infections within the spinal cord parenchyma (primary tissue) are called intramedullary abscesses.

Adjacent soft-tissue infections include cervical and thoracic paraspinal lesions and lumbar psoas muscle abscesses. Soft-tissue infections generally affect younger patients and are not seen often in older people.

Infection of the Spine can be caused by either a bacterial or a fungal infection in another part of the body that has been carried into the spine through the bloodstream. The most common source of spinal infections is a bacterium called staphylococcus aureus, followed by Escherichia coli.

Spinal infections may occur after a urological procedure, because the veins in the lower spine come up through the pelvis. The most common area of the spine affected is the lumbar region. Intravenous drug abusers are more prone to infections affecting the cervical region. Recent dental procedures increase the risk of spinal infections, as bacteria that may be introduced into the bloodstream during the procedure can travel to the spine.

Intervertebral disc space infections probably begin in one of the contiguous end plates, and the disc is infected secondarily. In children, there is some controversy as to the origin. Most cultures and biopsies in children are negative, leading experts to believe that childhood discitis may not be an infectious condition, but caused by partial dislocation of the epiphysis (the growth area near the end of a bone), as a result of a flexion injury.

Symptoms vary depending on the type of spinal infection but, generally, pain is localized initially at the site of the infection. In postoperative patients, these additional symptoms may be present:

• Wound drainage
• Redness, swelling or tenderness near the incision

• Severe back pain
• Fever
• Chills
• Weight loss
• Muscle spasms
• Painful or difficult urination
• Neurological deficits: weakness and/or numbness of arms or legs, incontinence of bowels and/or bladder

The biggest challenge is making an early diagnosis before serious morbidity occurs. Diagnosis typically takes an average of one month, but can take as long as six months, impeding effective and timely treatment. Many patients do not seek medical attention until their symptoms become severe or debilitating.

Laboratory Tests

Specific laboratory tests can be useful in helping to diagnose a spinal infection. It may be beneficial to get blood tests for acute-phase proteins, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels. Both ESR and CRP tests are often good indicators as to whether any inflammation is present in the body (the higher the level, the more likely it is that inflammation is present). As inflammation is the body’s natural response to infection, these markers can monitored to assess the presence of infection and the effectiveness of treatment. These tests alone however, are limited, and other diagnostic tools are usually required.

Identification of the organism is essential, and this can be accomplished through computed tomography-guided biopsy sampling of the vertebra or disc space. Blood cultures, preferably taken during a fever spike, can also help identify the pathogen involved in the spinal infection. Proper identification of the of the pathogen is necessary to narrow the antibiotic treatment regiment.

Imaging studies are necessary to pinpoint the location and extent of a lesion. The choice of specific imaging techniques varies slightly, depending on the location of the infection.

Computed Tomography Scan (CT Scan)

The degree of bone destruction is best imaged on a CT scan. Vertebral osteomyelitis can destroy the vertebral body and lead to spinal deformity (typically kyphosis). By assessing the degree of boney destruction, the amount of spinal instability can be determined and can aid in deciding between non-surgical and surgical treatment options.

The CT scan above shows vertebral osteomyelitis at L3-L4 resulting in destruction of the L3 and L4 vertebral bodies. The second CT shows a thoracic spinal compression fracture due to osteomyelitis causing a kyphotic deformity of the spine.

Magnetic Resonance Imaging (MRI)

MRI with and without gadolinium contrast enhancement has become the gold standard in identifying spinal infection and assessing the neural elements. MRI allows for visualization of the soft tissues that include the nerves, spinal cord, and paraspinal muscles, and adjacent soft tissue around the spinal column. Enhancement of the vertebral body, disc space or epidural space is a key sign of infection; however, other pathologies such as inflammation or tumors must be ruled out.

Spinal infections often require long-term intravenous antibiotic or antifungal therapy and can equate to extended hospitalization time for the patient. Immobilization may be recommended when there is significant pain or the potential for spine instability. If the patient is neurologically and the spinal column is structurally stable, antibiotic treatment should be administered after the organism causing the infection is properly identified. Patients generally undergo antimicrobial therapy for a minimum of six to eight weeks. The type of medication is determined on a case-by-case basis depending on the patient’s specific circumstances, including his or her age.

Nonsurgical treatment should be considered first when patients have minimal or no neurological deficits and the morbidity and mortality rate of surgical intervention is high. However, surgery may be indicated when any of the following situations are present:

• Significant bone destruction causing spinal instability
• Neurological deficits
• Sepsis with clinical toxicity caused by an abscess unresponsive to antibiotics
• Failure of needle biopsy to obtain needed cultures
• Failure of intravenous antibiotics alone to eradicate the infection

The primary goals of surgery are to:

• Debride (clean and remove) the infected tissue
• Enable the infected tissue to receive adequate blood flow to help promote healing
• Restore spinal stability with the use of instrumentation to fuse the unstable spine
• Restore function or limit the degree of neurological impairment

Once it is determined that the patient requires surgery, imaging tools such as plain x-rays, CT scans or MRI can help further pinpoint the level at which to perform surgery.