Spinal infections are serious medical conditions affecting the vertebrae, intervertebral discs, and epidural spaces. These infections can exert pressure on the spinal cord and nerve roots, potentially leading to severe neurological deficits if not diagnosed and treated promptly.
Definition and Pathophysiology
Spinal infection are generally categorized into three types:
Vertebral osteomyelitis: Infection of the vertebral bones, usually via hematogenous spread.
Discitis: Infection of the intervertebral discs, more common in children and older adults.
Epidural abscess: Collection of pus in the epidural space, which can compress the spinal cord.
Viral Myelitis: Direct infection of the spinal viruses, causing inflammation, nerve damage, and neurological deficits.
Most infections are bacterial, with Staphylococcus aureus being the most common pathogen. Tuberculosis-related infections, known as Pott disease, can lead to severe vertebral destruction. Fungal and atypical pathogens are rarer, often affecting immunocompromised patients. Additionally, the Brucella pathogen can cause Brucella spondylitis/spondylodiscitis.
Pathophysiology involves:
Inflammatory response in vertebrae and discs.
Destruction of bone and disc tissue.
Compression of the spinal cord and nerve roots, leading to neurological deficits.
Epidemiology
Spinal infections are rare but potentially life-threatening.
Risk factors include advanced age, diabetes, intravenous drug use, immunodeficiency, and prior spinal surgery.
Males are slightly more affected than females.
Signs and Symptoms
Symptoms often develop gradually and may be subtle initially:
Pain
Localized back, neck, or lumbar pain.
Worsens at night and with movement.
May radiate to limbs in case of nerve compression.
Systemic Symptoms
Fever, chills.
Fatigue, unexplained weight loss.
Neurological Symptoms
Muscle weakness, reflex loss.
Sensory deficits such as numbness or tingling
Bladder and bowel dysfunction in severe cases.
Diagnosis and Evaluation
Clinical Examination
Detailed motor strength and reflex testing.
Sensory evaluation.
Assessment of posture, gait, and balance.
Review of systemic infection signs.
Laboratory Tests
Complete blood count: Often shows elevated white blood cells
C-reactive protein (CRP) and Erythrocyte Sedimentation Rate (ESR): Indicators of inflammation
Blood cultures: Identify causative microorganisms.
Imaging Studies
Magnetic Resonance Imaging (MRI): Gold standard; visualizes discs, vertebrae, epidural space, and spinal cord.
Computed Tomography (CT): Evaluates bone integrity, vertebral collapse, or osteolytic lesions.
X-rays: Useful for late-stage detection of vertebral destruction
Nuclear medicine scans: Bone scintigraphy can detect early infection.
Biopsy
Percutaneous or surgical biopsy provides definitive diagnosis.
Allows pathogen identification and antibiotic susceptibility testing.
Treatment
Management requires a combination of medical and surgical approaches.
1. Medical Management
Antibiotics: Tailored to the identified microorganism, initially intravenous, later oral.
Antituberculosis therapy: Standard multidrug regimen for Pott disease, often 6–12 months.
Antifungal therapy: Used in immunocompromised patients or confirmed fungal infections.
Antibrucella therapy: Combination regimens (e.g., doxycycline with rifampicin, with or without gentamicin and streptomycin) for several months are recommended.
2. Surgical Intervention
Indications for surgery include:
Progressive neurological deficits.
Vertebral instability or collapse.
Epidural abscess or significant purulent collections.
Severe pain unresponsive to medical therapy.
Clinical and radiological progression under the medical treatment
Surgical Techniques
Decompression: Relieves pressure on the spinal cord and nerve roots.
Debridement: Removal of necrotic bone and disc tissue.
Epidural abscess drainage: Evacuates purulent material.
Spinal stabilization and fusion: Rods, screws restore vertebral stability if necessary.
Rehabilitation
Physical therapy to maintain muscle strength and mobility.
Pain management and daily activity optimization.
Multidisciplinary support for recovery.
Complications and Prognosis
Delayed diagnosis or inadequate treatment can result in permanent neurological deficits. Early intervention often leads to full or partial recovery. Long-term follow-up and multidisciplinary care optimize outcomes.