Lyme disease is a bacterial infection caused by Borrelia burgdorferi that is transmitted through the bite of infected ticks. If left untreated, the bacteria can spread to various parts of the body and cause serious complications. One of the most severe complications that can occur is when the bacteria affect the nervous system, including the brain.
How does Lyme disease affect the brain?
Lyme disease bacteria can spread to the brain and central nervous system in a process called neuroborreliosis. This occurs in about 15% of untreated Lyme disease cases. The bacteria cause inflammation in the tissues surrounding the brain and spinal cord, which leads to neurological symptoms. They can also directly infect the brain and spinal cord tissues.
There are three main stages of Lyme neuroborreliosis:
- Early neuroborreliosis – Occurs within weeks of a tick bite. Causes symptoms like stiff neck, severe headache, light and sound sensitivity, and facial palsy.
- Early disseminated neuroborreliosis – Occurs within months of infection. Involves moderate to severe headaches, memory problems, and mood changes.
- Late neuroborreliosis – Occurs years after infection. Causes cognitive impairments, severe headaches, numbness, tremors, and even psychosis in rare cases.
Without treatment, the bacteria will continue spreading through the central nervous system and provoke worsening inflammation and damage.
What are the neurological symptoms?
Some of the common neurological symptoms that can occur when Lyme disease affects the brain include:
- Severe headaches
- Stiff neck
- Light and sound sensitivity
- Facial palsy (drooping on one side)
- Difficulty concentrating and multitasking
- Short-term memory problems
- Mood changes, irritability, depression
- Sleep disturbances
More severe neurological manifestations can also happen in late-stage untreated cases:
- Nerve pain or unusual sensations (paresthesia)
- Tremors or loss of muscle coordination
- Severe cognitive impairment resembling dementia
- Peripheral neuropathy causing numbness or weakness
- Hearing loss or ringing in the ears
- Visual disturbances
- Dizziness and balance issues
Can Lyme disease cause permanent brain damage?
If Lyme neuroborreliosis is diagnosed and treated early, most patients recover fully without permanent damage. However, there is a risk of permanent neurological damage if the infection goes untreated for a long time.
Studies show that even after antibiotic treatment, some patients continue experiencing cognitive deficits and brain fog. One study found brain abnormalities on MRI scans in 69% of patients who had been treated for Lyme neuroborreliosis years earlier.
The potential mechanisms for persistent symptoms include:
- Chronic inflammation causing lasting tissue damage
- Autoimmune reactions triggered by Lyme bacteria
- Remaining pockets of bacteria evading antibiotics
- Complications from co-infections transmitted by ticks
Patients with prolonged illness report disabling neurological symptoms interfering with their quality of life. The cognitive impairments they experience can range from mild to severely debilitating in some cases.
What are the possible complications?
Potential neurological complications that can result from Lyme disease infection in the brain include:
- Encephalopathy: Diffuse brain dysfunction causing cognitive impairment, personality changes, and involuntary motor movements.
- Encephalitis: Brain inflammation leading to fever, severe headaches, seizures, and altered mental status.
- Meningitis: Swelling of the membranes covering the brain and spinal cord. Causes stiff neck, severe headache, light sensitivity, nausea.
- Cranial neuritis: Inflammation of cranial nerves that control eye movements, facial muscles, hearing, and swallowing.
- Radiculoneuritis: Nerve inflammation causing shooting pain, numbness or weakness in the limbs.
- Vasculitis: Blood vessel inflammation in the brain. Can lead to stroke or brain hemorrhage.
While rare, untreated CNS Lyme disease has also been linked to an increased risk of developing Parkinson’s disease and dementia later in life. Prompt antibiotic treatment can help prevent these devastating complications.
How is Lyme neuroborreliosis treated?
The main form of treatment for Lyme disease affecting the brain is antibiotics. Usually, a 2-4 week course of doxycycline, amoxicillin, or ceftriaxone (intravenous) is prescribed. The earlier treatment is started, the better the outcome.
In patients with severe neurological symptoms, IV antibiotics may be given in the hospital initially. Corticosteroids like prednisone are sometimes prescribed as well to help reduce brain inflammation.
Rehabilitation therapy can help those dealing with lingering cognitive or motor deficits after treatment. Non-pharmacological therapies are also used to manage neurological pain, fatigue, and mood problems associated with Lyme disease.
How can you prevent Lyme neuroborreliosis?
The best way to avoid complications like Lyme neuroborreliosis is to take steps to prevent tick bites and detect Lyme disease early:
- Avoid areas with high grass or brush when ticks are active.
- Use EPA approved insect repellents when outdoors.
- Wear long pants and sleeves when in wooded areas.
- Check your skin and clothing for ticks after being outdoors.
- Remove attached ticks as soon as possible using tweezers.
- Keep an eye out for symptoms of Lyme and seek early treatment.
- Get the Lyme disease vaccine if eligible.
Catching Lyme disease quickly and getting appropriate antibiotic treatment can help eradicate the infection before the bacteria have a chance to spread to the nervous system.
Conclusion
Lyme neuroborreliosis is a severe condition that can occur when Lyme disease bacteria spread to the brain and nervous system. It can cause debilitating neurological symptoms like severe headaches, memory problems, and brain fog. Without treatment, permanent brain damage is possible in some cases. However, most patients recover fully if Lyme neuroborreliosis is caught and treated early. Preventing tick bites remains the best protective strategy against this debilitating complication.