Neuroborreliosis is a complication of Lyme disease, occurring when the Borrelia burgdorferi bacteria invades and affects the nervous system. This condition can involve either the central nervous system (brain and spinal cord) or the peripheral nervous system (nerves outside these central structures). Borrelia bacteria are transmitted to humans through the bite of infected Ixodes ticks. If untreated, neuroborreliosis develops in about 10-15% of individuals with Lyme disease.
Neurological Symptoms
Neuroborreliosis can manifest with various neurological symptoms, often appearing weeks to months after the initial tick bite. These symptoms frequently involve the cranial nerves, the meninges (membranes surrounding the brain and spinal cord), and nerve roots. Specific presentations vary, but common patterns are observed.
Cranial Neuritis
Cranial neuritis, inflammation of one or more cranial nerves, is a common sign of neuroborreliosis. Facial palsy, presenting as weakness or paralysis on one or both sides of the face, is a common manifestation, particularly in children. This can resemble Bell’s palsy, causing difficulty with facial expressions, eye closure, or even taste disturbances. While facial palsy can occur as an isolated symptom, it sometimes appears alongside other neurological issues.
Meningitis
Aseptic meningitis, inflammation of the meninges, is another common presentation. Symptoms include headaches (mild to prominent), a stiff neck, fever, and sensitivity to light (photophobia). Nausea and vomiting are also possible, though less common than headaches or neck stiffness. In children, isolated meningitis is observed more frequently than in adults.
Radiculoneuritis
Radiculoneuritis, inflammation of the nerve roots, often causes painful conditions affecting the limbs and trunk. Patients describe sharp, shooting pains that can migrate or change location. Pain may be severe and sometimes mistaken for other conditions, like a herniated disc. Sensory disturbances, such as numbness or tingling, and muscle weakness can also accompany the pain.
The Diagnostic Process
Diagnosing neuroborreliosis involves evaluating a patient’s clinical presentation, reviewing their history, and specific laboratory tests. The process begins by considering symptoms of neurological involvement and inquiring about potential tick exposure. Many tick bites go unnoticed, so a documented bite is not always necessary for suspicion.
Laboratory confirmation relies on blood tests and cerebrospinal fluid (CSF) analysis. Blood tests (serology) detect antibodies produced in response to Borrelia bacteria. While these tests indicate exposure, a positive blood test alone cannot confirm nervous system infection. Antibodies in the blood only suggest a past or current Lyme infection, not necessarily neuroborreliosis.
A lumbar puncture (spinal tap) is a definitive step in diagnosing neuroborreliosis. This procedure collects a CSF sample from the spinal canal for analysis. CSF is examined for inflammation signs, such as increased white blood cells (lymphocytic pleocytosis) or elevated protein levels. Most importantly, CSF analysis can detect antibodies produced within the central nervous system, confirming Borrelia infection of the nervous system.
Treatment Protocols
Neuroborreliosis is treated with antibiotics that target Borrelia bacteria to clear the nervous system infection. Antibiotic choice and administration method depend on the clinical presentation and severity. Common antibiotics include doxycycline, ceftriaxone, cefotaxime, and penicillin G.
For some forms, like isolated cranial nerve palsy, oral doxycycline may be prescribed. More severe cases, or those involving meningitis or significant central nervous system symptoms, often necessitate intravenous (IV) antibiotics. Ceftriaxone is a frequently used IV antibiotic due to its ability to penetrate the blood-brain barrier. Treatment duration typically ranges from 14 to 28 days, with many guidelines recommending 14 to 21 days.
Prognosis and Recovery
With timely diagnosis and appropriate antibiotic treatment, the prognosis for neuroborreliosis is favorable. Most patients experience significant symptom improvement and achieve full recovery. Clinical improvement often begins within days of starting antibiotic therapy.
Despite the good prognosis, recovery can be slow, taking weeks or months for symptoms to fully resolve. A proportion of patients may experience residual symptoms even after completing treatment. These lingering complaints can include fatigue, persistent pain, mild cognitive issues (like problems with concentration or memory), and occasional sensory disturbances. While bothersome, these residual symptoms are distinct from Post-Treatment Lyme Disease Syndrome (PTLDS), a more controversial diagnosis characterized by persistent, non-specific symptoms that lack clear biomarkers and may or may not be directly related to ongoing infection.