Lyme neuroborreliosis is a late manifestation of an infection by Borrelia spp., a tick-borne bacterial pathogen that is known for causing Lyme disease and a range of clinical syndromes. The ailment is primarily seen during the summer months and symptoms range from headaches and facial nerve palsy to severe sensory and motor deficits with altered consciousness. The diagnosis mandates a thorough clinical investigation, followed by microbiological studies.
Presentation
Lyme neuroborreliosis (LN) is one of the many forms of Borrelia spp. infection, a spirochetal bacterial pathogen that is transmitted to the human host after a tick bite, specifically from Ixodes species [1] [2] [3] [4]. Higher prevalence is encountered in the United States (where Borrelia burgdorferi is the main causative agent, with an incidence rate of 9.1 cases per 100 000 individuals), and in Europe, where B. garinii, B. afzelii and B. burgdorferi sensu stricto are identified as main pathogenic species [2] [4]. In order for LN to occur, patients first pass through the initial stages of borreliosis (commonly known as Lyme disease) - the appearance of erythema migrans (a sharply-defined circular or "target" lesion that develops in the proximity of the tick bite) within a period of 3-30 days after the bite, and constitutional complaints such as fever, headaches, joint pain, and fever [1] [3] [4]. LN appears when bacteria are disseminated into the peripheral and central nervous system (CNS) and findings are seen either during early stages of dissemination or after a delayed period of weeks to years as a late manifestation [3] [4]. LN is frequently described as a complication of Lyme disease in Europe than in the United States (35% vs. <10%, respectively) [3]. Headaches, cranial nerve palsies (mainly of the facial nerve, presenting as either unilateral or bilateral face droop), and papilledema are nonspecific features, which may prolong the time before a correct diagnosis is made, particularly in children where enteroviral meningitis is a common cause of such symptoms [3] [5]. A more prolonged clinical course and CNS abnormalities, however, are useful distinguishing characteristics [5]. The term Bannwarth's syndrome is used to describe the typical signs of LN (mainly seen in European patients) - lymphocytic meningitis, radiculitis accompanied by sharp pain lasting for weeks or months (with exacerbations during the night), and cranial neuritis [1] [3] [4] [6]. Apart from the involvement of the peripheral nervous system, Borrelia spp. can reach the CNS and cause significant damage to the brain and the spinal cord, presenting as a variable change in consciousness (from mild confusion to severe and life-threatening encephalitis) [1].
Workup
The diagnosis of LN is a difficult one to make without a proper clinical and microbiological investigation. The physician should first conduct a detailed patient interview during which the incidence of tick bites and typical skin lesions must be assessed, whereas a comprehensive travel history (given the fact that visiting endemic areas is a risk factor) may provide important clues as well [1] [4]. Tick-borne disease must be considered in all patients with undisclosed cutaneous and constitutional symptoms in the summer months, as the vast majority of such events occur from May to September [1] [2]. After a detailed physical examination (particularly focused on neurological evaluation), laboratory studies are the cornerstone for confirming the condition. Current recommendations advocate initial serological testing (through enzyme immunoassays or enzyme-linked immunosorbent assays - EIA and ELISA, respectively) of cerebrospinal fluid (CSF) or blood for immunoglobulin (Ig) G and IgM antibodies, followed by more sensitive methods such as Western blot [1] [4] [6] [7] [8]. CSF examination yields lymphocytic pleocytosis with normal biochemical composition [4], and the detection of neutrophilic predominance can firmly exclude Lyme disease as the etiology of neurologic infections [5]. Polymerase chain reaction (PCR) testing is a novel technique that allows identification of pathogenic DNA and its implementation is recommended whenever possible [4] [7]. Imaging studies of the endocranium and the CNS, magnetic resonance imaging (MRI) being the main candidate, reveal nonspecific findings and thus are of limited benefit for discriminating between etiologies of such symptoms [1] [9].
Treatment
The primary treatment for Lyme Neuroborreliosis is antibiotics. Intravenous antibiotics, such as ceftriaxone, are often used for more severe cases, while oral antibiotics like doxycycline may be sufficient for milder cases. The duration of treatment typically ranges from 14 to 28 days, depending on the severity of the symptoms and the patient's response to therapy. Early treatment is crucial to prevent long-term neurological damage.
Prognosis
The prognosis for Lyme Neuroborreliosis is generally favorable if diagnosed and treated early. Most patients experience significant improvement in symptoms following appropriate antibiotic therapy. However, some individuals may have persistent symptoms, such as fatigue or cognitive difficulties, even after treatment. These cases may require additional supportive care and rehabilitation.
Etiology
Lyme Neuroborreliosis is caused by the bacterium Borrelia burgdorferi, which is transmitted to humans through the bite of infected black-legged ticks, also known as deer ticks. The bacteria can spread from the site of the tick bite to various parts of the body, including the nervous system, leading to neuroborreliosis.
Epidemiology
Lyme disease is the most common vector-borne disease in North America and Europe. The incidence of Lyme Neuroborreliosis varies by region, with higher rates in areas where Lyme disease is prevalent. It is most commonly reported in the northeastern and north-central United States and parts of Europe. The risk of infection is highest during the warmer months when ticks are most active.
Pathophysiology
Once Borrelia burgdorferi enters the body through a tick bite, it can disseminate through the bloodstream to various tissues, including the central nervous system. The bacteria can cause inflammation and damage to nerve tissues, leading to the neurological symptoms associated with Lyme Neuroborreliosis. The immune response to the infection also plays a role in the development of symptoms.
Prevention
Preventing Lyme Neuroborreliosis involves reducing the risk of tick bites. This can be achieved by wearing protective clothing, using insect repellent, and performing regular tick checks after spending time in wooded or grassy areas. Prompt removal of ticks can also reduce the risk of infection, as the bacteria typically require several hours to be transmitted after a tick bite.
Summary
Lyme Neuroborreliosis is a serious neurological condition resulting from the spread of Borrelia burgdorferi to the nervous system. Early recognition and treatment with antibiotics are crucial for a favorable outcome. Preventive measures to avoid tick bites are essential in reducing the risk of Lyme disease and its complications.
Patient Information
If you suspect you have been bitten by a tick and are experiencing symptoms such as severe headaches, facial weakness, or limb pain, it is important to seek medical evaluation. Lyme Neuroborreliosis is treatable, especially when caught early. Protecting yourself from tick bites is the best way to prevent Lyme disease and its neurological complications.
References
- Hildenbrand P, Craven DE, Jones R, Nemeskal P. Lyme neuroborreliosis: manifestations of a rapidly emerging zoonosis. AJNR Am J Neuroradiol. 2009;30(6):1079-1087.
- Centers for Disease Control and Prevention (CDC). Lyme disease-United States, 2003-2005. MMWR Morb Mortal Wkly Rep. 2007;56(23):573-576.
- Sinha A, Dietzman T, Ross D, Sulieman S, Fieldston E. Lyme neuroborreliosis: a diagnostic headache. Hosp Pediatr. 2014;4(6):400-404
- Subedi S, Dickeson DJ, Branley JM. First report of Lyme neuroborreliosis in a returned Australian traveller. Med J Aust. 2015 Jul 6;203(1):39-40.
- Shah SS, Zaoutis TE, Turnquist J, Hodinka RL, Coffin SE. Early differentiation of Lyme from enteroviral meningitis. Pediatr Infect Dis J. 2005;24(6):542-545.
- Strle F, Ružić-Sabljić E, Cimperman, J, et al. Comparison of findings for patients with Borrelia garinii and Borrelia afzelii isolated from cerebrospinal fluid. Clin Infect Dis. 2006;43:704-710.
- Aguero-Rosenfeld ME, Wang G, Schwartz I, et al. Diagnosis of Lyme borreliosis. Clin Microbiol Rev 2005;18:484–509.
- Centers for Disease Control and Prevention. Recommendations for test performance and interpretation from the Second National Conference on Serologic Diagnosis of Lyme Disease. MMWR Morb Mortal Wkly Rep 1995;44:590-591.
- Morgen K, Martin R, Stone RD, et al. FLAIR and magnetization transfer imaging of patients with post-treatment Lyme disease syndrome. Neurology. 2001;57:1980–1985.