RE-START: Exploring the effectiveness of anti-calcitonin gene-related peptide resumption after discontinuation in migraine.

BACKGROUND AND PURPOSE: According to the latest European guidelines, discontinuation of monoclonal antibodies against calcitonin gene-related peptide (anti-CGRP MAb) may be considered after 12-18 months of treatment. However, some patients may worsen after discontinuation. In this study, we assessed the response following treatment resumption. METHODS: This was a prospective study conducted in 14 Headache Units in Spain. We included patients with response to anti-CGRP MAb with clinical worsening after withdrawal and resumption of treatment. Numbers of monthly migraine days (MMD) and monthly headache days (MHD) were obtained at four time points: before starting anti-CGRP MAb (T-baseline); last month of first treatment period (T-suspension); month of restart due to worsening (T-worsening); and 3 months after resumption (T-reintroduction). The response rate to resumption was calculated. Possible differences among periods were analysed according to MMD and MHD. RESULTS: A total of 360 patients, 82% women, with a median (interquartile range [IQR]) age at migraine onset of 18 (12) years. The median (IQR) MHD at T-baseline was 20 (13) and MMD was 5 (6); at T-suspension, the median (IQR) MHD was 5 (6) and MMD was 4 (5); at T-worsening, the median (IQR) MHD was 16 (13) and MMD was 12 (6); and at T-reintroduction, the median (IQR) MHD was 8 (8) and MHD was 5 (5). In the second period of treatment, a 50% response rate was achieved by 57.4% of patients in MHD and 65.8% in MMD. Multivariate models showed significant differences in MHD between the third month after reintroduction and last month before suspension of first treatment period (p < 0.001). CONCLUSION: The results suggest that anti-CGRP MAb therapy is effective after reintroduction. However, 3 months after resumption, one third of the sample reached the same improvement as after the first treatment period.

Long-term effectiveness and tolerability of galcanezumab in patients with migraine excluded from clinical trials: real world evidence of 1055 patients with 1 year follow-up from the Galca-Only registry.

BACKGROUND: Galcanezumab has shown efficacy and effectiveness in the treatment of episodic and chronic migraine (CM), however, the population represented in randomized clinical trials (RCTs) differs from the population observed in real-world setting. To describe the long-term effectiveness and tolerability of galcanezumab in clinical practice in patients excluded from RCTs. METHODS: Multicenter prospective cohort study of consecutive patients with chronic and high-frequency episodic migraine (HFEM) with prior failure to three or more migraine preventive drugs, treated with galcanezumab and followed up for 12 months. RESULTS: We enrolled 1055 patients, aged 50 (IQR: 42-58), 82.9% female, 76.4% chronic migraine, 69% with at least one exclusion criteria for RCTs, including age > 65 (n = 121), concomitant use of onabotulinumtoxinA (n = 185), daily headache at baseline (n = 347), chronic painful syndromes (n = 206), fibromyalgia (n = 101) or treatment resistance (n = 957). The median number of prior preventive treatments was 4 (IQR: 3-5). The retention rate was 90.8%, 76.8% and 71.4% at 3, 6 and 12 months. The main reasons for treatment discontinuation were lack of effectiveness (21.1%) and inadequate tolerability (6.6%). The 30%, 50% and 75% responder rates were 62.6%, 49.8% and 24.2% between weeks 8-12; 60.9%, 48.8% and 24.6% between weeks 20-24; and 59.7%, 48.3% and 24.6% between weeks 44-48. Daily headache at baseline (OR: 0.619; 95%CI: 0.469-0.817) and patient's age (OR: 1.016; 95%CI: 1.005-1.026) were associated with 50% response at weeks 20-24. The variables that were associated with a higher reduction of headache days between weeks 20-24 were patient's age (0.068; 95% CI: 0.018-0.119) and headache days per month at baseline (0.451; 95% CI: 0.319-0.583), while psychiatric comorbidity (-1.587; 95% CI: -2.626-0.538) and daily headache at baseline (-2.718; 95% CI: -4.58-0.869) were associated with fewer reduction in the number of headache days between weeks 20-24. CONCLUSION: This study provides class III evidence of effectiveness and tolerability of galcanezumab in patients with HFEM and CM with comorbidities that would result in exclusion of the pivotal RCTs. Nonetheless, the clinical results over a 12-month period were similar to the efficacy observed in randomized controlled trials. Few patients discontinued the drug due to inadequate tolerability.

Executive summary of the consensus statement of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC), Spanish Society of Neurology (SEN), Spanish Society of Immunology (SEI), Spanish Society of Pediatric Infectology (SEIP), Spanish Society of Rheumatology (SER), and Spanish Academy of Dermatology and Venereology (AEDV), on the diagnosis, treatment and prevention of Lyme borreliosis.

The diagnosis of Lyme borreliosis (LB) is based on the epidemiological history, clinical manifestations and microbiological findings in the early disseminated and late phases of the disease. Related to this fact, microbiological diagnostic techniques have recently appeared. Far from facilitating the diagnosis and the clinical-therapeutic management of LB patients, they are generating confusion. Herein, experts and representatives of Spanish Scientific Societies [Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC), Spanish Society of Neurology (SEN), Spanish Society of Immunology (SEI), Spanish Society of Pediatric Infectology (SEIP), Spanish Society of Rheumatology (SER), and Spanish Academy of Dermatology and Venereology (AEDV)] exposed the executive summary after reviewing the epidemiology, clinical spectrum, available diagnostic techniques for the diagnosis of Borrelia burgdorferi infection, therapeutic and prevention options of LB. By consensus, recommendations for microbiological diagnosis are offered together with those supporting the therapeutic management and prophylaxis of infection.

Executive summary of the consensus statement of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC), Spanish Society of Neurology (SEN), Spanish Society of Immunology (SEI), Spanish Society of Pediatric Infectology (SEIP), Spanish Society of Rheumatology (SER), and Spanish Academy of Dermatology and Venereology (AEDV), on the diagnosis, treatment and prevention of Lyme borreliosis / Resumen ejecutivo del documento de consenso de la SEIMC, SEN, SEI, SEIP, SER y AEDV sobre el diagnóstico, tratamiento y prevención de la borreliosis de Lyme

The diagnosis of Lyme borreliosis (LB) is based on the epidemiological history, clinical manifestations and microbiological findings in the early disseminated and late phases of the disease. Related to this fact, microbiological diagnostic techniques have recently appeared. Far from facilitating the diagnosis and the clinical-therapeutic management of LB patients, they are generating confusion. Herein, experts and representatives of Spanish Scientific Societies [Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC), Spanish Society of Neurology (SEN), Spanish Society of Immunology (SEI), Spanish Society of Pediatric Infectology (SEIP), Spanish Society of Rheumatology (SER), and Spanish Academy of Dermatology and Venereology (AEDV)] exposed the executive summary after reviewing the epidemiology, clinical spectrum, available diagnostic techniques for the diagnosis of Borrelia burgdorferi infection, therapeutic and prevention options of LB. By consensus, recommendations for microbiological diagnosis are offered together with those supporting the therapeutic management and prophylaxis of infection.(AU)

El diagnóstico de la borreliosis de Lyme (BL) se basa en la historia epidemiológica, las manifestaciones clínicas y los hallazgos microbiológicos de las etapas temprana diseminada y tardía de la enfermedad. En relación a este hecho, han aparecido recientemente técnicas diagnósticas microbiológicas que, lejos de facilitar el diagnóstico y el manejo clínico-terapéutico de los pacientes con BL, están generando confusión. Por ello, los expertos y representantes de las sociedades científicas españolas [Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica (SEIMC), Sociedad Española de Neurología (SEN), Sociedad Española de Inmunología (SEI), Sociedad Española de Infectología Pediátrica (SEIP), Sociedad Española de Reumatología (SER) y Academia Española de Dermatología y Venereología (AEDV)] han presentado el documento de síntesis tras revisar la epidemiología, el espectro clínico, las técnicas disponibles para el diagnóstico de la infección por Borrelia burgdorferi, así como las opciones terapéuticas y preventivas de BL. De manera consensuada, se ofrecen recomendaciones para el diagnóstico microbiológico, así como recomendaciones que respaldan el manejo terapéutico y la profilaxis de la infección.(AU)

A 57-year-old man with painful ophthalmoplegia and cavernous sinus involvement: Why this is not Tolosa-Hunt syndrome.

Tolosa-Hunt syndrome (THS) is an idiopathic condition included in the differential diagnosis of painful ophthalmoplegia. Although this was once a common diagnosis, the increasing availability of tests reveals an alternative etiology in many cases. Exclusion of treatable disorders is important, because the prognosis may otherwise be poor. We here describe a patient who presented with painful ophthalmoplegia with an infiltrating lesion in the cavernous sinus. Initially suspected of THS, he had a fatal evolution, and postmortem evaluation revealed cervicocephalic actinomycosis. Actinomycosis diagnosis is often missed, and still represents a challenge to the clinician. We highlight pearls and pitfalls to establish a proper diagnosis to avoid missing a treatable condition in patients with suspected THS.

Drip and ship and mothership models of mechanical thrombectomy result in similar outcomes in acute ischemic stroke of the anterior circulation.

BACKGROUND: Stroke therapy has been transformed in recent years due to the availability of thrombolysis and mechanical thrombectomy (MT). Whether transferring the patient directly to a comprehensive stroke center (CSC, mothership model) is better than taking them to a primary stroke center (PSC) and then to a CSC for MT (drip and ship) is unclear but has important implications. We compared the performance of both models in a district of the Basque country, Spain. METHODS: This is a retrospective analysis of prospectively collected data of all acute ischemic stroke patients consecutively admitted to the Neurology Department of two institutions and eligible for MT over a 36-month period with anterior circulation large vessel occlusion (LVO). One center applied the mothership model and the other the drip-and-ship. The two models were compared in terms of mortality and functional status assessed by modified Rankin (mRS) scale at 90 days. As a surrogate of the effectiveness of the two models, all times pertinent to stroke therapy were recorded. RESULTS: A total of 187 patients were evaluated subjected to MT with the drip-and-ship model and 188 with mothership, with a median NIHSS of 15. Prior to MT, 17% of the drip-and-ship patients received thrombolysis and 26% in the mothership. Neither mortality rate nor mRS showed statistically significant differences 90 days after stroke. The time lapse from stroke to MT was optimal in both models; albeit being 10 minutes longer in the drip-and-ship model, it had no impact on patients' outcomes. CONCLUSIONS: Drip-and-ship and mothership models can provide optimal and similar results in acute stroke patients in terms of mortality and functional status at 90 days. Their coexistence may alleviate the burden of CSC thus facilitating the access of more stroke patients to advanced therapies in an equitable manner.

Pearls & Oy-sters: Arteriovenous Malformation With Sinus Thrombosis and Thalamic Hemorrhage: Unusual Cause of Parkinsonism and Dementia.

Deep cerebral venous thrombosis is an uncommon condition, which usually produces headache, altered consciousness, and ocular movement abnormality. Parkinsonism occasionally occurs when there is basal ganglia involvement. We report a case of a 78-year-old man who presented with a rapidly progressive parkinsonism with poor response to dopaminergic therapy. The patient had bilateral and symmetrical hypokinesia, rigidity, and marked gait impairment with festination. Brain MRI showed bilateral thalamic hyperintensity on T2-weighted and FLAIR sequences, with right thalamic and intraventricular hemorrhage due to straight sinus thrombosis. Angiography revealed an arteriovenous malformation in the quadrigeminal cistern with afferent supply from the posterior cerebral arteries, as well as partial thrombosis of the vein of Galen and half of the straight sinus. No predisposing factor for thrombosis was found. Given the location and size of the malformation, and the substantial amount of thalamic and intraventricular hemorrhage, conservative management was decided, with slow but progressive gait improvement. The presence of deep cerebral venous thrombosis should be suspected in cases of rapidly progressive parkinsonism with cognitive decline. As in this case, thrombosis may be secondary to a deep arteriovenous malformation, a very rare occurrence that may require specific therapy.

Frequency and Characterization of Movement Disorders in Anti-IgLON5 Disease.

OBJECTIVE: Anti-IgLON5 disease is a recently described neurological disease that shares features of autoimmunity and neurodegeneration. Abnormal movements appear to be frequent and important but have not been characterized and are under-reported. Here we describe the frequency and types of movement disorders in a series of consecutive patients with this disease. METHODS: In this retrospective, observational study, the presence and phenomenology of movement disorders were assessed with a standardized clinical questionnaire. Available videos were centrally reviewed by three experts in movement disorders. RESULTS: Seventy two patients were included. In 41 (57%) the main reason for initial consultation was difficulty walking along with one or several concurrent movement disorders. At the time of anti-IgLON5 diagnosis, 63 (87%) patients had at least one movement disorder with a median of three per patient. The most frequent abnormal movements were gait and balance disturbances (52 patients, 72%), chorea (24, 33%), bradykinesia (20, 28%), dystonia (19, 26%), abnormal body postures or rigidity (18, 25%), and tremor (15, 21%). Other hyperkinetic movements (myoclonus, akathisia, myorhythmia, myokymia, or abdominal dyskinesias) occurred in 26 (36%) patients. The craniofacial region was one of the most frequently affected by multiple concurrent movement disorders (23 patients, 32%) including dystonia (13), myorhythmia (6), chorea (4) or myokymia (4). Considering any body region, the most frequent combination of multiple movement disorders consisted of gait instability or ataxia associated with craniofacial dyskinesias or generalized chorea observed in 31(43%) of patients. In addition to abnormal movements, 87% of patients had sleep alterations, 74% bulbar dysfunction, and 53% cognitive impairment. Fifty-five (76%) patients were treated with immunotherapy, resulting in important and sustained improvement of the movement disorders in only seven (13%) cases. CONCLUSIONS: Movement disorders are a frequent and leading cause of initial neurological consultation in patients with anti-IgLON5 disease. Although multiple types of abnormal movements can occur, the most prevalent are disorders of gait, generalized chorea, and dystonia and other dyskinesias that frequently affect craniofacial muscles. Overall, anti-IgLON5 disease should be considered in patients with multiple movement disorders, particularly if they occur in association with sleep alterations, bulbar dysfunction, or cognitive impairment.

Neurologic Manifestations in a Prospective Unselected Series of Hospitalized Patients With COVID-19.

BACKGROUND: An increasing number of neurologic problems are being described in coronavirus disease 2019 (COVID-19) disease, but their frequency and type have not been defined. In this study, we sought to determine the extent of neurologic manifestations of COVID-19 in a prospective series of unselected patients admitted to the general medicine wards of our hospitals due to COVID-19 and who were examined by a team of neurologists. METHODS: Eight neurologists provided medical attention to patients hospitalized for COVID-19 to provide medical support to other hospital units tasked with the care of an increasingly larger influx of patients with COVID-19. A series of 100 consecutive, unselected patients were evaluated systematically, including a questionnaire that collected medical information derived from the initial examination and the medical history. RESULTS: Eighty-eight percent of the patients had 1 neurologic manifestation associated with COVID-19 during hospitalization. Most common were anosmia-dysgeusia and headache (44% each), myalgias (43%), and dizziness (36%). Less frequent were encephalopathy (8%), syncope (7%), seizures (2%), and ischemic stroke during the period of hospitalization (2%). Anosmia and headache associated with younger patients with less severe disease, and both were associated with each other and with serum inflammatory markers. Encephalopathy was associated with fever and syncope and with markers of inflammation. CONCLUSIONS: Neurologic disturbances are common in patients with COVID-19, particularly if patients are evaluated by neurologists. There is a wide variety of neurologic conditions, some of them severe, in the spectrum of COVID-19 disease that will benefit from an evaluation by practicing neurologists.

Chronic severe methanol intoxication after repeated mask cleansing due to fear of COVID-19: A new risk of coronaphobia.

BACKGROUND: Disproportionate fear of contracting COVID-19 (coronaphobia) may result in inappropriate use of preventive measures that could, in turn, result in severe harm to the patient. OBJECTIVE: To describe a patient with subacute parkinsonism and cognitive dysfunction and magnetic resonance imaging (MRI) evidence of bilateral deep white matter and basal ganglia damage. CASE PRESENTATION: A 56-year-old female presented with a 4-week history of insomnia, cognitive decline, and parkinsonism. Brain MRI revealed a bilateral lesion of both globus pallidus, deep white matter, and cerebellar hemispheres. Her son reported that, for the previous month, she had been cleaning her facial mask three times a day with a pure methanol solution as a disinfectant due to an intense fear of acquiring COVID-19. Previously, she had used 97% isopropyl alcohol and had inadvertently switched to methanol. After the exposure ended, she slowly improved but 4 months later she remains severely disabled. CONCLUSIONS: The repeated exposure to methanol vapor, the MRI findings, and the absence of other etiologies for her cognitive and parkinsonian features led to the diagnosis of chronic methanol intoxication with severe central nervous system damage. Misinformation is a likely contributory factor to such scenario. Efforts should be made by the scientific community to educate the general public on avoiding self-damaging behaviors as a result of coronaphobia.

Neurological reasons for consultation and hospitalization during the COVID-19 pandemic.

BACKGROUND: COVID-19 disease affects the nervous system and led to an increase in neurological consults for patients at admission and through the period of hospitalization during the peak of the pandemic. METHODS: Patients with clinical and laboratory diagnosis of COVID-19 that required a neurologic consultation or those who presented with neurological problems on admission that led to a diagnosis of SARS-CoV-2 infection during a 2-month period at the peak of the pandemic were included in this study. Demographic and clinical variables were analyzed. RESULTS: Thirty-five patients were included. The presenting neurologic manifestations on admission led to the diagnosis of COVID-19 in 14 patients (40%). The most common reasons for consultation during the hospitalization period were stroke (11), encephalopathy (7), seizures (6), and neuropathies (5) followed by a miscellaneous of syncope (2), migraine (1), anosmia (1), critical illness myopathy (1), and exacerbation of residual dysarthria (1). The most common neurological disturbances were associated with severe disease except for neuropathies. Patients with encephalopathies and seizures had markedly increased D-dimer and ferritin values, even higher than stroke patients. RT-PCR was performed in 8 CSF samples and was negative in all of them. CONCLUSION: Neurological disturbances represent a significant and severe burden in COVID-19 patients, and they can be the presenting condition that leads to the diagnosis of the viral infection in a high percentage of patients. Evidence of direct viral mechanisms was scarce, but the pathogenesis of the diverse manifestations remains enigmatic.

Akinetic mutism and status epilepticus due to Epstein Barr virus encephalitis.

Neurological complications of Epstein Barr virus (EBV) infection are infrequent and may include occasionally encephalitis, usually with a benign evolution. We here report on an aggressive case of EBV encephalitis in a 14-year-old boy with extensive basal ganglia involvement, and to a lesser degree of brain cortex who presented atypically with akinetic mutism and non-convulsive status epilepticus, requiring intensive care but showed a favorable outcome. EBV encephalitis is uncommon and its best management is unclear. Its pathophysiology is not well understood but could include autoimmunity. Onconeuronal and synaptic antibodies were negative in serum and cerebrospinal fluid, including the dopamine D2 receptor. To the best of our knowledge, this is the first report to evaluate antibodies to D2 receptors in EBV encephalitis. Corticosteroid therapy is usually recommended but the use of acyclovir is controversial. Intensive care is required in severe cases to assure a favorable outcome.

Predictors of in-hospital mortality after ischemic stroke: A prospective, single-center study.

BACKGROUND AND AIMS: Stroke is the second leading cause of death around the globe. Studies examining the predictors of in-hospital mortality and the impact of complications on early outcome of acute ischemic stroke are scant. The aim of this study was to identify predictors of in-hospital mortality in patients with acute ischemic stroke. METHODS: This was a prospective, single-center study of patients with acute ischemic stroke consecutively admitted to the Neurology Department of a general hospital during a 2-year period (from January 1, 2010 to December 31, 2011). Prospective data from this single-center study included variables related to sociodemographics, comorbidities, and medical complications, together with in-hospital mortality. Since stroke mortality may impact differently by sex and is also influenced by hospital length of stay, we proceeded to stratify by these variables. RESULTS: Six-hundred and seventy-three patients were included. Overall, in-hospital mortality rate was 7.13%. Stratifying by length of stay in-hospital (< 7 days and ≥ 7 days), we observed that within the first week, overall mortality was related to a history of previous stroke, higher stroke severity, and to cardiovascular and respiratory complications. After 7 days, the main factor independently associated with overall in-hospital mortality was stroke severity (National Institutes of Health Stroke Scale (NIHSS) ≥ 14, odds ratio (OR): 17.15; 95% CI, 3.06-96.07).Stratifying by sex, we observed that females had a worse outcome if there was a history of prior stroke (OR: 3.29; 95% CI, 1.19-9.10), higher stroke severity (NIHSS ≥ 14, OR: 16.63; 95% CI, 4.66-59.31), and cardiovascular complications (OR: 29.70; 95% CI, 5.70-154.8). Among men, stroke severity (NIHSS ≥ 14, OR: 23.19; 95% CI, 5.69-94.56), respiratory infections (OR: 3.84; 95% CI, 1.32-11.20), and older age had significant negative impact. CONCLUSIONS: Stroke severity and potentially modifiable complications (respiratory infections and cardiovascular complications) confer an increased risk of in-hospital death in both women and men, particularly during the first week of admission.

An open-label prospective study of the real-life use of onabotulinumtoxinA for the treatment of chronic migraine: the REPOSE study.

BACKGROUND: The PREEMPT Studies established onabotulinumtoxinA as preventive treatment for adults with chronic migraine (CM). The purpose of the REal-life use of botulinum toxin for the symptomatic treatment of adults with chronic migraine, measuring healthcare resource utilisation, and Patient-reported OutcomeS observed in practice (REPOSE) Study was to observe real-life, long-term (24-month) use of onabotulinumtoxinA in adults with CM and report on the utilisation, effectiveness, safety, and tolerability. METHODS: The REPOSE Study was a European, open-label, multicentre, prospective, noninterventional study. Patients received onabotulinumtoxinA approximately every 12 weeks according to their physician's usual practice, guided by the summary of product characteristics (SPC). Patients were observed for 24 months after initiating onabotulinumtoxinA treatment. Outcome measures were collected at baseline and all administration visits and included onabotulinumtoxinA injection practices, headache-day frequency, Migraine-Specific Quality-of-Life Questionnaire (MSQ), EuroQol 5-Dimension Questionnaire (EQ-5D), and adverse drug reactions (ADRs) to evaluate safety/tolerability. RESULTS: Of 641 patients enrolled, 633 received ≥1 dose of onabotulinumtoxinA for a total of 3499 treatment sessions. At baseline, mean (SD) age was 45.4 (11.7) years; patients were predominantly women (85.3%). Injection practices closely followed the SPC in mean dosage (155.1 U) and injection sites per session (31.4), with the exception of a prolongation of the recommended 12-week dosing interval, with 79.1% of patients receiving ≥1 treatment session that was > 13 weeks after the previous treatment session. Headache-day frequency was reduced from a baseline mean (SD) of 20.6 (5.4) to 7.4 (6.6) days at administration visit 8 (P < 0.001). Each MSQ domain (restrictive, preventive, and emotional) was significantly reduced from baseline through each administration visit (P < 0.001). The median EQ-5D total and health state scores were significantly improved from baseline through each administration visit (P < 0.001). Overall, 18.3% of patients reported an ADR; most were mild to moderate intensity, with only 1.3% of patients reporting a serious ADR. Eyelid ptosis (5.4%), neck pain (2.8%), and musculoskeletal stiffness (2.7%) were the most frequently reported. CONCLUSIONS: Long-term, real-world preventive treatment of CM with onabotulinumtoxinA showed effectiveness with a sustained reduction in headache-day frequency and significant improvement in quality-of-life measures. ADRs were mild to moderate, with no new safety concerns identified. TRIAL REGISTRATION: Trial registration number: NCT01686581. Name of registry: ClinicalTrials.gov. URL of registry: https://clinicaltrials.gov/ct2/show/NCT01686581 . Date of retrospective registration: September 18, 2012. Date of enrolment of first patient: July 23, 2012.

Lyme Neuroborreliosis: Clinical Outcomes, Controversy, Pathogenesis, and Polymicrobial Infections.

Lyme borreliosis is the object of numerous misconceptions. In this review, we revisit the fundamental manifestations of neuroborreliosis (meningitis, cranial neuritis, and radiculoneuritis), as these have withstood the test of time. We also discuss other manifestations that are less frequent. Stroke, as a manifestation of Lyme neuroborreliosis, is considered in the context of other infections. The summary of the literature regarding clinical outcomes of neuroborreliosis leads to its controversies. We also include new information on pathogenesis and on the polymicrobial nature of tick-borne diseases. In this way, we update the review that we wrote in this journal in 1995. ANN NEUROL 2019;85:21-31.