Antecedent infections in Fisher syndrome: sources of variation in clinical characteristics

Ultrasensitive assay technology and fluid biomarkers for the evaluation of peripheral nerve disease

The field of biomarker discovery is rapidly expanding. The introduction of ultrasensitive immunoassays and the growing precision of genetic technologies are poised to revolutionise the assessment and monitoring of many diseases. Given the difficulties in imaging and tissue diagnosis, there is mounting interest in serum and cerebrospinal fluid biomarkers of peripheral neuropathy. Realised and potential fluid biomarkers of peripheral nerve disease include neuronal biomarkers of axonal degeneration, glial biomarkers for peripheral demyelinating disorders, immunopathogenic biomarkers (such as the presence and titre of antibodies or the levels of cytokines) and genetic biomarkers. Several are already starting to inform clinical practice, whereas others remain under evaluation as potential indicators of disease activity and treatment response. As more biomarkers become available for clinical use, it has become increasingly difficult for clinicians and researchers to keep up-to-date with the most recent discovery and interpretation. In this review, we aim to inform practising neurologists, neuroscientists and other clinicians about recent advances in fluid biomarker technology, with a focus on single molecule arrays (Simoa), chemiluminescent enzyme immunoassays (CLEIA), electrochemiluminescence (ECL), proximity extension assays (PEA), and microfluidic technology. We discuss established and emerging fluid biomarkers of peripheral neuropathy, their clinical applications, limitations and potential future developments.

Anti-GQ1b Antibody Syndrome Presented as Locked-In Syndrome: A Rare Case Report

Anti-GQ1b antibodies are considered a hallmark of Miller-Fisher syndrome (MFS), a rare variant of Guillain-Barré syndrome (GBS). The typical clinical presentation of MFS includes ophthalmoplegia, ataxia, and areflexia. Here, we present an unusual case of a 65-year-old man with acute-onset quadriplegia and bulbar weakness resembling locked-in syndrome. Imaging studies did not show structural lesions as a cause for his clinical symptoms. Nerve conduction studies showed severe axonal sensory-motor polyneuropathy. Serum studies were all negative except for a positive anti-GQ1b antibody. He was treated with plasmapheresis as MFS, with a quick improvement in muscle strength. Our case report provided further information on the clinical variation of anti-GQ1b syndrome. Physicians should pay more attention to unusual presentations of anti-GQ1b syndrome because, when it is recognized early with prompt treatment, patients are expected to have a good recovery.

Clinical Features and Differences of Miller Fisher Syndrome in Southern China: Retrospective Analysis of 72 Patients in 13 Provinces of Southern China

BACKGROUND AND PURPOSE

We aimed to determine the clinical features of Miller Fisher syndrome (MFS) in southern China and compare them with those presenting in other countries.

METHODS

We collected the medical records of patients diagnosed with MFS during 2013-2016. We analyzed the age, sex, onset season, precursor events, clinical symptoms and signs, findings of nerve conduction studies (NCS), cerebrospinal fluid (CSF), therapeutic remedies, nadir time, and length of hospital stay of patients with MFS in southern China. We concurrently compared the differences between urban and rural areas and between patients with incomplete ophthalmoplegia (IO) and complete ophthalmoplegia (CO).

RESULTS

The study enrolled 72 patients: 36 from rural areas and 36 from urban areas, and 50 males and 22 females. The mean age at onset was 47.72 years, and 30 (41.7%) and 21 (29.2%) patients developed MFS in spring and winter, respectively. The typical triad of ophthalmoplegia, ataxia, and areflexia was observed in 50 (69.4%) patients. A history of upper respiratory tract infection 1 week before onset was found in 52.8% of the patients, while 5.6% experienced gastrointestinal infections and 48 (73.8%) exhibited albuminocytological dissociation in the CSF study. Only 26 (36.1%) patients presented abnormalities in NCS. Moreover, restricted outward eyeball movement presented in 83.5% of the patients with classic MFS and acute ophthalmoplegia, and bilateral symmetrical ophthalmoplegia presented in 64.2%. With the exception of the higher proportion of NCS abnormalities in urban areas (47.2% vs. 25.0%), urban and rural differences were insignificant regarding sex ratio, age at onset, high-incidence season, precursor events, disease characteristics, and albuminocytological dissociation in the CSF. Furthermore, patients with CO were older than those with IO (64.53±7.69 vs. 43.19±14.40 years [mean±standard deviation], p<0.001).

CONCLUSIONS

The patients with MFS were mostly male and middle-aged, and most presented in winter and (especially) spring. More than half of the patients had clear precursor events, most of which were classic MFS with the typical triad. More than 70% of the patients presented albuminocytological dissociation in the CSF. NCS abnormalities were uncommon in MFS. The age at onset was lower in patients with IO than in patients with CO; bilateral symmetrical extraocular muscle paralysis was the most common symptom, and the external rectus was the most frequently involved muscle.

Norovirus-associated neurological manifestations: summarizing the evidence

Norovirus, a positive-stranded RNA virus, is one of the leading causes of acute gastroenteritis among all age groups worldwide. The neurological manifestations of norovirus are underrecognized, but several wide-spectrum neurological manifestations have been reported among infected individuals in the last few years. Our objective was to summarize the features of norovirus-associated neurological disorders based on the available literature. We used the existing PRISMA consensus statement. Data were collected from PubMed, EMBASE, Web of Science, and Scopus databases up to Jan 30, 2023, using pre-specified searching strategies. Twenty-one articles were selected for the qualitative synthesis. Among these, seven hundred and seventy-four patients with norovirus-associated neurological manifestations were reported. Most cases were seizure episodes, infection-induced encephalopathy, and immune-driven disorders. However, only a few studies have addressed the pathogenesis of norovirus-related neurological complications. The pathogenesis of these manifestations may be mediated by either neurotropism or aberrant immune-mediated injury, or both, depending on the affected system. Our review could help clinicians to recognize these neurological manifestations better and earlier while deepening the understanding of the pathogenesis of this viral infection.

Conformational dynamics and putative substrate extrusion pathways of the N-glycosylated outer membrane factor CmeC from Campylobacter jejuni

The outer membrane factor CmeC of the efflux machinery CmeABC plays an important role in conferring antibiotic and bile resistance to Campylobacter jejuni. Curiously, the protein is N-glycosylated, with the glycans playing a key role in the effective function of this system. In this work we have employed atomistic equilibrium molecular dynamics simulations of CmeC in a representative model of the C. jejuni outer membrane to characterise the dynamics of the protein and its associated glycans. We show that the glycans are more conformationally labile than had previously been thought. The extracellular loops of CmeC visit the open and closed states freely suggesting the absence of a gating mechanism on this side, while the narrow periplasmic entrance remains tightly closed, regulated via coordination to solvated cations. We identify several cation binding sites on the interior surface of the protein. Additionally, we used steered molecular dynamics simulations to elucidate translocation pathways for a bile acid and a macrolide antibiotic. These, and additional equilibrium simulations suggest that the anionic bile acid utilises multivalent cations to climb the ladder of acidic residues that line the interior surface of the protein.

A case of Miller Fisher syndrome with delayed onset peripheral facial nerve palsy after COVID-19 vaccination: a case report

BACKGROUND

To prevent the spread of the novel coronavirus disease 2019 (COVID-19) infection, various vaccines have been developed and used in a large number of people worldwide. One of the most commonly used vaccines is the mRNA vaccine developed by Moderna. Although several studies have shown this vaccine to be safe, the full extent of its side effects has not yet been known. Miller-Fisher syndrome (MFS) is a rare condition that manifests ophthalmoplegia, ataxia, and loss of tendon reflexes. It is a subtype of Guillain-Barré syndrome and an immune-mediated disease related to serum IgG anti-GQ1b antibodies. Several vaccines including those for COVID-19 have been reported to induce MFS. However, there have been no reports of MFS following Moderna COVID-19 vaccine administration.

CASE PRESENTATION

A 70-year-old man was referred to our hospital due to diplopia that manifested 1 week after receiving the second Moderna vaccine dose. The patient presented with restricted abduction of both eyes, mild ataxia, and loss of tendon reflexes. He was diagnosed with MFS based on his neurological findings and detection of serum anti-GQ1b antibodies. The patient was administered intravenous immunoglobulin, and his symptoms gradually improved. Five days after admission, the patient showed peripheral facial paralysis on the right side. This symptom was suggested to be a delayed onset of peripheral facial nerve palsy following MFS that gradually improved by administration of steroids and antiviral drugs.

CONCLUSION

There have been no previous reports of MFS after Moderna COVID-19 vaccination. This case may provide new information about the possible neurological side effects of COVID-19 vaccines.

Weakness in both lower limbs for 1 week and blepharoptosis for 3 days in a boy aged 1 year and 7 months

A boy, aged 1 year and 7 months, was hospitalized due to weakness in both lower limbs and blepharoptosis, which showed progressive aggravation and developed into irregular breathing. Neurological examinations showed lethargy, blepharoptosis, grade 4 muscle strength of both upper limbs, grade 3 muscle strength of both lower limbs, and disappearance of tendon reflex. Laboratory tests revealed albuminocytological dissociation in cerebrospinal fluid, disappearance of H reflex, and positive serum anti-GD1b IgG. The boy was finally diagnosed with Guillain-Barré syndrome (GBS) overlapping with Miller-Fisher syndrome and Bickerstaff brainstem encephalitis. He recovered and was discharged after treatment including immunoglobulin, plasma exchange, and respiratory support. The GBS overlap syndromes in children have strong clinical heterogeneity due to the injury of both peripheral nerve and brainstem, among which anti-GD1b antibody-related GBS overlap syndromes have special clinical manifestations and complex neuroelectrophysiological changes and are thus difficult to diagnose. Nerve conduction velocity tests, especially H reflex test, should be performed for children with weakness in both lower limbs and blepharoptosis.

Clinical and antibodies analysis of anti-GQ1b antibody syndrome: a case series of 15 patients

Objectives

To investigate the clinical manifestations, immunity, laboratory test, treatment and prognosis of patients with anti-GQ1b antibody syndrome in Chongqing, China.

Methods

We reviewed 15 patients with positive anti-ganglioside antibodies in the First Affiliated Hospital of Chongqing Medical University from 2016 to 2019.

Results

Fifteen patients were included in the study (mean age, 54.4 years; age range, 27 to 80 years; 9 men (60%)). Ten patients presented with a history of preinfection, including flu-like syndrome (n = 6, 60%), upper respiratory tract infection (URTI) (n = 3, 30%), and digestive tract infection (GI) (n = 1, 10%). The most common manifestation was ophthalmoplegia (n = 13, 86.67%), followed by weakness (n = 12, 80%), ataxia (n = 11, 73.3%), paresthesia (n = 8, 53.33%) and hypersomnolence (n = 5, 33.33%). All 15 patients underwent antibody testing. Eight patients (53.33%, 7 men (87.5%)) of whom only have positive immunoglobulin G (IgG) against anti-GQ1b antibody while seven (46.67%, 2 men (28.57%)) were positive for multiple anti-ganglioside antibodies apart from anti-GQ1b antibodies. Nine patients (60%) received intravenous immunoglobulin (IVIG) therapy, four (26.67%) received plasma exchange (PE) and two (13.33%) received steroid therapy. Three patients were lost to follow-up at 6 months, 1 patient (6.67%) had persistent back numbness, and the other 11 patients (73.33%) had fully recovered.

Conclusion

The clinical subtype of anti-GQ1b antibody syndrome correlates with the type of anti-ganglioside antibody. Patients who test positive for only anti-GQ1b antibody are more likely to be men. Most patients exhibit a unidirectional course with a good prognosis, but anti-GQ1b antibody syndrome is also associated with a risk of recurrence.

Miller Fisher Syndrome in Patients With Severe Acute Respiratory Syndrome Coronavirus 2 Infection: A Systematic Review

BACKGROUND AND PURPOSE

Miller Fisher syndrome (MFS) is a subtype of Guillain-Barré syndrome characterized by the triad of ophthalmoparesis, areflexia, and ataxia. Although cases of MFS have been associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, no studies have synthesized the clinical characteristics of patients with this condition.

METHODS

In this rapid systematic review, we searched the PubMed database to identify studies on MFS associated with SARS-CoV-2 infection.

RESULTS

This review identified 11 cases, of whom 3 were hospitalized with motor and/or sensory polyneuropathy as the first sign of SARS-CoV-2 infection. SARS-CoV-2 RNA was not detected in analyses of cerebrospinal fluid, suggesting a mechanism of immune-mediated injury rather than direct viral neurotropism. However, antiganglioside antibodies were found in only two of the nine patients tested. It is possible that target antigens other than gangliosides are involved in MFS associated with SARS-CoV-2 infection.

CONCLUSIONS

The present patients exhibited clinical improvement after being treated with intravenous immunoglobulin. Although rare, patients with SARS-CoV-2 infection may present neurological symptoms suggestive of MFS. Early recognition of the MFS clinical triad is essential for the timely initiation of treatment.

Identifying the targets and functions of N-linked protein glycosylation in Campylobacter jejuni

Campylobacter jejuni is a major cause of bacterial gastroenteritis in humans that is primarily associated with the consumption of inadequately prepared poultry products, since the organism is generally thought to be asymptomatic in avian species. Unlike many other microorganisms, C. jejuni is capable of performing extensive post-translational modification (PTM) of proteins by N- and O-linked glycosylation, both of which are required for optimal chicken colonization and human virulence. The biosynthesis and attachment of N-glycans to C. jejuni proteins is encoded by the pgl (protein glycosylation) locus, with the PglB oligosaccharyltransferase (OST) enabling en bloc transfer of a heptasaccharide N-glycan from a lipid carrier in the inner membrane to proteins exposed within the periplasm. Seventy-eight C. jejuni glycoproteins (represented by 134 sites of experimentally verified N-glycosylation) have now been identified, and include inner and outer membrane proteins, periplasmic proteins and lipoproteins, which are generally of poorly defined or unknown function. Despite our extensive knowledge of the targets of this apparently widespread process, we still do not fully understand the role N-glycosylation plays biologically, although several phenotypes, including wild-type stress resistance, biofilm formation, motility and chemotaxis have been related to a functional pgl system. Recent work has described enzymatic processes (nitrate reductase NapAB) and antibiotic efflux (CmeABC) as major targets requiring N-glycan attachment for optimal function, and experimental evidence also points to roles in cell binding via glycan-glycan interactions, protein complex formation and protein stability by conferring protection against host and bacterial proteolytic activity. Here we examine the biochemistry of the N-linked glycosylation system, define its currently known protein targets and discuss evidence for the structural and functional roles of this PTM in individual proteins and globally in C. jejuni pathogenesis.

Guillain-Barré syndrome in Eastern China: A study of 595 patients

BACKGROUND AND PURPOSE

This study aimed to investigate geographical differences in the clinical features of Guillain-Barré syndrome (GBS) between patients from our region in Eastern China and patients from other areas.

METHODS

A total of 595 patients fulfilling the diagnostic criteria ​for GBS or its variants were included from two large hospitals located in Eastern China. Data collection included demographics, antecedent events, clinical presentation and signs, electrophysiological subtypes, treatment, complications during hospitalization, clinical severity at nadir, and outcome at 12 months, and these data were compared to data from a study conducted in Southern China and the Europe/Americas section of the International GBS Outcome Study.

RESULTS

The median (interquartile range) age of patients was 50 (36-61) years, the ratio of men to women was 1.2, and 49% of patients had antecedent events. Patients in our region of Eastern China had pure motor predominant GBS (158/340, 46%) and 30% (103/340) had complications during hospitalization. Patients aged over 60 years had a lower frequency of antecedent infections and single, axonal subtypes, but higher disability scores at entry, nadir, and 12 months. When compared with the Europe/Americas data, our patients had a lower frequency of antecedent infection (46% vs. 63%), cranial nerve involvement (43% vs. 49%), sensory deficits (45% vs. 69%), pain (19% vs. 57%) and mechanical ventilation (11% vs. 17%), but a higher frequency of axonal subtype (35% vs. 6%). There was a higher frequency of patients with antecedent gastroenteritis (16% vs. 8%), mechanical ventilation (11% vs. 8%) and axonal subtypes (35% vs. 19%) in our region in Eastern China than in Southern China.

CONCLUSIONS

Patients with GBS in Eastern China showed significant clinical heterogeneity and differences when compared to other geographic areas.

[A case of Fisher syndrome presented by rapidly progressing bilateral palatoplegia after cytomegalovirus infection]

A 35-year-old male developed sensory abnormality of peripheral limbs and oral cavity after prior infection with diarrhea and cold symptoms. Hyperrhinolalia, nasopharyngeal reflux, double vision, and wobbling in walking rapidly progressed. Neurological examination revealed palatoplegia, omnidirectional ophthalmoplegia, hyperreflexia, sensory disturbance of extremities, and truncal and limb ataxia due to decreased deep sensation. A peripheral nerve conduction study found a slight decrease in sensory nerve action potential of the median nerve and a decrease in F wave frequency of the median nerve. Serum IgM-CMV antibody was positive on admission. After IVIg therapy, palatoplegia and ataxia markedly improved. In this case, GalNAc-GD1a and GM2 antibodies, which are often detected after CMV infection, were positive in addition to the GT1a and GQ1b antibodies, and it was assumed that these findings were associated with the palatoplegia, which is included in cranial nerve palsy. Pathophysiologically, the present case is considered to be an overlap with acute oropharyngeal palsy (AOP), which is a rare subtype of Guillain-Barre syndrome, and Fisher syndrome (FS). The clinical aspects of the present case suggest a continuous spectrum between AOP and FS.

Mother and son cases of Bickerstaff's brainstem encephalitis and fisher syndrome with serum anti-GQ1b IgG antibodies: a case report

Background

Bickerstaff’s brainstem encephalitis (BBE) and Fisher syndrome (FS) are immune-mediated diseases associated with anti-ganglioside antibodies, specifically the anti-GQ1b IgG antibody. These two diseases potentially lie on a continuous spectrum with Guillain-Barré Syndrome (GBS). There are some reports of family cases of GBS and fewer of FS. However, there are no reports of family cases of BBE and FS.

Case presentation

We report a familial case of an 18-year-old son who had BBE and his 52-year-old mother diagnosed with FS within 10 days. The son showed impaired consciousness 1 week after presenting with upper respiratory symptoms and was brought to our hospital by his mother. He showed decreased tendon reflexes, limb ataxia, albuminocytologic dissociation in his spinal fluid, and positive serum anti-GQ1b antibodies. Haemophilus influenzae was cultured from his sputum. He was diagnosed with BBE and treated with intravenous immunoglobulin (IVIg) therapy, which led to an improvement in symptoms. The mother presented with upper respiratory symptoms 3 days after her son was hospitalized. Seven days later, she was admitted to the hospital with diplopia due to limited abduction of the left eye. She showed mild ataxia and decreased tendon reflexes. Her blood was positive for anti-GQ1b antibodies. She was diagnosed with FS and treated with IVIg, which also led to symptomatic improvement.

Conclusions

There are no previous reports of familial cases of BBE and FS; therefore, this valuable case may contribute to the elucidation of the relationship between genetic predisposition and the pathogenesis of BBE and FS.

Clinical Characterization of Anti-GQ1b Antibody Syndrome in Childhood

Objective: To delineate the comprehensive clinical features of anti-GQ1b antibody syndrome in childhood. Methods: The clinical data of children diagnosed with anti-GQ1b antibody syndrome at two Chinese tertiary pediatric neurology centers were collected and analyzed. We also conducted a systematic literature review on anti-GQ1b antibody syndrome in children. Results: This study included 78 children with anti-GQ1b antibody syndrome, consisting of 12 previously unreported cases from the two Chinese centers. The median onset age was 10 years (range, 2-18 years). The most common phenotype was acute ophthalmoparesis (32%), followed by classic Miller Fisher syndrome (15%), and Bickerstaff brainstem encephalitis (12%). External ophthalmoplegia (48%), sensory disturbance (9%), and bulbar palsy (9%) were the three most frequent onset symptom manifestations. Brain or spinal lesions on MRI and abnormal recordings by nerve conduction study were present in 18% (12/68) and 60% (27/45) of cases, respectively. There was CSF albuminocytologic dissociation in 34% of the patients (23/68). IV immunoglobulin alone or combined with steroids or plasma exchange was administered to 58% of patients (42/72). We did not find a significant correlation between early improvement up to 3 months and age onset and phenotype. All patients showed different degrees of recovery, and 81% (57/70) had complete recovery within 1 year. Conclusions: Acute ophthalmoparesis and classic Miller Fisher syndrome are the most common phenotypes of anti-GQ1b antibody syndrome in childhood. The majority of patients show good response to immunotherapy and have favorable prognosis.

Surge of Miller Fisher variant and Guillain-Barré syndrome in two downtown Los Angeles community teaching hospitals

Guillain-Barré syndrome (GBS) and Miller Fisher variant (MFv) cases spiked threefold in Los Angeles, with a high proportion of MFv cases. MFv is underdiagnosed when accompanying neurological symptoms are mild. This report emphasizes the seasonality of GBS and its relation to ganglioside antibodies.

Acute ophthalmoplegia in a patient with anti-GQ1b antibody and chronic facial diplegia

A 56-year-old man with a remote history of bilateral recurrent facial palsies presented with a week of ophthalmoplegia with intact deep tendon reflexes and lack of ataxia, cerebrospinal fluid with albuminocytologic dissociation and elevated serum anti-ganglioside Q1b (GQ1b) IgG antibody. We diagnosed the patient with acute ophthalmoplegia without ataxia, a condition under the spectrum of anti-GQ1b antibody syndromes which also includes Miller Fisher syndrome. Given the rarity of recurrent facial palsies and anti-GQ1b antibody syndromes as well as reports associating facial palsies and this syndrome, we suggest that our case may be an unusual presentation of an anti-GQ1b antibody syndrome beginning with recurrent facial palsies several years prior to ophthalmoplegia. Prior studies of human nerves provide insight into the pathophysiology, including ganglioside distribution and cross-reactivities underlying the heterogeneity of anti-GQ1b antibody syndromes. This report may expand the differential diagnosis in patients with recurrent facial palsies and broaden the phenotype of anti-GQ1b syndromes.

Neurological Consequences of 2019-nCoV Infection: A Comprehensive Literature Review

First identified in November 2019 in Hubei Province, the coronavirus disease of 2019 (COVID-19) caused by SARS-CoV-2 soon spread worldwide to become a global health pandemic. The COVID-19 preferentially damages the respiratory system that produces symptoms such as fever, cough, and shortness of breath. However, the infection often tends to disseminate to involve various organ systems. Recent evidence indicates that SARS-CoV-2 can cause significant neurological damage and resultant neurological symptoms and complications. Here, we provide a comprehensive and thorough review of original articles, case reports, and case series to delineate the possible mechanisms of nervous system invasion and damage by SARS-CoV-2 and subsequent consequences. We divided the neurological manifestations into three categories: (1) Central Nervous System involvement, (2) Peripheral Nervous System manifestations, and (3) Skeletal Muscle Injury. Headache and dizziness were found to be the most prevalent symptoms followed by impaired consciousness. Among the symptoms indicating peripheral nervous system invasion, anosmia and dysgeusia were commonly reported. Skeletal muscle injury predominantly presents as myalgia. In addition, encephalitis, myelitis, cerebrovascular disease, Guillain-Barre syndrome, and Miller Fischer syndrome were among the commonly noted complications. We also emphasized the association of pre-existing comorbidities with neurological manifestations. The aim of this review is to provide a deeper understanding of the potential neurological implications to help neurologists have a high index of clinical suspicion allowing them to manage the patient appropriately.

Miller Fisher syndrome and polyneuritis cranialis in COVID-19

OBJECTIVE

To report 2 patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) who presented acutely with Miller Fisher syndrome and polyneuritis cranialis, respectively.

METHODS

Patient data were obtained from medical records from the University Hospital "Príncipe de Asturias," Alcalá de Henares, and the University Hospital "12 de Octubre," Madrid, Spain.

RESULTS

A 50-year-old man presented with anosmia, ageusia, right internuclear ophthalmoparesis, right fascicular oculomotor palsy, ataxia, areflexia, albuminocytologic dissociation, and positive testing for anti-GD1b-immunoglobulin G antibody. Five days previously, he had developed a cough, malaise, headache, low back pain, and fever. A 39-year-old man presented with ageusia, bilateral abducens palsy, areflexia, and albuminocytologic dissociation. Three days previously, he had developed diarrhea, a low-grade fever, and poor general condition. Oropharyngeal swab test for SARS-CoV-2 by qualitative real-time reverse transcriptase PCR assay was positive in both patients and negative in the CSF. The first patient was treated with IV immunoglobulin and the second with acetaminophen. Two weeks later, both patients made a complete neurologic recovery, except for residual anosmia and ageusia in the first case.

CONCLUSIONS

Our 2 cases highlight the rare occurrence of Miller Fisher syndrome and polyneuritis cranialis during the coronavirus disease 2019 (COVID-19) pandemic. These neurologic manifestations may occur because of an aberrant immune response to COVID-19. The full clinical spectrum of neurologic symptoms in patients with COVID-19 remains to be characterized.