Bickerstaff's Encephalitis Research Articles

A case of Bickerstaff brainstem encephalitis successfully treated with intravenous immunoglobulin and methylprednisolone after unsuccessful immunoadsorption plasmapheresis

Bickerstaff brainstem encephalitis (BBE) is a rare post-infectious neurological syndrome for which an effective treatment strategy has not been established. Here, we report a case of a 71-year-old male who suffered from an upper respiratory tract infection, and 7 days later, developed numbness of the bilateral upper and lower limbs, unsteady gait and dysarthria. Brain magnetic resonance imaging was normal, nerve conduction study and cerebral spinal fluid analysis were nonspecific. Based on the clinical features, we tentatively diagnosed Guillain-Barré syndrome and started immunoadsorption plasmapheresis. However, consciousness progressively declined to coma level within 10 days. Electroencephalogram showed diffuse slowing, and auditory evoked brainstem response (ABR) demonstrated absence of waves II, III and V. Serum anti-GQ1b IgG autoantibody and anti-GM1b IgG autoantibody were negative. Subsequently, we diagnosed BBE, and clinical symptoms resolved after treatment with intravenous immunoglobulin and methyllprednisolone. On day 62, neurological symptoms were remarkably alleviated with an improvement in ABR. Our observations suggest that immunoadsorption plasmapheresis should be used only when anti-ganglioside antibodies are detected. Combination therapy with intravenous immunoglobulin and methylprednisolone or plasma exchange is recommended as initial therapy.

Acute ataxic neuropathy with hyperreflexia

Dear Editor, The ataxic form of Guillain-Barre syndrome (GBS), characterized by acute profound ataxia with negative Romberg sign and no (or minimal) ophthalmoplegia [1], is considered as an incomplete form of Fisher syndrome [2]. However, its nosological relationship to acute sensory ataxic neuropathy was not discussed [3]. A recent comprehensive study shows how ataxic GBS and acute sensory ataxic neuropathy share similar clinical and laboratory features, forming a continuous spectrum under the term: acute ataxic neuropathy without ophthalmoplegia (AAN) [4]. AAN typically presents with areflexia or hyporeflexia. Preserved or brisk reflexes are seen in GBS or Bickerstaff brainstem encephalitis [5, 6], but not in AAN. We report the first case of AAN with hyperreflexia. A 45-year-old male developed unsteady gait, 5 days after experiencing fever and sore throat. He had no prior medical history and abstained from alcohol. On day 2, he developed diplopia at all extremes of gaze, with left hand and foot numbness, and a broad-based gait. He demonstrated bilateral dysmetria, and abnormal left heel-shin test. Eye pursuit, vertical and horizontal eye movements were full, except for convergence. He had no nystagmus. Pupils were 5 mm bilaterally with normal light and accommodation reflexes. Cranial nerves were otherwise intact with no facial or oropharyngeal weakness. Limb power and tone were normal. He had hyperreflexia in all 4 limbs, but with normal jaw jerk and down-going plantar responses. Despite complaining of left-sided distal dysesthesias, objective sensory testing of all modalities was normal, other than an abnormal Romberg’s test. There was no autonomic involvement. His brain MRI showed no abnormalities or Wernicke’s encephalopathy. MRI spine had no myelopathy or ventral nerve root enhancement. His vitamin B1 levels were normal and lumbar puncture on day 3 was slightly traumatic with 181 red blood cells/lL, protein 1.2 g/dL (normal, \0.6 g/dL) and 45 cells/lL of predominantly lymphocytic white blood cells. We diagnosed AAN with unusually brisk reflexes. As he was ambulatory, we treated him conservatively. Median, ulnar, tibial and peroneal nerve conduction studies on day 4 showed normal amplitudes of the compound motor action potentials and normal distal motor latencies. Sensory nerve action potential amplitudes and latencies were normal. F-waves had normal latencies and were not dispersed. However, his somatosensory evoked potentials, recording from bilateral median and posterior tibial nerves, showed prolonged cerebral evoked N18 and P37 latencies (Table 1). Nerve conduction studies, including peripheral sensory nerve potentials on day 10 remained normal, whereas N18 and P37 latencies normalized by day 15. Anti-GQ1b antibodies were absent, but IgG anti-GM1b antibodies were positive in his serum. Upon discharge on day 12, eye convergence and gait had improved while hyperreflexia and left-sided limb dysmetria remained. His dysesthesia had resolved but Romberg’s test remained positive. He remained alert throughout the illness and his reflexes normalized on day 45. L. L. L. Yeo K. Ng Division of Neurology, Department of Medicine, National University Hospital, Singapore, Singapore

Acute Complex Neuroplegia and Ophthalmoplegia Associated with Anti-GQ1b Antibodies

A 24-year-old gentleman presented with a history of severe throbbing headache preceded by sore throat. He was noted to have a nasal twang and dysphagia. He progressively developed weakness of all four limbs associated with ophthalmoplegia. He, subsequently, had to be intubated and ventilated in view of the involvement of the respiratory muscles. His anti-GQ1b antibodies were positive and the diagnosis of Bickerstaff brainstem encephalitis associated with Miller Fisher Syndrome overlapping with Guillain-Barre syndrome was confirmed. He was treated with intravenous Immunoglobulins 0.4 gm/kg/day for 5 days which resulted in a gradual recovery from his neurologic weakness.

G.P.74 Clinical aspects of presynaptic neuromuscular transmission defect in anti-GQ1b IgG antibody-related disorders

Abstract Guillain–Barre syndrome (GBS), Miller Fisher syndrome (MFS) and Bickerstaff’s brainstem encephalitis (BBE) are immune-mediated disorders with overlapping clinical features, whereby anti-GQ1b IgG antibody is detected in variable frequencies. In vitro studies of MFS have demonstrated anti-GQ1b IgG antibody-mediated presynaptic damage at the neuromuscular junction. Previous studies have provided electrophysiological evidence of presynaptic neuromuscular transmission defect in anti-GQ1b positive MFS patients, which persisted up to 3 months from initial presentation. In this study, we compared incremental responses antibody-positive MFS and BBE (Group 1) with antibody-negative GBS and MFS variants (Group 2) using repetitive nerve stimulation (RNS) as an electrophysiological measurement of presynaptic neuromuscular transmission defect. With 20 Hz RNS, Group 1 showed significantly greater incremental responses compared to Group 2 (t-test, p = 0.0006). With 50 Hz RNS, Group 1 also showed significantly greater incremental responses compared to Group 2 (t-test, p = 0.002). Repeat studies at 6 months demonstrated return of increments to within normal limits in all three patients in Group 1. There was significant correlation of the initial increments (mean of 20 Hz and 50 Hz) and anti-GQ1b IgG antibody titer (Pearson’s correlation coefficient r = 0.76, p = 0.011). In addition to MFS, we have also shown that presynaptic dysfunction can occur in BBE. To this end, incremental responses in upper limb muscles may serve as surrogate markers for NM transmission defect in these disorders. As immunotherapy is the mainstay of treatment in these conditions, our findings of presynaptic neuromuscular transmission defect may serve as a potential parameter in selecting patients for future therapeutic trials.

Severe Bickerstaff's encephalitis treated with Rituximab: Serum and CSF GQ1b antibodies

Bickerstaff's encephalitis is a syndrome of ophthalmoplegia, ataxia and impaired consciousness commonly associated with serum GQ1b antibodies. We describe a patient with seropositive Bickerstaff's encephalitis who did not respond either to plasma exchange or intravenous immunoglobulin but recovered following adjunct treatment with the anti-CD 20 monoclonal antibody, Rituximab. There was a concomitant reduction in serum GQ1b antibodies associated with improvement. Interestingly, GQ1b antibody was also detected in CSF. These findings have potentially significant clinical and immunopathological implications.

Nationwide survey of patients in Japan with Bickerstaff brainstem encephalitis: epidemiological and clinical characteristics

BackgroudInformation regarding the epidemiological background of Bickerstaff brainstem encephalitis (BBE) is limited.MethodsWe conducted a nationwide survey of BBE in the Japanese population in two steps: the first aimed to identify...

Non-demyelinating, reversible conduction failure in Fisher syndrome and related disorders

BackgroundIgG anti-GQ1b antibodies are associated with Fisher syndrome (FS), Bickerstaff brainstem encephalitis (BBE), acute ophthalmoparesis and overlap of FS or BBE with Guillain–Barré syndrome (GBS) (FS/GBS or BBE/GBS). It has...

Clinical Variants of Guillain-Barré Syndrome in Children

Guillain-Barré syndrome is characterized by acute progressive weakness, areflexia, and maximal motor disability that occur within 4 weeks of onset. Various clinical subtypes have been described since the original description of the syndrome. This study aimed to identify characteristics of clinical variants of Guillain-Barré syndrome through retrospective review of cases in Chang Gung Children's Hospital from 2000-2010. Forty-three Guillain-Barré syndrome patients were evaluated based on clinical presentations and an electrodiagnostic study. The most frequent variant of Guillain-Barré syndrome was demyelinating polyneuropathy (67.4%), followed by acute axonal neuropathy (7.0%), Miller Fisher syndrome (7.0%), Bickerstaff brainstem encephalitis (7.0%), pharyngo-cervical-brachial variant (4.7%), and polyneuritis cranialis (4.7%). Follow-up revealed that 35 recovered satisfactorily, eight were persistently disabled, and none died during hospitalization. At the earliest stage, differentiating clinical variants from typical Guillain-Barré syndrome was difficult. Children with clinical variants of Guillain-Barré syndrome are more likely to manifest rapid onset from disease onset to nadir, increasing the severity of disability, cranial nerve involvement, urine incontinence, respiratory impairment, and need for ventilator support than in typical Guillain-Barré syndrome.

Bickerstaff’s Brainstem Encephalitis Presenting to the ICU

Bickerstaff's brainstem encephalitis continues to pose a diagnostic and treatment challenge since the original descriptions by Bickerstaff and Miller-Fisher. The clinical syndrome overlaps with AIDP and MFS, but is accompanied by decreased level of consciousness not attributable to other causes, and the variable presence of long-tract signs. The methods in this study include the case presentation with autopsy findings of an elderly male presented with progressive weakness and impairment of consciousness and the literature review. Examination revealed areflexia and loss of most brainstem reflexes. Some improvement occurred after several weeks in the ICU, prior to death from pulmonary embolism. Pathologic specimens were similar to others in the literature, with inflammatory changes in nerve roots and brainstem. The above findings led us to conclude that Bickerstaff's brainstem encephalitis remains a clinical diagnosis despite advances in electrophysiologic testing and neuroimaging. BBE likely represents part of a spectrum, overlapping with AIDP and MFS. Immunomodulation may be helpful in shortening the clinical course.

Effect of Sera from Bickerstaff Brainstem Encephalitis and Miller Fisher Syndrome Patients Against Human Blood-Brain Barrier and Blood-Nerve Barrier In Vitro Models (P06.141)

Objective: Antibody against GQ1b is frequently detected in Bickerstaff brainstem encephalitis (BBE) and Miller Fisher syndrome (MFS) and has been considered to be pathogenically important in the development of these two disorders; however, the clinical manifestations of there two disorders are obviously different. We hypothesized that there phenotypic differences may be derived from the difference of blood-brain barrier (BBB)/ blood-nerve barrier(BNB) breakdown. Background We demonstrated the effects of sera from patients with BBE and MFS on the impairment of BBB or BNB function and clarified the roles of humoral factor such as Matrix metalloproteinases(MMP) in the destruction of BBB or BNB. Design/Methods: Both human BBB and BNB-derived endothelial cell lines were recently developed in Yamaguchi University, named TY10 and PnMECs. We evaluated transendothelial electrical resistance (TEER), the amount of tight junction proteins including claudin-5 and occludin, and the amount of MMP including MMP-9 and MMP-2 by western blotting in TY10 and PnMECs after the exposure of the patients9 sera. Results: The amount of claudin-5 protein in TY10, not in PnMECs, decreased after exposure of BBE sera. TEER of TY10 also decreased after application of BBE sera. Sera from MFS patients had no effect in these experiments. The amount of MMP-9 and MMP-2 protein in TY10 increased after exposure of BBE sera. Conclusions: Only sera from BBE patients disrupt BBB. This may partially explain the phenotypic defferences between BBE and MFS. BBE sera break BBB, possibly via autocrine secretion of MMP-9 and MMP-2 from BBB-composing endothelial cells. Disclosure: Dr. Saito has nothing to disclose. Dr. Shimizu has nothing to disclose. Dr. Koga has nothing to disclose. Dr. Sano has nothing to disclose. Dr. Haruki has nothing to disclose. Dr. Maeda has nothing to disclose. Dr. Abe has nothing to disclose. Dr. Tasaki has nothing to disclose. Dr. Suzuki has nothing to disclose. Dr. Kusunoki has nothing to disclose. Dr. Mizusawa has received personal compensation for activities with Tanabemitsubishi Co and Sanofi-Aventis Co. Dr. Mizusawa has received personal compensation in an editorial capacity for No to Shinkei and Clinical Neuroscience. Dr. Kanda has nothing to disclose.

Neuropathy, Encephalopathy, Lambert-Eaton Myasthenic Syndrome and Myasthenia Gravis in a Non-Small Cell Neuroendocrine Tumor of the Lung - An Interesting Paraneoplastic Syndrome: Case Report and Review of Literature. (NELM Syndrome) (P04.094)

Objective: To report a case of Neuropathy, Encephalopathy, Myasthenia Gravis and Lambert Eaton Myasthenic Syndrome in a patient with neuroendocrine lung cancer. Background Case reports of combined Myasthenia Gravis(MG) and Lambert-Eaton Myasthenic Syndrome(LEMS) have been reported with small cell lung cancer but never been reported in Large Cell NeuroEndocrine Cancer(LCNEC) in English literature. We describe the first case of MG, LEMS and demyelinating neuropathy in a patient with LCNEC of lung and response to intravenous immunoglobulin (IVIG) treatment. Design/Methods: case report and review of literature. Results: A 64-year-female with LCNEC(stage-1A) status post wedge resection presented with one week history of encephalopathy, diplopia, generalized weakness and paresthesia. She had autonomic instability reflected by wide fluctuation in her blood pressure. Examination showed external ophthalmoplegia, facial diplegia and proximal 2/5, distal 4/5 strength with areflexia. She was intubated secondary to neuromuscular weakness. EEG showed moderate encephalopathy. MRI of brain and cerebrospinal fluid analysis were unremarkable. Electrophysiological studies revealed severe sensorimotor demyelinating polyneuropathy. Repetitive nerve stimulation showed decremental response of > 20%. She also had positive acetylcholine receptor binding antibody and voltage gated calcium channel antibody. An extensive paraneoplastic panel was negative. Anti-Gq1b antibody was negative. Immunoperoxidase staining of lung biopsy was positive for CD-15, TTF-1, CK-7 and CAM 6.2. Patient received 2 courses of IVIG 2 gm/ kg with rapid recovery. Follow- up showed mild right upper extremity weakness and ataxia. She did not have any recurrence of symptoms in a 2 year follow- up. Conclusions: This is an unusual paraneoplastic manifestation of LCNEC lung cancer where patient presented with features of MG, LEMS and demyelinating neuropathy at the same time with very good response to IVIG. A combination of encephalopathy, ophthalmoplegia, areflexia and demyelinating neuropathy also suggests Bickerstaff Encephalitis(BE) despite negative anti-Gq1b antibody(32% negative anti-Gq1b antibody in BE). Multiple antibodies targeting different receptors may underlie pathology. Disclosure: Dr. Neelam has nothing to disclose. Dr. Lim has nothing to disclose. Dr. Singh has nothing to disclose.

Analysis ofCampylobacter jejuniisolates of various sources for loci associated with Guillain-Barré syndrome

Campylobacter jejuni is a major cause of the Guillain-Barré syndrome (GBS) and related diseases. These autoimmune diseases are caused by antibodies cross-reacting with the peripheral (GBS) and central neural tissue (Miller Fisher syndrome - MFS, Bicker-staff's brainstem encephalitis - BBE), leading to acute polyneuropathy. Recently, specific gene loci in C. jejuni have been distinguished which are associated with the onset of GBS, despite a molecular or phenotypic clustering. In this study, we used PCR to analyse C. jejuni isolates of different origin (i.e. bovine, poultry, human) for these genes. A total of 196 isolates were tested for cst-II and neuA. Of these, 101 isolates harboured the cst-II locus and 102 the neuA locus. Eighty-six isolates (44%) hold both genes. The frequency of cst-II in different sources of isolates of bovine, poultry and human isolates did not vary significantly (52, 50 and 52%, respectively). In contrast, the neuA locus was less often found in poultry isolates. Two human strains - from a family outbreak of campylobacteriosis (in 1989 in Austria) in which one person developed MFS - harboured both genes. Thus, although only one in more than 3000 patients with Campylobacter-associated enteritis develop GBS, about half of Campylobacter jejuni strains found in different environments are possibly able to cause GBS. These strains almost equally distributed in bovine, poultry and human isolates. Our results suggest that isolates associated with GBS are not selected by environmental or host-specific factors. Accordingly, this study indicates that host factors such as humoral and cellular immunity are possibly responsible for the development of these autoimmune diseases.

Encephalitis in the Pediatric Population

1. Stephen J. Falchek, MD* 1. *Division of Pediatric Neurology, Alfred I. duPont Hospital for Children/Thomas Jefferson University, Wilmington, DE, and Philadelphia, PA. * Abbreviations: ADEM: : acute disseminated encephalomyelitis CEP: : California Encephalitis Project CNS: : central nervous system CPP: : cerebral perfusion pressure CSF: : cerebrospinal fluid HSV: : herpes simplex virus IVIG: : intravenous immune globulin MS: : multiple sclerosis PCR: : polymerase chain reaction WNV: : West Nile virus Management of encephalitis, which can be fatal, requires understanding of a broad range of causative agents, pathophysiologic mechanisms, clinical syndromes, and outcomes. After completing this article, readers should be able to: 1. Know the many causes of encephalitis, including infectious, parainfectious, and noninfectious disorders. 2. Recognize the clinical features of encephalitis. 3. Be able to conduct a diagnostic investigation of a patient with encephalitis by using clinical and laboratory criteria. 4. Know the anticipated clinical course of different types of encephalitis. 5. Be familiar with the modalities used to treat encephalitis. 6. Understand the factors that influence the outcome in a patient who has encephalitis. The broad definition of the term “encephalitis,” that is, inflammation of the brain , necessitates acknowledgment of the enormous inclusivity of the topic. The most common interpretation of the term implies a direct invasion of the brain by an infectious pathogen, most commonly, viral, fungal, or parasitic. The topic also includes examples of meningitis mediated by bacteria or other agents, which can produce extrameningeal symptoms such as lethargy or seizures, in which case, the combined term “meningoencephalitis” is used. There are also many examples of encephalitis not due to direct central nervous system (CNS) infections. Inflammatory processes due to an acute or chronic illness can result in an acute immune-mediated encephalitis, such as acute disseminated encephalomyelitis (ADEM), lupus cerebritis, and paraneoplastic syndromes. Agents or conditions that produce slowly progressive CNS symptoms, such as tertiary syphilis or “slow viruses” (the prion protein encephalopathies), also are considered examples of encephalitis. Table 1 lists only a limited number of the many pathogens and pathologic conditions that can cause either acute or subacute encephalitis. In this discussion, …

除皮質硬直姿勢を呈したspindle comaから完全回復したBickerstaff脳幹脳炎の若年男性の1例

A 25-years-old man experienced fever and diarrhea. Ten days later he noticed difficulty walking (day 1). On admission neurological examination revealed lethargy, dysarthria and weakness of limbs. Oculocephalic response was not be elicited and extensor toe signs were positive. In spite of treatment with aciclovir and methylprednisolone, he continued to show progressive deterioration developing to coma with decorticate posture. Autonomic symptoms (hyperhidrosis, hypersalivation and fever) and groaning were observed. Brain magnetic resonance image and brainstem evoked potential presented no abnormality, but electroencephalographic study showed a spindle pattern indicating spindle coma. Laboratory tests including cerebrospinal fluids showed no specific results. High-dose immunoglobulin was administered from day 6, and his consciousness level improved. External ophthalomoplegia and ataxic gait were observed after he became more alert. Because he had IgG type anti-GQ1b antibodies in the serum, a diagnosis was made of Bickerstaff's brainstem encephalitis (BBE). Six months after discharge he had complete resolution of his symptoms. This is the first report of spindle coma observed in a case of serologically confirmed BBE.

Fisher症候群に多発性脳神経障害と脳波異常を合併した1例

A 69-year-old woman was admitted because of unconsciousness and multiple cranial neuropathy. She had suffered diarrhea 2 weeks previously. On examination, she was noted to have total external and internal ophthalmoplegia, bilateral facial palsy, dysphagia, dysarthria, neck weakness, distal motor weakness of all limbs, and ataxia. She had also presented with hyporeflexia and hypoesthesia, but with a bilateral pyramidal tract sign. A study of her cerebrospinal fluid revealed albuminocytologic dissociation, and nerve conduction study revealed demyelination of her peripheral nerves. Moreover, electroencephalography findings were abnormal and anti-GQ1b antibody was positive. We diagnosed Fisher syndrome with Guillain-Barré syndrome and Bickerstaff brainstem encephalitis. We administered intravenous immunoglobulin treatment for 5 days and her symptoms gradually improved. However, her external ophthalmoplegia continued for several months.

Guillain–Barré syndrome and anti-ganglioside antibodies: a clinician-scientist’s journey

Guillain–Barré syndrome (GBS) is the most frequent cause of acute flaccid paralysis. Having seen my first GBS patient in 1989, I have since then dedicated my time in research towards understanding the pathogenesis of GBS. Along with several colleagues, we identified IgG autoantibodies against ganglioside GM1 in two patients with GBS subsequent to Campylobacter jejuni enteritis. We proceeded to demonstrate molecular mimicry between GM1 and bacterial lipo-oligosaccharide of C. jejuni isolated from a patient with GBS. Our group then established a disease model for GBS by sensitization with GM1 or GM1-like lipo-oligosaccharide. With this, a new paradigm that carbohydrate mimicry can cause autoimmune disorders was demonstrated, making GBS the first proof of molecular mimicry in autoimmune disease. Patients with Fisher syndrome, characterized by ophthalmoplegia and ataxia, can develop the disease after an infection by C. jejuni. We showed that the genetic polymorphism of C. jejuni sialyltransferase, an enzyme essential to the biosynthesis of ganglioside-like lipo-oligosaccharides determines whether patients develop GBS or Fisher syndrome. This introduces another paradigm that microbial genetic polymorphism can determine the clinical phenotype of human autoimmune diseases. Similarities between the clinical presentation of Fisher syndrome and Bickerstaff brainstem encephalitis have caused debate as to whether they are in fact the same disease. We demonstrated that IgG anti-GQ1b antibodies were common to both, suggesting that they are part of the same disease spectrum. We followed this work by clarifying the nosological relationship between the various clinical presentations within the anti-GQ1b antibody syndrome. In this review, I wanted to share my journey from being a clinician to a clinician-scientist in the hopes of inspiring younger clinicians to follow a similar path.

Unusual manifestations in two cases of necrotizing myopathy associated with SRP antibodies

Anti-SRP (signal recognition particle) positive necrotizing myopathy is commonly not associated with neoplasms. We demonstrate two histologically confirmed cases with unusual manifestations of anti-SRP positive necrotizing myopathy. A 65-year-old man presented with rapidly progressing weakness and mild difficulties in swallowing and speaking. Screening for underlying disorders revealed a moderately differentiated renal adenocarcinoma. The muscular symptoms partially improved after tumor nephrectomy and prednisone treatment. However, the patient developed pulmonary metastases and died of the sequelae of pneumonia 11 months after the diagnosis of renal cancer. The second patient developed rapidly complete external ophthalmoplegia, severe bulbar dysarthrophonia and dysphagia, bilateral facial palsy, loss of patellar and ankle jerk reflexes, and severe symmetrical tetraparesis of both proximal and distal muscles. CSF showed mildly increased protein levels, neurography axonal impairment of motor nerves. Screening revealed no evidence for infections, ganglioside antibodies, and carcinoma. MRI was normal. The disease course suggested an overlap syndrome of Miller-Fisher-syndrome, axonal Guillain-Barre-syndrome and Bickerstaff brainstem encephalitis. In conclusion SRP antibodies might be found in necrotizing myopathies associated with autoimmune mediated overlap syndromes and neoplasms. The pathomechanism is not clear. Any otherwise unexplained evidence of necrotizing myopathy should prompt the screening for SRP antibodies.

Encefalitis de Bickerstaff, síndrome o espectro de Fisher Bickerstaff, reporte de dos casos

La encefalitis de Bickerstaff es una entidad infrecuente de origen posinfeccioso, de presentación grave y con un curso clínico generalmente benigno, cuya diferenciación con el síndrome de Fisher aún no es clara y su asociación con el síndrome de Guillain - Barré está ya establecida. Presentamos dos casos atendidos en el Hospital Universitario San Ignacio.

Miller Fisher syndrome: brief overview and update with a focus on electrophysiological findings

Miller Fisher syndrome (MFS), a variant of the Guillain-Barré syndrome (GBS), is characterized by ophthalmoplegia, ataxia, and areflexia. The annual incidence is around one patient per one million population. The antiganglioside anti-GQ1b IgG antibody has a role in the pathogenesis of the syndrome, especially of ophthalmoplegia. The presence of this antibody in the serum can be identified in over 80% of the patients, peaking in the first week, whereas albuminocytological dissociation in the cerebrospinal fluid (CSF) appears later. The most consistent electrophysiological findings in MFS are reduced sensory nerve action potentials and absent H reflexes. More variability is seen with F waves and various investigations involving cranial structures. Although there are usually no abnormalities in MFS by routine neuroimaging, in a few cases, contrast enhancement of nerve roots and signs of central nervous system involvement were described supporting the hypothesis of an anti-GQ1b-syndrome, a continuum involving GBS, MFS, and Bickerstaff's brainstem encephalitis. Owing to the lack of randomized trials, treatments used for GBS (intravenous immunoglobulin and plasmapheresis) are usually applied, although from retrospective analyses, the outcome was similar between treated and untreated subjects. The outcome of MFS is usually good with case fatality of < 5%. In the few autopsy cases, macroscopic abnormalities were generally not seen in the nervous system. Microscopic examination of the peripheral nervous system (including cranial nerves) showed segmental demyelination with minimal perivascular infiltration with normal spinal cord and brain stem.

Bickerstaff’s brainstem encephalitis: case report and Tc99m brain SPECT findings

A 21-year-old healthy female suffered from an upper respiratory tract infection and 2days later developed diplopia, unsteady gait, dysarthria and a profound disturbance of consciousness with rapid development of coma. Brain MRI and Tc99m brain perfusion SPECT, EEG, neurophysiological tests and CSF analysis results were unspecific. The detection of serum anti-GQ1b IgG autoantibodies at high titre led to the diagnosis of Bickerstaff's brainstem encephalitis (BBE). Clinical symptoms resolved after treatment with plasma exchange and the outcome was good. Brain MRI was normal, and Tc99m brain perfusion SPECT demonstrated hypoperfusion of the whole cerebral hemispheres and basal ganglia with relative sparing of the thalami and the brainstem. Similar to brain MRI, the sensitivity of Tc99m brain perfusion SPECT in detecting brainstem lesions in typical BBE patients seems to be low.