Electrodiagnostic subtyping in Guillain-Barré syndrome patients in the International Guillain-Barré Outcome Study.

BACKGROUND AND PURPOSE: Various electrodiagnostic criteria have been developed in Guillain-Barré syndrome (GBS). Their performance in a broad representation of GBS patients has not been evaluated. Motor conduction data from the International GBS Outcome Study (IGOS) cohort were used to compare two widely used criterion sets and relate these to diagnostic amyotrophic lateral sclerosis criteria. METHODS: From the first 1500 patients in IGOS, nerve conduction studies from 1137 (75.8%) were available for the current study. These patients were classified according to nerve conduction studies criteria proposed by Hadden and Rajabally. RESULTS: Of the 1137 studies, 68.3% (N = 777) were classified identically according to criteria by Hadden and Rajabally: 111 (9.8%) axonal, 366 (32.2%) demyelinating, 195 (17.2%) equivocal, 35 (3.1%) inexcitable and 70 (6.2%) normal. Thus, 360 studies (31.7%) were classified differently. The areas of differences were as follows: 155 studies (13.6%) classified as demyelinating by Hadden and axonal by Rajabally; 122 studies (10.7%) classified as demyelinating by Hadden and equivocal by Rajabally; and 75 studies (6.6%) classified as equivocal by Hadden and axonal by Rajabally. Due to more strictly defined cutoffs fewer patients fulfilled demyelinating criteria by Rajabally than by Hadden, making more patients eligible for axonal or equivocal classification by Rajabally. In 234 (68.6%) axonal studies by Rajabally the revised El Escorial (amyotrophic lateral sclerosis) criteria were fulfilled; in axonal cases by Hadden this was 1.8%. CONCLUSIONS AND DISCUSSION: This study shows that electrodiagnosis in GBS is dependent on the criterion set utilized, both of which are based on expert opinion. Reappraisal of electrodiagnostic subtyping in GBS is warranted.

Optic neuropathy after COVID-19 vaccination: a report of two cases.

PURPOSE: We report two cases of optic nerve pathology after the administration of the Pfizer-BioNTech and AstraZeneca-Oxford COVID-19 vaccines, respectively, and describe the implications for management of post-vaccination central nervous system (CNS) inflammation. CASE REPORTS: A 69-year-old woman presented with bilateral optic nerve head oedema, 16 days after the second dose of the Pfizer-BioNTech vaccine. She was diagnosed with post-vaccination CNS inflammatory syndrome and was treated for five days with intravenous methylprednisolone at a dose of 1 gram per day. Her optic disc swelling improved, and her vision stabilised. A 32-year-old woman presented six days after her first dose of the AstraZeneca-Oxford vaccine with two days of sudden onset of progressive blurring of vision in her left eye. Posterior segment examination revealed left optic disc swelling, and an MRI of the brain, orbit, and cervical spine was significant for left optic nerve enhancement. The patient was diagnosed with a unilateral post-vaccination optic neuritis. She was treated with a three-day course of intravenous methylprednisolone followed by oral prednisone. Her optic disc swelling and visual field improved, and she recovered 6/6 vision. CONCLUSIONS: Clinicians and patients should be aware of the potential for post-vaccination CNS inflammatory syndromes associated with COVID-19 vaccine administration. Neuroimaging and cerebrospinal fluid analysis may aid in the diagnosis of the cause of vision loss. Further studies are needed to evaluate the spectrum and frequency of optic nerve involvement associated with COVID-19 vaccination.

The spectrum of Epstein-Barr virus infections of the central nervous system after organ transplantation.

BACKGROUND: Epstein-Barr virus (EBV)-related neurologic complications have a diverse presentation in transplant recipients, creating diagnostic and therapeutic challenges for clinicians. In this case series, we report unique manifestations of EBV related neurologic complications following solid organ transplant and highlight pitfalls in management. CASE PRESENTATIONS: A retrospective search of the electronic medical record of all patients from January 2015 to December 2020 who underwent solid organ transplantation and had central nervous system complications as determined by ICD-10 codes were included. Three patients with unique manifestation of EBV-related neurologic complications after liver transplantation were identified. The first was a 52-year-old man with a live-donor liver transplant 11 years prior for Budd-Chiari syndrome presented with several weeks of headache and several lesions on brain MRI; he was diagnosed with primary central nervous system post-transplant lymphoproliferative disorder. The second patient was a 63-year-old man with a deceased-donor liver transplant 16 years prior for alpha-1-antitrypsin deficiency and was found to have a stroke; he was diagnosed with EBV encephalitis. The final patient was a 75-year-old woman with a deceased-donor liver transplant six years prior for primary biliary cirrhosis who presented with four months of gait instability; she was diagnosed with EBV myelitis. A review of the literature was performed to supplement description of the different diseases. CONCLUSIONS: EBV-related central nervous infection in post-transplant patients can manifest in a variety of neurologic syndromes, which can be challenging to diagnose. Careful correlation of clinical, pathologic, and radiologic findings and a high index of suspicion are crucial in identification and appropriate management.

Lyme disease presenting as multiple ischaemic strokes.

A 46-year-old man presented with recurrent left hemiparesis and headache. MRI of brain showed an acute right pontine and subacute right thalamic infarcts and MR angiogram showed multiple intracranial arterial stenoses, suggesting cerebral vasculopathy. There was a cerebrospinal fluid lymphocytic pleocytosis with Borrelia burgdorferi antibodies. Central nervous system Lyme disease occasionally presents with ischaemic strokes; this case is unusual in showing vasculopathy on brain imaging, supporting meningovasculitis as the likely mechanism.

Electrodiagnosis of Guillain-Barre syndrome in the International GBS Outcome Study: Differences in methods and reference values.

OBJECTIVE: To describe the heterogeneity of electrodiagnostic (EDx) studies in Guillain-Barré syndrome (GBS) patients collected as part of the International GBS Outcome Study (IGOS). METHODS: Prospectively collected clinical and EDx data were available in 957 IGOS patients from 115 centers. Only the first EDx study was included in the current analysis. RESULTS: Median timing of the EDx study was 7 days (interquartile range 4-11) from symptom onset. Methodology varied between centers, countries and regions. Reference values from the responding 103 centers were derived locally in 49%, from publications in 37% and from a combination of these in the remaining 15%. Amplitude measurement in the EDx studies (baseline-to-peak or peak-to-peak) differed from the way this was done in the reference values, in 22% of motor and 39% of sensory conduction. There was marked variability in both motor and sensory reference values, although only a few outliers accounted for this. CONCLUSIONS: Our study showed extensive variation in the clinical practice of EDx in GBS patients among IGOS centers across the regions. SIGNIFICANCE: Besides EDx variation in GBS patients participating in IGOS, this diversity is likely to be present in other neuromuscular disorders and centers. This underlines the need for standardization of EDx in future multinational GBS studies.

High-Resolution Ultrasound in the Diagnosis and Surgical Management of Ulnar Neuropathy at the Elbow.

High-resolution ultrasound (HRU) has recently demonstrated the potential to facilitate diagnosis and treatment of upper extremity compression neuropathy. The authors hypothesized that HRU can improve preoperative evaluation of ulnar neuropathy at the elbow (UNE) and that changes in ulnar nerve cross-sectional area (CSA) after cubital tunnel release may correlate with outcomes. Nineteen adult patients diagnosed with UNE who were scheduled for surgical decompression by a single hand surgeon were enrolled. Electrodiagnostic (EDX) testing, HRU of the ulnar nerve, Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) score, and McGowan grade were obtained pre- and postoperatively. Fourteen patients completed the study. Statistically significant improvements were found in CSA measurements and QuickDASH scores. High-resolution ultra-sound was found to confirm UNE in all 7 patients with positive results on EDX, and additionally detected UNE in 3 of 6 patients with negative results on EDX and in 1 patient with equivocal (nonlocalized) EDX testing. All 4 of these additional HRU-detected cases improved clinically and by CSA measurements after surgery. In this series, HRU was superior to EDX testing in the diagnosis of UNE and demonstrated objective improvement in ulnar nerve CSA after successful cubital tunnel release. This modality, which is better tolerated, less costly, and less time-consuming than EDX testing or magnetic resonance imaging, should therefore be considered in the diagnosis and surgical management of UNE, particularly in cases with negative or equivocal results on EDX testing, or when outcomes are suboptimal. [Orthopedics. 2021;44(5):285-288.].

Thalidomide neuropathy in childhood.

Thalidomide was withdrawn from world markets in 1961 following recognition of its teratogenic effects. More recently, however, thalidomide treatment has been reintroduced to adult and paediatric practice for a variety of dermatologic, immunologic, rheumatologic and neoplastic disorders. Neuropathy is a significant side effect of thalidomide therapy, which may limit its clinical use. We report four cases of sensorimotor axonal neuropathy in children aged 10-15 years, treated with thalidomide for myxopapillary ependymoma, Crohn's disease and recurrent giant aphthous ulceration. Thalidomide neuropathy is often associated with proximal weakness and may progress even after discontinuation of treatment, in the phenomenon of 'coasting'. Children treated with thalidomide should undergo regular neurophysiologic studies in order to detect presymptomatic or progressive peripheral neuropathy.

Frequent low penetrance mutations in the Lamin A/C gene, causing Emery Dreifuss muscular dystrophy.

Emery Dreifuss muscular dystrophy is a genetically heterogeneous disorder characterized by the clinical triad of early onset contractures, progressive muscular wasting and weakness with humeroperoneal distribution and cardiac conduction defects. Mutations in the Lamin A/C (LMNA) gene are responsible for the autosomal dominant and the autosomal recessive forms. Familiar and sporadic patients carrying mutations in the LMNA gene show high variability in the clinical symptomatology and age of onset. In this report, we describe four families harboring missense mutations in the LMNA gene and we show that the effect of mutations ranges from silent to fully penetrant. We suggest that incomplete penetrance of dominant mutations in the LMNA gene is a common feature and we emphasize the significance of mutational analysis in relatives of sporadic cases of laminopathies, as asymptomatic carriers face high risk of sudden cardiac death.

Cardiac features of Emery-Dreifuss muscular dystrophy caused by lamin A/C gene mutations.

AIMS: Retrospective studies have identified a mutation in the lamin A/C (LMNA) gene in patients selected on the basis of a phenotype characterized by dilated cardiomyopathy, atrioventricular conduction disturbances and sudden death. However, the features of cardiac abnormalities in patients with an initial diagnosis of Emery-Dreifuss muscular dystrophy (EDMD) are poorly known. Aim of the present study was to investigate the spectrum of cardiac disease in patients with an initial diagnosis of EDMD caused by a mutation in the LMNA gene. METHODS AND RESULTS: Ten consecutive patients with EDMD and a LMNA gene mutation were evaluated with structured medical interview, physical examination, ECG, echocardiogram and 24-h Holter monitoring. Electrophysiological testing and cardiac catheterization were performed if a class 1 or 2 American Heart Association guidelines indication was present. Cardiac disease was found in eight of 10 patients and consisted in the variable combination of supraventricular arrhythmias, disorders of atrioventricular conduction, ventricular arrhythmias, dilated cardiomyopathy, non-dilated cardiomyopathy, restrictive cardiomyopathy and sudden death despite pacemaker implant. CONCLUSIONS: Cardiac disease is common in patients with an initial diagnosis of EDMD caused by a mutation in the LMNA gene and consists of arrhythmias, disorders of atrioventricular conduction, cardiomyopathies and sudden death despite pacemaker implant.