Differentiating recurrent Guillain-Barre syndrome and acute-onset chronic inflammatory polyneuropathy: literature review.

Guillain-Barre syndrome (GBS) is an acute-onset immune-mediated polyneuropathy characterized by ascending symmetrical muscle weakness, diminished reflexes, and sensory symptoms. While GBS typically follows a monophasic course, some patients experience treatment-related fluctuations or recurrences, posing diagnostic challenges in distinguishing GBS from acute-onset chronic inflammatory polyneuropathy (A-CIDP). A-CIDP, may present acutely, simulating GBS, with a nadir in less than 8 weeks, subsequently evolving into a chronic or relapsing course. The distinction between recurrent GBS and A-CIDP is crucial, as A-CIDP necessitates long-term immunosuppression. A PubMed search was conducted using the search terms 'recurrent Guillain Barre syndrome' and 'acute onset CIDP' focusing on studies in the English language, published between January 1, 2004 and April 30, 2023. Overlapping clinical features, particularly in the early stages, complicate differentiation between recurrent GBS and CIDP. Electrophysiological studies, ultrasonography, and immunological markers have been explored for discrimination; however, definitive criteria for differentiation remain elusive. Recent follow-up studies have further blurred the boundaries between recurrent GBS and A-CIDP, suggesting the persistence of underlying immune processes even in GBS patients without clinical deterioration. This emphasizes the necessity of reevaluating diagnostic criteria and treatment strategies. In conclusion, distinguishing recurrent GBS from A-CIDP remains an ongoing challenge. Existing evidence questions the categorization of recurrent GBS as a distinct entity, challenging its very existence. Continued research is necessary to refine diagnostic criteria and deepen our understanding of these conditions, ultimately advancing patient care. This review delves into the intricacies of recurrent GBS and A-CIDP differentiation and highlights the need for a reevaluation of the recurrent GBS concept.

IgG4-related pachymeningitis-Long term follow up and outcome of six patients.

OBJECTIVE: Our understanding of IgG4-RD and pachymeningitis has grown substantially, but the optimal approach for diagnosis, management, and long-term outcomes is still an area of uncertainty. METHODS: HUVAC is a database for IgG4-RD patients, this database was retrospectively evaluated for pachymeningeal disease. Demographic, clinical, serological, imaging, histopathological data, and treatment details were re-interpreted in patients with pachymeningitis. RESULTS: Among 97 patients with IgG4-RD, 6 (6.2%) had pachymeningitis. None of these patients had extracranial features, and also, in most of the patients, serum IgG4 levels were normal. Tentorium cerebelli and transverse sinus dura were the most commonly involved in the posterior fossa. During 18 months of median follow-up on steroid+-rituximab, none of them relapsed as pachymeningitis. CONCLUSION: Our patients were mainly older males with sole neurological involvement. Non-specific headache was the most common manifestation, and serum IgG4 levels were not useful for diagnosis. Typical radiology and tentorial thickening should suggest IgG4-RD and prompt an early biopsy. Moreover, accompanying hypophysitis could also be a clue. With steroids+ rituximab treatment, no relapse related to meningeal involvement was seen in long-term follow-up.

Patient with recurrent neuralgic amyotrophy; right brachial plexitis and left posterior interosseous neuropathy.

Neuralgic amyotrophy (NA), also known as Parsonage-Turner syndrome or idiopathic brachial plexopathy, is a multifocal inflammatory neuropathy that usually affects the upper limbs. The classic picture is a patient with acute onset of asymmetric upper extremity symptoms, excruciating pain, rapid onset of multifocal paresis often involving winged scapula, and a monophasic course of the disease. 
We present an unusual case of recurrent NA characterized first by right brachial plexitis and then isolated left posterior interosseous nerve palsy. 

The evaluation of small fibers in multiple sclerosis.

BACKGROUND: Dysesthetic or ongoing extremity pain is a common symptom in all multiple sclerosis (MS) types. Although the pathology of the disease is the demyelination of central neurons, the patients may also complain of neuropathic pain in distal extremities that is generally related to A-delta and C fiber dysfunction. It is not known whether thinly myelinated and unmyelinated fibers are affected in MS patients. We aim to investigate the small fiber loss and its length dependency. METHODS: We evaluated the skin biopsy taken from proximal and distal leg of MS patients with neuropathic pain. Six patients with primary progressive MS (PPMS), seven with relapsing-remitting MS (RRMS), seven with secondary progressive MS (SPMS) and as a control group ten age and sex-matched healthy controls were included. Neurological examination, electrophysiological evaluation and DN4 questionnaire were performed. Subsequently, skin punch biopsy from 10 cm above the lateral malleolus and proximal thigh were done. The biopsy samples were stained with PGP9.5 antibody and intraepidermal nerve fiber density (IENFD) was determined. RESULTS: The mean proximal IENFD was 8.58±3.58 fibers/mm among MS patients and 14.72±2.89 fiber/mm among healthy controls (p=0.001). However, the mean distal IENFD did not differ between MS patients and healthy controls (9.26±3.24 and 9.75±1.6 fiber/mm respectively. Although proximal and distal IENFD tends to be lower in MS patients with neuropathic pain, there was no statistically significant difference between MS patients with and without neuropathic pain CONCLUSION: Although MS is a demyelinating disease, unmyelinated fibers can also be affected. Our findings suggest non-length dependent small fiber neuropathy in MS patients.

Nusinersen for adults with spinal muscular atrophy.

INTRODUCTION: Nusinersen was effective in improving motor function and survival in infantile and childhood-onset spinal muscular atrophy (SMA), and the value of real-world experiences in adult SMA patients increase gradually. Here, we present our clinical experience in adult SMA patients treated with nusinersen according to CHERISH study. MATERIAL AND METHODS: Thirty-two SMA patients treated with nusinersen were included in the study. RESULTS: Median age at nusinersen initiation was 33.5 (20.0-60.0) years and 23 of SMA patients were male. Six (18.8%) patients had SMA type 2, and 26 (81.2%) had SMA type 3. Median follow-up period of patients under nusinersen treatment was 17 months (9-21). Twenty-three patients improved by at least 3 Hammersmith Functional Motor Scale Expanded (HFMSE) points after loading doses. There was significant HFMSE score increase in type 3 patients at each time point, whereas type 2 patients seem to benefit from nusinersen loading doses, subsequently stayed stable. Motor improvement was positively correlated with baseline HFMSE scores in patients whose baseline HFMSE scores were ≤47. There was a correlation between the changes in Amyotrophic Lateral Sclerosis Functional Rating Scale Revised (ALSFRS-R) score and HFMSE scores. Ambulatory patients who could not show clinically meaningful increase in HFMSE scores improved at least 30 m by 6-min walk test (6MWT). CONCLUSION: Overall, 78% of patients have responded to treatment according to HFMSE or 6MWT. ALSFRS-R and 6MWT may be alternative tools to monitor nusinersen effect.

Immunotherapy Provides Electrophysiological Recovery and Excellent Clinical Response in Sjogren's Syndrome-Linked Quite Severe Autonomic Neuropathy.

INTRODUCTION: The autonomic system is frequently affected in Sjogren's syndrome (SS), but presentation with severe autonomic neuropathy is infrequent. Herein, we present a patient with primary SS-linked autonomic neuropathy, which is significantly clinic and electrophysiological responsive to immunotherapy. CASE REPORT: A 29-year-old female patient was admitted to our neurology department with recurrent syncope, postural light-headedness, and weight loss. Neurological examination revealed tonic pupils. The baseline composite autonomic symptom score-31 was 51 (0 to 75), and baseline functional ability score was 10 (0 to 100%). In the follow-up, syncope episodes that frequently develop during the day required the patient to lie in the supine position in bed all day and were triggered even by coming to a slightly sitting position. Neurophysiologic testing showed evidence of cardiovagal and sudomotor impairment. The patient was diagnosed with SS after detailed investigations. A 5-day course of intravenous immunoglobulin (IVIg) was given, and she continued IVIg once a month. After 6 months, she could walk long distances without support, and gastrointestinal complaints and syncopes had significantly decreased. After ~1.5 years, she had a composite autonomic symptom score-31 score of 11 and a functional ability score of 80%. Control heart rate variability analysis showed a significant improvement in the values of SD of the RR interval and root mean square of successive RR interval differences. CONCLUSIONS: In SS-linked severe autonomic neuropathy, immunotherapy can provide electrophysiological recovery in addition to excellent clinical response.

Multimodal assessment of intensive care unit-acquired weakness in severe stroke patients.

BACKGROUND: Intensive care unit-acquired weakness (ICUAW) defines generalized muscle weakness seen in critically ill patients in the absence of other causative factors. Herein, we aimed to evaluate ICUAW in stroke patients by electrodiagnostic testing, histopathology, and assessment of respiratory complex activities (RCA), to define the frequency of ICUAW in this patient group, and to reach new parameters for early prediction and diagnosis. METHODS: We prospectively recruited twenty-four severe acute stroke patients during a sixteen-month period. In addition to serial nerve conduction studies (NCS), we performed muscle biopsy and RCA analysis on the non-paretic side when ICUAW developed. Patients undergoing orthopedic surgery without metabolic and neuromuscular diseases constituted the control group for RCA. Survival and longitudinal data were analyzed by joint modeling to determine the relationship between electrophysiological parameters and ICUAW diagnosis. RESULTS: Eight patients (33%) developed ICUAW, and six of them within the first two weeks. Extensor digitorum brevis, abductor digiti minimi (ADM), rectus femoris and vastus medialis (VM) compound muscle action potential (CMAP) amplitudes showed a significant decrease in the ICUAW group. VM CMAP amplitude (BIC = 358.1574) and ADM CMAP duration (BIC = 361.1028) were the best-correlated parameters with ICUAW diagnosis. The most informative electrophysiological findings during the entire study were obtained within the first 11 days. Muscle biopsies revealed varying degrees of type 2 fiber atrophy. Complex I (p = 0.003) and IV (p = 0.018) activities decreased in patients with ICUAW compared to controls. CONCLUSION: VM CMAP amplitude and ADM CMAP duration correlate well with ICUAW diagnosis, and may aid in the early diagnosis.

Bilateral Wrist Drop Caused by Non-invasive Continuous Monitoring of Blood Pressure During Severe COVID-19 Pneumonia: A Case Report.

Compressive peripheral nerve injury can be observed as a long-term outcome during the treatment of severe COVID-19 pneumonia. In this case study, we report a man with bilateral wrist drop due to prolonged noninvasive blood pressure monitoring. A 52-year-old man who had undergone invasive ventilation because of severe COVID-19 pneumonia was admitted with bilateral loss of function of the wrist, digital, and thumb extensors and hypoesthesia in the dorsum of the forearm and hand. The patient had not been treated with prone positioning respiratory therapy. However, he had undergone bilateral automated sphygmomanometry that measured his blood pressure every ten minutes during his ICU stay. His electrophysiological findings were compatible with the presence of bilateral radial nerve compression at the level of the spiral groove. Awareness of potential compressive peripheral nerve injury is important for rehabilitation after the treatment of COVID-19-associated pneumonia.

The functional and structural evaluation of small fibers in asymptomatic carriers of TTR p.Val50Met (Val30Met) mutation.

Therapeutic advances in hereditary amyloid transthyretin (ATTRv) amyloidosis with polyneuropathy extended life expectancy and delayed symptom progression especially in patients with early disease. Thus, detection and monitoring of asymptomatic carriers gained importance. However, there is still limited consensus on genetic screening of ATTRv-polyneuropathy patients' family members and diagnostic tests that must be done in the follow-up. In this study, we followed prospectively five asymptomatic carriers of a family with ATTRV30M (p.Val50Met) mutation by different diagnostic tests for three years. The carriers were followed by neurological examination, nerve conduction studies, sympathetic skin response test, heart rate variability, SFN-SIQ and DN4 questionnaires, quantitative sensory testing (QST), skin biopsy and in vivo corneal confocal microscopy. Nerve conduction studies, sympathetic skin response test and heart rate variability were normal in all for three years. Baseline QST and SFN-SIQ were normal but became abnormal during follow-up of two individuals who developed small fiber neuropathy symptoms. Baseline intraepidermal nerve fiber density was low in three carriers and decreased to below normative values in all during follow-up, while corneal sub-basal nerve density was low in all carriers compared to controls during the entire follow-up. Thus, our study showed that SFN-SIQ and QST are useful diagnostic tools to detect the transition to symptomatic ATTRv-polyneuropathy.

A combined clinical and computational approach to understand the SOD1A4T-mediated pathogenesis of rapidly progressive familial amyotrophic lateral sclerosis.

Here, we aim to provide a comprehensive clinical and biomolecular description of familial amyotrophic lateral sclerosis (fALS) in a 25-year-old female patient with respect to the SOD1A4T genotype. The clinical diagnosis of the disease was based on family history, neurological examination, electroneurophysiological studies, and revised El Escorial criteria. The heterozygous presence of the A4T mutation in the proband was confirmed by PCR coupled with Sanger sequencing of exon 1 of the SOD1 gene. The mutation was introduced in silico into the three-dimensional structure of the native protein. After energy minimization and quality assessment, non-covalent interactions around threonine-4 and changes in protein stability were calculated computationally. The patient differed widely in age at onset, initial neurological symptoms and findings, and survival time from her kindred, in which several members are affected. SOD1A4T-linked fALS in this case had bulbar involvement at onset, a combination of lower and upper motor neuron signs and showed rapid progression. Unlike alanine-4, threonine-4 failed to engage in hydrophobic interactions with the vicinal non-polar amino acids. The overall fold of the modeled SOD1A4T mutant remained intact, but unfolding free energy estimations disclosed a decrease in the protein's stability. We report a phenotypically distinct patient with fALS due to the SOD1A4T mutation and further expand the largest pedigree ever published for SOD1A4T-linked fALS. Genotype‒phenotype correlation in fALS is complex, and it demands detailed clinical investigation and advanced scientific research. Awareness of the broadened phenotypic spectrum might potentially enhance the diagnosis and genetic counseling of fALS.

Two distinct skeletal muscle microRNA signatures revealing the complex mechanism of sporadic ALS.

Skeletal muscle pathology is thought to have an important role in the onset and/or progression of amyotrophic lateral sclerosis (ALS), which is a neurodegenerative disorder characterized by progressive muscle weakness. Since miRNAs are recognized as important regulatory factors of essential biological processes, we aimed to identify differentially expressed miRNAs in the skeletal muscle of sporadic ALS patients through the combination of molecular-omic technologies and bioinformatic tools. We analyzed the miRnome profiles of skeletal muscle biopsies acquired from ten sALS patients and five controls with Affymetrix GeneChip miRNA 4.0 Array. To find out differentially expressed miRNAs in patients, data were analyzed by The Institute for Genomic Research-Multi Experiment Viewer (MeV) and miRNAs whose expression difference were statistically significant were identified as candidates. The potential target genes of these miRNAs were predicted by miRWalk 2.0 and were functionally enriched by gene ontology (GO) analysis. The expression level of priority candidates was validated by quantitative real-time PCR (qRT-PCR) analysis. We identified ten differentially expressed miRNAs in patients with a fold change threshold ≥ 2.0, FDR = 0. We identified ten differentially expressed miRNAs in patients with a fold change threshold ≥ 2.0, FDR = 0. Nine out of the ten miRNAs were found to be related to top three enriched ALS-related terms. Based on the qRT-PCR validation of candidate miRNAs, patients were separated into two groups: those with upregulated miR-4429 and miR-1825 expression and those with downregulated miR-638 expression. The different muscle-specific miRNA profiles in sALS patients may indicate the involvement of etiologic heterogeneity, which may allow the development of novel therapeutic strategies.

Neuropathic Pain Frequency in Neurology Outpatients: A Multicenter Study.

INTRODUCTION: Neuropathic pain is common, but the frequency of misdiagnosis and irrational treatment is high. The aim of this study is to evaluate the rate of neuropathic pain in neurology outpatient clinics by using valid and reliable scales and review the treatments of patients. METHODS: The study was conducted for 3 months in eleven tertiary health care facilities. All outpatients were asked about neuropathic pain symptoms. Patients with previous neuropathic pain diagnosis or who have neuropathic pain symptoms were included and asked to fill painDETECT and douleur neuropathic en 4 questions (DN4) questionnaire. Patients whose DN4 score is higher than 3 and/or painDETECT score higher than 13 and/or who are on drugs for neuropathic pain were considered patients with neuropathic pain. The frequency of neuropathic pain was calculated and the treatments of patients with neuropathic pain were recorded. RESULTS: Neuropathic pain frequency was 2.7% (95% CI: 1.5-4.9). The most common cause was diabetic neuropathy. According to painDETECT, the mean overall pain intensity was 5.7±2.4, being lower among patients receiving treatment. Pharmacological neuropathic pain treatment was used by 72.8% of patients and the most common drug was pregabalin. However, 70% of those receiving gabapentinoids were using ineffective doses. Besides, 4.6% of the patients were on medications which are not listed in neuropathic pain treatment guidelines. CONCLUSION: In our cohort, the neuropathic pain severity was moderate and the frequency was lower than the literature. Although there are many guidelines, high proportion of patients were being treated by ineffective dosages or irrational treatments.

A case with Neurofascin-155 IgG antibody-associated combined central and peripheral demyelination: Successfully treated with anti-CD20 monoclonal antibody.

Combined central and peripheral demyelination (CCPD) is an infrequent entity in which demyelination is observed in central (CNS) and peripheral nervous systems (PNS). Potentially, it may develop due to a shared immune mechanism or possible co-occurrence between two unrelated demyelinating diseases such as multiple sclerosis (MS) and chronic inflammatory demyelination polyneuropathy (CIDP). A small number of CIDP patients have autoantibodies against nodal and paranodal proteins such as neurofascin155 (NF155). NF acts as a cell adhesion molecule between nodal and paranodal proteins. Glial NF 155 coexists in the PNS and CNS and can lead to combined demyelination. Although NF antibody-positive CIDP cases and case series have been reported, the number of patients with overt manifestations of central nervous system demyelination is very low in this group. The response to intravenous immunoglobulin (IVIg) in anti NF155 antibody-positive (NF155 +) CIDP is known to be poor. Rituximab, a B-cell-targeted anti-CD20 monoclonal antibody, has made good progress in therapy. Here, we report a case with Neurofascin-155 IgG antibodies related to CCPD who responded well to Rituximab. NF155+ CIDP usually affects young adults, and early administration of appropriately combined immunotherapy can prevent severe disability. NF antibody testing should be performed in unresponsive patients to IVIg therapy.

Cognitive impairment and affective disorder: A rare presentation of cerebellar stroke.

The awareness of the "Cerebellar Cognitive Affective Syndrome" (CCAS) as a clinical entity is emerging. The CCAS is characterized by impaired executive functions, linguistic skills, visuospatial cognition and personality change. Here we report a 56-year-old, male teacher who developed acute psychomotor retardation, low energy level, infrequent speech, and mild cognitive decline. Two months before admission, he was initially diagnosed as depression, and later misdiagnosed as encephalitis, which misled him to receive high-dose intravenous steroids and antimicrobial drugs. The Brain MRI revealed multiple posterior cerebellar infarcts predominantly at the lobules VII and VIII. The standard neuropsychological tests were unremarkable; however, the CCAS Scale confirmed the diagnosis. The treatment of depression and secondary prevention of stroke was conducted. In cases that present with features of cognitive and affective disorders but with mild voluntary motor or without typical cerebellar features, the role of posterior cerebellar and vermian pathologies should be considered. The CCAS Scale is an appropriate screening tool to detect these patients and provides a framework for evidence-based treatment.

Comprehensive clinical, biochemical, radiological and genetic analysis of 28 Turkish cases with suspected metachromatic leukodystrophy and their relatives.

Metachromatic leukodystrophy (MLD) is a glycosphingolipid storage disease caused by deficiency of the lysosomal enzyme arylsulfatase A (ASA) or its activator protein saposin B. MLD can affect all age groups in severity varying from a severe fatal form to milder adult onset forms. Diagnosis is usually made by measuring leukocyte ASA activity. However, this test can give false negative or false positive laboratory results due to pseudodeficiency of ASA and saposin B deficiency, respectively. Therefore, we aimed to evaluate patients with suspected MLD in a Turkish population by comprehensive clinical, biochemical, radiological, and genetic analyses for molecular and phenotypic characterization. We analyzed 28 suspected MLD patients and 41 relatives from 24 families. ASA activity was found to be decreased in 21 of 28 patients. Sixteen patients were diagnosed as MLD (11 late infantile, 2 juvenile and 3 adult types), 2 MSD, 2 pseudodeficiency (PD) and the remaining 8 patients were diagnosed as having other leukodystrophies. Enzyme analysis showed that the age of onset of MLD did not correlate with residual ASA activity. Sequence analysis showed 11 mutations in ARSA, of which 4 were novel (p.Trp195GlyfsTer5, p.Gly298Asp, p.Arg301Leu, and p.Gly311Asp), and 2 mutations in SUMF1 causing multiple sulfatase deficiency, and confirmed the diagnosis of MLD in 2 presymptomatic relatives. All individuals with confirmed mutations had low ASA activity and urinary sulfatide excretion. Intra- and inter-familial variability was high for the same ARSA missense genotypes, indicating the contribution of other factors to disease expression. Imaging findings were evaluated through a modified brain MRI scoring system which indicated patients with protein-truncating mutations had more severe MRI findings and late-infantile disease onset. MRI findings were not specific for the diagnosis. Anti-sulfatide IgM was similar to control subjects, and IgG, elevated in multiple sulfatase deficiency. In conclusion, the knowledge on the biochemical, clinical and genetic basis of MLD was expanded, a modified diagnostic laboratory algorithm for MLD based on integrated evaluation of ASA activity, urinary sulfatide excretion and genetic tests was devised.

Revisiting the complex architecture of ALS in Turkey: Expanding genotypes, shared phenotypes, molecular networks, and a public variant database.

The last decade has proven that amyotrophic lateral sclerosis (ALS) is clinically and genetically heterogeneous, and that the genetic component in sporadic cases might be stronger than expected. This study investigates 1,200 patients to revisit ALS in the ethnically heterogeneous yet inbred Turkish population. Familial ALS (fALS) accounts for 20% of our cases. The rates of consanguinity are 30% in fALS and 23% in sporadic ALS (sALS). Major ALS genes explained the disease cause in only 35% of fALS, as compared with ~70% in Europe and North America. Whole exome sequencing resulted in a discovery rate of 42% (53/127). Whole genome analyses in 623 sALS cases and 142 population controls, sequenced within Project MinE, revealed well-established fALS gene variants, solidifying the concept of incomplete penetrance in ALS. Genome-wide association studies (GWAS) with whole genome sequencing data did not indicate a new risk locus. Coupling GWAS with a coexpression network of disease-associated candidates, points to a significant enrichment for cell cycle- and division-related genes. Within this network, literature text-mining highlights DECR1, ATL1, HDAC2, GEMIN4, and HNRNPA3 as important genes. Finally, information on ALS-related gene variants in the Turkish cohort sequenced within Project MinE was compiled in the GeNDAL variant browser (www.gendal.org).

The Sole Initial Imaging Finding in Creutzfeldt-Jacob Disease: Focal FDG-PET Hypometabolism.

Laboratory studies such as electroencephalography, cerebrospinal fluid examination and diffusion-weighted magnetic resonance imaging (DWI-MRI) are valuable in the diagnosis of Creutzfeldt-Jacob disease (CJD),. However, these laboratory studies may not show the characteristic findings in the very early stage of the disease. Here, we present a case of CJD who had atypical neurologic presentation initially and had only a focal parietal 2-(18F) fluorodeoxyglucose (FDG) positron emission tomography (PET) hypometabolism as the sole imaging abnormality at the beginning. The patient progressed rapidly, and showed typical neurological findings for CJD. The brain MRI was performed two weeks after the FDG-PET study, finally demonstrated increased signal intensity in DWI in caudat nucleus, putamen, and cerebral cortex, especially on left parietal region. Imaging methods demonstrating functional alterations in the brain should be obtained in the early period in patients with normal MRI suspected having CJD. Repeating DWI could also be an effective diagnostic approach.