Inclusion of optic neuritis in dissemination in space improves the performance of McDonald 2017 criteria in Hispanic people with suspected multiple sclerosis.

BACKGROUND: Hispanic people compared to White people with multiple sclerosis (MS) are two times more likely to present with optic neuritis (ON). ON in dissemination in space (DIS) after a single attack is not part of the current McDonald 2017 criteria. OBJECTIVE: To evaluate if adding ON in DIS (ON-modified criteria) improves the performance of the McDonald 2017 criteria in the diagnosis of MS after a single attack of ON. METHODS: Retrospective study of 102 patients of Hispanic background. Cases were reviewed between 2017 and 2021. Clinical ON was reported for 35 cases. ON in DIS was verified for 28 patients via MRI, optical coherence tomography, and/or visual evoked potential. We investigated the performance of the McDonald 2017 criteria and ON-modified criteria and calculated sensitivity, specificity, positive and negative predictive values, and accuracy. RESULTS: The ON-modified criteria significantly improved the performance of the McDonald 2017 criteria (p = 0.003) and identified an additional nine patients. Both sensitivity and accuracy increased from 64% to 74% and 62% to 71%, respectively, while specificity remained unchanged (40% (95% confidence interval (CI): 0.10, 0.70)). CONCLUSION: This study provides evidence that the inclusion of ON in DIS improved the overall performance of the McDonald 2017 criteria among Hispanic people.

Real-world challenges in the diagnosis of primary progressive multiple sclerosis.

BACKGROUND AND PURPOSE: Despite the 2017 revisions to the McDonald criteria, diagnosing primary progressive multiple sclerosis (PPMS) remains challenging. To improve clinical practice, the aim was to identify frequent diagnostic challenges in a real-world setting and associate these with the performance of the 2010 and 2017 PPMS diagnostic McDonald criteria. METHODS: Clinical, radiological and laboratory characteristics at the time of diagnosis were retrospectively recorded from designated PPMS patient files. Possible complicating factors were recorded such as confounding comorbidity, signs indicative of alternative diagnoses, possible earlier relapses and/or incomplete diagnostic work-up (no cerebrospinal fluid examination and/or magnetic resonance imaging brain and spinal cord). The percentages of patients fulfilling the 2010 and 2017 McDonald criteria were calculated after censoring patients with these complicating factors. RESULTS: A total of 322 designated PPMS patients were included. Of all participants, it was found that n = 28/322 had confounding comorbidity and/or signs indicative of alternative diagnoses, n = 103/294 had possible initial relapsing and/or uncertainly progressive phenotypes and n = 73/191 received an incomplete diagnostic work-up. When applying the 2010 and 2017 diagnostic PPMS McDonald criteria on n = 118 cases with a full diagnostic work-up and a primary progressive disease course without a better alternative explanation, these were met by 104/118 (88.1%) and 98/118 remaining patients (83.1%), respectively (p = 0.15). CONCLUSION: Accurate interpretation of the initial clinical course, consideration of alternative diagnoses and a full diagnostic work-up are the cornerstones of a PPMS diagnosis. When these conditions are met, the 2010 and 2017 McDonald criteria for PPMS perform similarly, emphasizing the importance of their appropriate application in clinical practice.

The kappa free light chain index and oligoclonal bands have a similar role in the McDonald criteria.

Intrathecal production of kappa free light chains occurs in multiple sclerosis and can be measured using the kappa free light chain index. Kappa free light chain index values can be determined more easily than oligoclonal bands detection and seem more sensitive than the immunoglobulin (Ig)G index to diagnose multiple sclerosis. We assessed the value of oligoclonal bands, kappa free light chain index cut-offs 5.9, 6.6 and 10.61, and IgG index to diagnose multiple sclerosis with prospectively acquired data from a clinically isolated syndrome inception cohort. We selected patients with sufficient data to determine oligoclonal bands positivity, MRI dissemination in space and time, IgG index and sufficient quantities of paired CSF and blood samples to determine kappa free light chain indexes (n = 214). We used Kendall's Tau coefficient to estimate concordance, calculated the number of additional diagnoses when adding each positive index to dissemination in space and positive oligoclonal bands, performed survival analyses for oligoclonal bands and each index with the outcomes second attack and 2017 MRI dissemination in space and time and estimated the diagnostic properties of oligoclonal bands and the different indexes for the previously mentioned outcomes at 5 years. Oligoclonal bands were positive in 138 patients (64.5%), kappa free light chain-5.9 in 136 (63.6%), kappa free light chain-6.6 in 135 (63.1%), kappa free light chain-10.61 in 126 (58.9%) and IgG index in 101 (47.2%). The highest concordance was between oligoclonal bands and kappa free light chain-6.6 (τ = 0.727) followed by oligoclonal bands and kappa free light chain-5.9 (τ = 0.716). Combining dissemination in space plus oligoclonal bands or kappa free light chain-5.9 increased the number of diagnosed patients by 11 (5.1%), with kappa free light chain-6.6 by 10 (4.7%), with kappa free light chain-10.61 by 9 (4.2%) and with IgG index by 3 (1.4%). Patients with positive oligoclonal bands or indexes reached second attack and MRI dissemination in space and time faster than patients with negative results (P < 0.0001 except IgG index in second attack: P = 0.016). In multivariable Cox models [adjusted hazard ratio (95% confidence interval)], the risk for second attack was very similar between kappa free light chain-5.9 [2.0 (0.9-4.3), P = 0.068] and kappa free light chain-6.6 [2.1 (1.1-4.2), P = 0.035]. The highest risk for MRI dissemination in space and time was demonstrated with kappa free light chain-5.9 [4.9 (2.5-9.6), P < 0.0001], followed by kappa free light chain-6.6 [3.4 (1.9-6.3), P < 0.0001]. Kappa free light chains-5.9 and -6.6 had a slightly higher diagnostic accuracy than oligoclonal bands for second attack (70.5, 71.1 and 67.8) and MRI dissemination in space and time (85.7, 85.1 and 81.0). Kappa free light chain indexes 5.9 and 6.6 performed slightly better than oligoclonal bands to assess multiple sclerosis risk and in terms of diagnostic accuracy. Given the concordance between oligoclonal bands and these indexes, we suggest using dissemination in space plus positive oligoclonal bands or positive kappa free light chain index as a modified criterion to diagnose multiple sclerosis.

Identification of demyelinating lesions and application of McDonald criteria when confronted with white matter lesions on brain MRI.

INTRODUCTION: White matter lesions (WML) on magnetic resonance imaging (MRI) are common in clinical practice. When analyzing WML, radiologists sometimes propose a pathophysiological mechanism to explain the observed MRI abnormalities, which can be a source of anxiety for patients. In some cases, discordance may appear between the patient's clinical symptoms and the identification of the MRI-appearing WML, leading to extensive diagnostic work-up. To avoid misdiagnosis, the analysis of WML should be standardized, and a consensual MRI reading approach is needed. OBJECTIVE: To analyze the MRI WML identification process, associated diagnosis approach, and misinterpretations in physicians involved in WML routine practice. METHODS: Through a survey distributed online to practitioners involved in WML diagnostic work-up, we described the leading causes of MRI expertise misdiagnosis and associated factors: clinical experience, physicians' subspecialty and location of practice, and type of device used to complete the survey. The survey consisted of sixteen T2-weighted images MRI analysis, from which ten were guided (binary response to lesion location identification), four were not shown (multiple possible answers), and two were associated with dissemination in space (DIS) McDonald criteria application. Two independent, experienced practitioners determined the correct answers before the participants' completion. RESULTS: In total, 364 participants from the French Neuro Radiological (SFNR), French Neurological (SFN), and French Multiple Sclerosis (SFSEP) societies completed the survey entirely. According to lesion identification, 34.3% and 16.9% of the participants correctly identified juxtacortical and periventricular lesions, respectively, whereas 56.3% correctly identified non-guided lesions. Application of the 2017 McDonald's DIS criteria was correct for 35.3% of the participants. According to the global survey scoring, factors independently associated with correct answers in multivariate analysis were MS-expert subspecialty (P<0.001), young clinical practitioners (P=0.02), and the use of a computer instead of a smartphone to perform WML analysis (P=0.03). CONCLUSION: Our results highlight the difficulties regarding WML analysis in clinical practice and suggest that radiologists and neurologists should rely on each other to ensure the diagnosis of multiple sclerosis and related disorders and limit misdiagnoses.

[Diagnostic imaging in multiple sclerosis]. / Bildgebende Diagnostik bei multipler Sklerose.

Multiple sclerosis (MS) is an inflammatory autoimmune disease that leads to the development of demyelination foci in the central nervous system and can affect any neurological function. In the developed world, it represents the most common chronic neurological (nontraumatic) disease in young and middle-aged patients. Magnetic resonance imaging (MRI) is the first-line imaging modality for the diagnosis and follow-up of MS. The currently valid McDonald criteria, updated in 2017, define the exact morphological imaging criteria for diagnosing MS. In addition to the detection of typical MS plaques, the determination of spatial and temporal dissemination is essential for the initial diagnosis. A standardized MRI protocol consisting of mandatory and optional sequences is recommended for reliable diagnosis and differentiation from a broad spectrum of differential diagnoses.

Challenges in multiple sclerosis diagnosis: Misunderstanding and misapplication of the McDonald criteria.

OBJECTIVE: To assess comprehension and application of the McDonald criteria. BACKGROUND: Studies suggest that knowledge gaps for specific core elements of the McDonald criteria may contribute to multiple sclerosis (MS) misdiagnosis. METHODS: Neurology residents (NR) and multiple sclerosis specialists (MSS) in North America completed a web-based survey. RESULTS: A total of 160 participants were included: 72 NR and 88 MSS. Syndromes incorrectly identified as typical of MS included: complete transverse myelopathy (35% NR and 15% MSS), intractable vomiting/nausea/hiccoughs (20% NR and 5% MSS), and bilateral optic neuritis/unilateral optic neuritis with poor visual recovery (17% NR and 10% MSS). Periventricular magnetic resonance imaging (MRI) lesions were correctly identified by 39% NR and 52% MSS, and juxtacortical lesions were correctly identified by 28% NR and 53% MSS. The correct definition of "periventricular" was chosen by 38% NR and 61% MSS, and that of "juxtacortical" was chosen by 19% NR and 54% MSS. Regions incorrectly identified for MRI dissemination in space fulfillment included the optic nerve (31% NR and 26% MSS) and the subcortical white matter (11% NR and 18% MSS). The majority of participants assessed previous non-specific neurological symptoms without objective evidence of a central nervous system (CNS) lesion as sufficient for clinical dissemination in time. CONCLUSION: The McDonald criteria are often misunderstood and misapplied. Concerted educational efforts may prevent MS misdiagnosis.

Primary progressive multiple sclerosis presenting under the age of 18 years: Fact or fiction?

Previous cohort studies on paediatric multiple sclerosis (MS) have reported very low frequencies for a primary progressive MS (PPMS) course ranging from 0% to 7%. We identified six patients presenting prior to the age of 18 years and fulfilling the 2017 McDonald Criteria for PPMS. Presentation with progressive neurological symptoms and signs in young people should prompt evaluation for genetic causes such as leukodystrophies, hereditary spastic paraparesis and mitochondrial diseases given the rarity of primary progressive course in paediatric MS. In the absence of an alternative diagnosis, with new therapeutic options becoming available for PPMS, this diagnosis should then be considered.

Demographic and clinical profile of patients with multiple sclerosis diagnosed over the last 30 years according to different diagnostic criteria.

The aim of this study was to investigate the demographic and clinical characteristics of patients with multiple sclerosis (MS) diagnosed between 1986 and 2015. 333 patients with definite MS were divided into four subgroups according to the following diagnostic criteria: Group A) Poser (n = 145), Group B) McDonald 2000 (n = 66), Group C) McDonald 2005 (n = 62), and Group D) McDonald 2010 (n = 60). We investigated: 1) patient sex and age at diagnosis, 2) symptoms and number of relapses that prompted MS diagnosis, 3) time between first symptoms suggestive of MS and confirmed diagnosis, and 5) Expanded Disability Status Scale (EDSS) score at disease onset. The overall female-to-male ratio was 2.3:1, but in the subgroups it differed significantly (A - 1.9; B - 1.6; C - 4.7; D - 3.6). The mean age at diagnosis (in years) decreased from 39.6 ± 13.3 in Group A to 29.9 ± 9.3 in Group D, p < 0.001. Pyramidal signs remained the most common manifestation regardless of the diagnostic criteria, although an increased trend of visual dysfunction was observed (A - 16%, B - 14%, C - 19%, D - 23,3%; A vs D, p < 0.001). The number of relapses before diagnosis decreased from median 4.0 to 2.5 in Group A and Group D, p < 0.001. Time from the first symptom to diagnosis shortened from 88.9 ± 80.2 months (Group A) to 33.6 ± 68.2 months (Group D), p < 0.0001. Mean EDSS score at diagnosis also decreased: A - 4.4 ± 2.3; B - 3.1 ± 1.7; C - 2.7 ± 1.3; D - 2.8 ± 1.4, p < 0.001. Our study indicates significant differences in demographic and clinical characteristics of MS diagnosed according to the changing criteria.

Pure spinal multiple sclerosis: A possible novel entity within the multiple sclerosis disease spectrum.

We identified five female patients retrospectively with relapsing short-segment partial myelitis whose clinical and paraclinical features were suggestive of cord involvement of multiple sclerosis (MS)-type albeit not rigidly fulfilling the 2017 McDonald criteria. Notably, these patients had not developed any typical MS-like brain lesions despite repeated neuroimaging assessments over years. Comprehensive work-up for differential diagnoses of MS and other causes of transverse myelitis particularly neuromyelitis optica spectrum disorders had been consistently negative on longitudinal follow-up. Thus, we postulate a possible entity of pure spinal MS which may represent a novel forme fruste within the MS disease spectrum.

Pediatric Multiple Sclerosis: an Update.

PURPOSE OF REVIEW: Diagnostic criteria for pediatric-onset multiple sclerosis (POMS) and related demyelinating disorders have been updated, neuroimaging studies have revealed new insights, biological assays identify patients with specific antibodies that influence both diagnosis and treatment, clinical trials are informing on treatment efficacy and safety, and longitudinal studies of neurological, cognitive and quality of life outcomes are informing on the impact of these diseases. We provide updates to assist providers caring for these children. RECENT FINDINGS: The recent 2017 McDonald Criteria for MS provide a simplified means to confirm diagnosis at onset and over time, and have been shown to be equally applicable for POMS. MRI analyses demonstrate that brain volume is reduced at onset, and that both volumetric and tissue integrity measures decline over time, indicating that POMS shares the degenerative aspects that also characterize adult-onset disease. The presence of myelin oligodendrocyte glycoprotein (MOG) antibodies at onset is detected in more than 50% of children with acute disseminated encephalomyelitis. When persistent over time, they are associated with relapsing disease. The first randomized clinical trials of disease supports superiority of fingolimod over subcutaneous interferon beta 1a, and demonstrated a favorable safety profile. Finally, while Expanded Disability Status Scale (EDSS) scores remain low in the first 10 years post-onset, POMS is associated with high rates of patient-reported fatigue and reduced engagement in exercise and carries a risk for cognitive impairment. The past 15 years have borne witness to a marked expansion in recognition and research in POMS. There are now more specific diagnostic criteria, antibodies to CNS proteins appear to define diagnostically distinct disorders, clinical trials have successfully launched and one has completed, and we are gaining increasing appreciation of the impact of MS and related disorders on the lived experience of children and adolescents.

The Persisting Significance of Oligoclonal Bands in the Dawning Era of Kappa Free Light Chains for the Diagnosis of Multiple Sclerosis.

The latest revision of the McDonald criteria of 2017 considers the evidence of an intrathecal immunoglobulin (IgG) synthesis as a diagnostic criterion for dissemination in time in multiple sclerosis. While the detection of oligoclonal bands is considered as the gold standard, determination of kappa free light chains might be a promising tool as a less technically demanding and cost saving method. However, data on the direct comparison between kappa free light chains and oligoclonal bands are limited and no study to date has used the highly sensitive method of polyacrylamide gels with consecutive silver staining for the demonstration of oligoclonal bands. Furthermore, the impact of the revised McDonald criteria of 2017 on the role of kappa free light chains as a biomarker has not been investigated. Nephelometry was used to determine kappa free light chains in cerebrospinal fluid (CSF) and serum from 149 patients with their first demyelinating event between 2010 and 2015. Clinical data, kappa free light chains, and oligoclonal band status were compared at the time of initial diagnosis and after follow-up to identify converters from clinically isolated syndrome to multiple sclerosis. An elevated kappa free light chain index (>5.9) was found in 79/83 patients (95%) with multiple sclerosis diagnosed at baseline, slightly less frequent than oligoclonal bands (98.8%). 18/25 (72%) patients who converted from clinically isolated syndrome to multiple sclerosis showed an elevated kappa free light chain index compared to 20/25 (80%) patients with positive oligoclonal bands. In patients with stable clinically isolated syndrome 7/41 (17%) displayed an elevated kappa free light chain index against 11/41 (27%) oligoclonal band positive patients. Only two patients with stable clinically isolated syndrome showed an elevated kappa free light chain index but were oligoclonal bands negative. In conclusion, determination of the kappa free light chain index is a promising diagnostic approach to assess intrathecal immunoglobulin synthesis in multiple sclerosis. Nevertheless, oligoclonal bands are highly prevalent in multiple sclerosis and can detect an intrathecal synthesis of IgG even when the kappa free light chain index is below the threshold. We consider sequential use of both methods as reasonable.

[Diagnosis of multiple sclerosis: A review of the 2017 revisions of the McDonald criteria]. / A sclerosis multiplex diagnosztikája: Összefoglaló a McDonald-kritériumok 2017-es felülvizsgálatáról.

The revolutionary progress of research in neuroimmu-nology has led to the introduction of disease modifying therapies in multiple sclerosis at the end of the last century. The International Panel on Diagnosis of Multiple Sclerosis originally proposed the 2001 McDonald criteria to facilitate the diagnosis of MS in patients with the first objective neurological symptom(s) suggesting demyelinating event, when magnetic resonance imaging is integrated with clinical and other paraclinical diagnostic methods. New terms have been introduced to substitute clinical information by MRI: dissemination in space - indicating a multifocal central demyelinating process and dissemination in time - indicating the development of new CNS lesions over time. The criteria for diagnosis of Multiple Sclerosis have continuously evolved, they were modified in 2005 and 2010 allowing for an earlier and more accurate diagnosis of MS over time, and they provided the most up-to-date guidance for clinicians and researchers. The last recommended revisions relied entirely on available evidence, and not on expert opinion thereby reducing the risk of the misdiagnosis. The 2017 McDonald criteria continue to apply primarily to patients experiencing a typical, clinically isolated syndrome. In this review, we provide an overview of the recent 2017 revisions to the criteria of dissemination in space and time with the importance of the presence of CSF-specific oligoclonal bands; keeping fully in mind that there is no better explanation for symptoms than diagnosis of MS. In the future, validation of the 2017 McDonald criteria will be needed in diverse populations. Further investigations are required on the value of new MRI approaches, on optic nerve involvement, on evoked potential and optical coherence tomography, in order to assess their possible contribution to diagnostic criteria.

MOG-IgG in NMO and related disorders: a multicenter study of 50 patients. Part 2: Epidemiology, clinical presentation, radiological and laboratory features, treatment responses, and long-term outcome.

BACKGROUND: A subset of patients with neuromyelitis optica spectrum disorders (NMOSD) has been shown to be seropositive for myelin oligodendrocyte glycoprotein antibodies (MOG-IgG). OBJECTIVE: To describe the epidemiological, clinical, radiological, cerebrospinal fluid (CSF), and electrophysiological features of a large cohort of MOG-IgG-positive patients with optic neuritis (ON) and/or myelitis (n = 50) as well as attack and long-term treatment outcomes. METHODS: Retrospective multicenter study. RESULTS: The sex ratio was 1:2.8 (m:f). Median age at onset was 31 years (range 6-70). The disease followed a multiphasic course in 80 % (median time-to-first-relapse 5 months; annualized relapse rate 0.92) and resulted in significant disability in 40 % (mean follow-up 75 ± 46.5 months), with severe visual impairment or functional blindness (36 %) and markedly impaired ambulation due to paresis or ataxia (25 %) as the most common long-term sequelae. Functional blindess in one or both eyes was noted during at least one ON attack in around 70 %. Perioptic enhancement was present in several patients. Besides acute tetra-/paraparesis, dysesthesia and pain were common in acute myelitis (70 %). Longitudinally extensive spinal cord lesions were frequent, but short lesions occurred at least once in 44 %. Fourty-one percent had a history of simultaneous ON and myelitis. Clinical or radiological involvement of the brain, brainstem, or cerebellum was present in 50 %; extra-opticospinal symptoms included intractable nausea and vomiting and respiratory insufficiency (fatal in one). CSF pleocytosis (partly neutrophilic) was present in 70 %, oligoclonal bands in only 13 %, and blood-CSF-barrier dysfunction in 32 %. Intravenous methylprednisolone (IVMP) and long-term immunosuppression were often effective; however, treatment failure leading to rapid accumulation of disability was noted in many patients as well as flare-ups after steroid withdrawal. Full recovery was achieved by plasma exchange in some cases, including after IVMP failure. Breakthrough attacks under azathioprine were linked to the drug-specific latency period and a lack of cotreatment with oral steroids. Methotrexate was effective in 5/6 patients. Interferon-beta was associated with ongoing or increasing disease activity. Rituximab and ofatumumab were effective in some patients. However, treatment with rituximab was followed by early relapses in several cases; end-of-dose relapses occurred 9-12 months after the first infusion. Coexisting autoimmunity was rare (9 %). Wingerchuk's 2006 and 2015 criteria for NMO(SD) and Barkhof and McDonald criteria for multiple sclerosis (MS) were met by 28 %, 32 %, 15 %, 33 %, respectively; MS had been suspected in 36 %. Disease onset or relapses were preceded by infection, vaccination, or pregnancy/delivery in several cases. CONCLUSION: Our findings from a predominantly Caucasian cohort strongly argue against the concept of MOG-IgG denoting a mild and usually monophasic variant of NMOSD. The predominantly relapsing and often severe disease course and the short median time to second attack support the use of prophylactic long-term treatments in patients with MOG-IgG-positive ON and/or myelitis.

Evolution of diagnostic criteria for multiple sclerosis.

Multiple sclerosis is a chronic demyelinating disease of the central nervous system that occurs primarily in young adults. There is no single diagnostic test to recognize the disease. The diagnostic criteria, based on clinical examination and laboratory tests, have changed considerably over time. The first guidelines involved only the results of the patient's neurological examination. The diagnostic criteria developed by Poser in 1983 were based largely on the results of additional tests, including visual evoked potentials and analysis of cerebrospinal fluid. The McDonald criteria, developed in 2001 and updated in 2005 and 2010, reflected the diagnostic breakthrough caused by widespread use of magnetic resonance imaging (MRI). Currently, the diagnosis depends largely on the results of the MRI examination. An early diagnosis is particularly important for starting disease-modifying treatments.

Application and a proposed modification of the 2010 McDonald criteria for the diagnosis of multiple sclerosis in a Canadian cohort of patients with clinically isolated syndromes.

BACKGROUND: The 2005 and 2010 McDonald criteria utilize magnetic resonance imaging (MRI) to provide evidence of disease dissemination in space (DIS) and time (DIT) for the diagnosis of multiple sclerosis (MS) in patients who have clinically isolated syndromes (CIS). METHODS: Data from 109 CIS patients not satisfying the 2005 criteria at entry into a randomized controlled minocycline trial were analyzed to determine the proportion who would have been diagnosed with MS at screening based on 2010 criteria. The impact of including symptomatic, as well as asymptomatic, MRI lesions to confirm DIT was also explored. RESULTS: Thirty percent (33/109) of patients, retrospectively, met the 2010 criteria for a diagnosis of MS at baseline. When both symptomatic and asymptomatic lesions were used to confirm DIT, three additional patients met the 2010 criteria. There was a significant 10.1% increase in the proportion of patients who met the 2010 DIS criteria, compared with the 2005 DIS criteria; however, two patients satisfied the 2005 DIS but not 2010 DIS criteria. CONCLUSION: Using 2010 McDonald criteria, 30% of the CIS patients could be diagnosed with MS using a single MRI scan. Inclusion of symptomatic lesions in the DIT criteria further increases this proportion to 33%.

Real-life evaluation of the 2017 McDonald criteria for relapsing-remitting multiple sclerosis after a clinically isolated syndrome confirms a gain in time-to-diagnosis.

BACKGROUND: Previous cohort studies evaluating the performances of the McDonald criteria suffered from bias regarding real-life conditions. We aimed to evaluate the probability of diagnosing relapsing-remitting multiple sclerosis (MS) at several timepoints from the first medical evaluation and the gain in time-to-diagnosis with the 2017 McDonald criteria compared with the 2001, 2005 and 2010 versions in real life. METHODS: Patients with a first demyelinating event suggestive of MS between 2002 and 2020 were included in the ReLSEP, an exhaustive and prospectively incremented registry of MS patients in North-Eastern France. We estimated the probability of being positive at the first medical evaluation and at five timepoints according to the four versions of criteria using Kaplan-Meier estimators and Cox models. RESULTS: A total of 2220 patients were followed up for a median of 7.1 years. At baseline, 31.7%, 32.1%, 36.6% and 54.0% of patients, respectively, fulfilled the 2001, 2005, 2010 and 2017 McDonald criteria. Using the 2017 criteria, the gain in time-to-diagnosis was 3.7 months compared with the 2010 criteria. The presence of intrathecal synthesis of immunoglobulin G in the McDonald 2017 criteria led to a 1.8-month reduction in median time-to-diagnosis compared to a version of McDonald 2017 without this criteria. CONCLUSIONS: In real-life, the 2017 McDonald criteria revision undoubtedly shortened time-to-diagnosis.

Multiple Sclerosis Part 1: Essentials and the McDonald Criteria.

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system (CNS) characterized by relapsing-remitting or progressive neurologic symptoms and focal white matter lesions. The hallmark of the disease is the dissemination of CNS lesions in space and time, which is defined by the McDonald criteria. MRI is an essential diagnostic and prognostic biomarker for MS which can evaluate the entire CNS. MS mimics must be excluded before a diagnosis of MS is made.

Clinical and paraclinical characteristics of optic neuritis in the context of the McDonald criteria 2017.

Optic neuritis is often an initial symptom in multiple sclerosis (MS) or clinically isolated syndrome (CIS), yet comprehensive studies using the 2017 McDonald criteria for MS are scarce. Patient records from our academic centre (2010-2018) were reviewed. Using the 2017 McDonald criteria, three groups were formed: MS optic neuritis (optic neuritis with confirmed MS), CIS optic neuritis (optic neuritis without confirmed MS) and suspected optic neuritis (sON). We compared clinical and paraclinical findings among the groups to identify predictors for CIS- or MS-optic neuritis. The study included 129 MS, 108 CIS, and 44 sON cases. The combination of visual impairment, dyschromatopsia, and retrobulbar pain was observed in 47% of MS patients, 42% of CIS patients, and 30% of sON patients. Dyschromatopsia was the strongest indicator of MS or CIS diagnosis in the backward regression model. 56% of MS patients had relative afferent pupillary defect, 61% optic nerve anomalies within magnetic resonance imaging, and 81% abnormal visual evoked potentials. Our results emphasize the challenges in diagnosing optic neuritis, as not all patients with objectively diagnosed MS exhibit the triad of typical symptoms. To address potentially missing clinical features, incorporating additional paraclinical findings is proposed.

Differential diagnosis between multiple sclerosis and leukodystrophies - A scoping review.

Multiple Sclerosis (MS) is an autoimmune demyelinating disease of the central nervous system (CNS) characterized by damage to the myelin sheaths of oligodendrocytes. Currently, there is no specific biomarker to identify the disease; however, a diagnostic criterion has been established based on patient's clinical, laboratory, and imaging characteristics, which assists in identifying this condition. The primary method for diagnosing MS is the McDonald criteria, first described in 2001 and revised in the years 2005, 2012, and 2017. These criteria have been continuously reviewed to enhance specificity and sensitivity in the diagnosis of MS, thereby reducing errors in its differential diagnosis. An important differential diagnosis that shares overlapping features with MS, mainly the progressive forms, are leukodystrophies with demyelination as underlying pathology. Leukodystrophies comprise a rare group of genetically determined disorders that lead to either demyelination or hypomyelination of the central nervous system that can result neuroimaging changes as well as clinical findings similar to those observed in MS. Thus, systematic evaluation encompassing clinical presentation, neuroimaging findings, and laboratory metrics proves indispensable for a differential diagnosis. As such, this study aimed to establish, clearly and objectively, the similarities and differences between MS and the main demyelinating leukodystrophies. The study analyzed the parameters of the McDonald criteria, including clinical, laboratory, and magnetic resonance imaging aspects, as found in patients with leukodystrophies through scoping literature review. The data were compared with the determinations of the revised 2017 McDonald criteria to facilitate the differential diagnosis of these diseases in clinical practice.

Multiple Sclerosis: Clinical Update and Clinically-Oriented Radiologic Reporting.

Multiple sclerosis (MS) is a chronic inflammatory disease of the nervous system. MR imaging findings play an integral part in establishing diagnostic hallmarks of the disease during initial diagnosis and evaluating disease status. Multiple iterations of diagnostic criteria and consensus guidelines are put forth by various expert groups incorporating imaging of the brain and spine, and efforts have been made to standardize imaging protocols for MS. Emerging ancillary imaging findings have also attracted increasing interests and should be sought for on radiologic examination. In this paper, the authors review the clinical guidelines and approach to imaging of MS and related disorders, focusing on clinically impactful image interpretation and MR imaging reporting.