Misdiagnosis of Multiple Sclerosis: Frequency, Causes, Effects, and Prevention

Misdiagnosis and underdiagnosis of multiple sclerosis: A systematic review and meta-analysis

BACKGROUND

Diagnostic errors in multiple sclerosis (MS) impact patients and healthcare systems.

OBJECTIVES

This study aimed to determine the prevalence of MS misdiagnosis and underdiagnosis, time delay in reaching a correct diagnosis and potential impact of sex.

METHODS

Systematic review and meta-analysis on MS diagnostic errors.

RESULTS

Out of 3910 studies, we included 62 for a qualitative synthesis and 24 for meta-analyses. Frequency of misdiagnosis (incorrect assignment of an MS diagnosis) ranged from 5% to 41%, with a pooled proportion based on six studies of 15% (95% CI: 9%-26%, n = 1621). The delay to rectify a misdiagnosis ranged from 0.3 to 15.9 years. Conversely, underdiagnosis (unrecognized diagnosis of MS) ranged from 3% to 58%, with a pooled proportion in four studies of 36% (95% CI: 20%-55%, n = 728). Pooling seven studies comprising 2851 individuals suggested a diagnostic delay to establish a correct MS diagnosis of 17.3 months (95% CI: 11.9-22.7) in patients underdiagnosed. In a meta-analysis of five studies, women were 2.1 times more likely to be misdiagnosed with MS compared to men (odds ratio, 95% CI: 1.53-2.86).

CONCLUSION

This study provides summary-level evidence for the high prevalence of MS misdiagnosis and underdiagnosis. Future studies are needed to understand the causes of these diagnostic challenges in MS care.

One or many labels? a longitudinal qualitative study of patients' journey to diagnosis at a specialist NHS Postural Tachycardia Syndrome (PoTS) clinic

OBJECTIVES

Postural Tachycardia Syndrome (PoTS) is a poorly understood syndrome of multiple disabling symptoms. This study explored the process of seeking a diagnosis of PoTS. Analysis focused on changes before and after participants' first appointment with a national PoTS clinic, and explored whether a diagnosis is beneficial in the context of multiple co-occurring conditions and an absence of licenced treatments.

DESIGN

A longitudinal, qualitative study.

METHODS

Participants (n = 15) in this nested qualitative study were recruited from a larger study of people who had been newly referred to a National specialist NHS Cardiology PoTS service. Semi-structured interviews were conducted remotely before, and 6 months after their first appointment with the clinic. Data was analysed longitudinally and inductively using Reflexive Thematic Analysis.

RESULTS

Three overarching themes were identified: "Slowly moving forward and finding positive gains", "Needing more pieces of the puzzle to see the bigger picture", and "The value and impact of investigations". Findings suggested that not much had changed in the 6 months between interviews. Participants were moving forward in terms of diagnoses, treatment and adjustment following their appointment, but many were still seeking further clarity and possible diagnoses. Investigations, appointments, and new-found problems, continued to have a substantial impact over time.

CONCLUSIONS

The journey to diagnosis for patients with suspected PoTS appeared to promote acceptance of self, and of limitations posed by symptoms. However, many participants continued their search for an explanation for every symptom experience, and this may become increasingly complex, the more labels that have been acquired. Lack of clarity contributed to ongoing difficulties for this patient group alongside fraught relations with health care professionals (HCPs). A more coherent, integrated approach which is communicated clearly to patients is recommended.

[The central vein sign in the differential diagnosis of multiple sclerosis]

OBJECTIVE

To carry out a clinical and radiological assessment of the central vein sign (CVS) as a diagnostic marker for multiple sclerosis (MS) and other demyelinating and non-demyelinating diseases with focal brain damage, using clinical and laboratory examination data, as well as MRI.

MATERIAL AND METHODS

The results of clinical and neuroradiological examination of 107 patients diagnosed with MS or with other diseases accompanied by focal brain damage according to MRI data were analyzed.

RESULTS

CVS is a sensitive but low-specific diagnostic marker of MS. According to our data, the sensitivity and specificity of 40 and 50% of the threshold of perivenular lesions in the diagnosis of MS are the same and amount to 100% and 39.4%, respectively. Neither the type of MS course, nor the severity of the course, nor the intake of DMT (disease modifying treatment), affect the proportion of foci with CVS. The spread of the proportion of foci with CVS in patients with MS was 60-100%. The proportion of foci with CVS is below 40 and 50% of the threshold in patients with demyelinating and non-demyelinating diseases (NMOSD, migraine, systemic lupus erythematosus, Susak disease, CLIPPERS), which allows for differential diagnosis with MS. The proportion of foci with CVS comparable to MS in patients with acute disseminated encephalomyelitis, small vessel disease, as well as in patients with radiologically isolated syndrome does not allow using this symptom in the differential diagnosis of these conditions.

CONCLUSION

The use of CVS as a diagnostic marker of MS is possible only in combination with the already existing diagnostic criteria of MS.

Adult inflammatory leukoencephalopathies

Inflammatory white matter disorders may commonly mimic genetic leukoencephalopathies. These include atypical presentations of common conditions, such as multiple sclerosis, together with rare inflammatory disorders. A structured approach to such cases is essential, together with judicious use of the many available diagnostic biomarkers. The potential for such conditions to respond to immunotherapy emphasizes the importance of an accurate and prompt diagnosis in improving patient outcomes.

Dynamic changes in patient admission and their disabilities in multiple sclerosis and neuromyelitis optica: A Japanese nationwide administrative data study

BACKGROUND

The real-world data evidences how establishment of neuromyelitis optica (NMO) disease concept and development disease modifying therapy affect the patients with multiple sclerosis (MS) and NMO are lacking. The aim of this study is to clarify the diachronic trend of the severity and admissions of patients with MS and NMO.

METHODS

We retrospectively investigated the trends in admissions, treatments, and disabilities in the patients with MS and NMO using the Japanese administrative data between 2012 and 2017.

RESULTS

We analyzed acute stage 9545 and 2035 admissions in each 6100 MS and 1555 NMO patients. The annual number of admission in MS significantly decreased in 6 years; however, those in NMO consistently increased. The patient proportion with lower disability was significantly increased in MS and NMO. These trends were especially observed in patients admitted to centralized hospitals with more active treatments, such as second-line disease modifying therapy for MS and plasmapheresis for NMO. Patients with NMO using DMT for MS diminished in 6 years.

CONCLUSION

A gradual improvement of disability in patients with MS and NMO was observed, probably due to advanced treatments, increased NMO awareness, and decreased misdiagnosis, which seems to be the key for better prognosis in MS and NMO.

Misdiagnosis in multiple sclerosis in a Brazilian reference center: Clinical, radiological, laboratory profile and failures in the diagnostic process-Cohort study

BACKGROUND

Multiple sclerosis misdiagnosis remains a problem despite the well-validated McDonald 2017. For proper evaluation of errors in the diagnostic process that lead to misdiagnosis, it is adequate to incorporate patients who are already under regular follow-up at reference centers of demyelinating diseases.

OBJECTIVES

To evaluate multiple sclerosis misdiagnosis in patients who are on follow-up at a reference center of demyelinating diseases in Brazil.

METHODS

We designed an observational study including patients in regular follow-up, who were diagnosed with multiple sclerosis at our specialized outpatient clinic in the Hospital of Clinics in the University of Sao Paulo, from 1996 to 2021, and were reassessed for misdiagnosis in 2022. We evaluated demographic information, clinical profile, and complementary exams and classified participants as "established multiple sclerosis," "non-multiple sclerosis, diagnosed," and "non-multiple sclerosis, undiagnosed." Failures in the diagnostic process were assessed by the modified Diagnostic Error Evaluation and Research tool.

RESULTS

A total of 201 patients were included. After analysis, 191/201 (95.02%) participants were confirmed as "established multiple sclerosis," 5/201 (2.49%) were defined as "non-multiple sclerosis, diagnosed," and 5/201 (2.49%) were defined as "non-multiple sclerosis, undiagnosed."

CONCLUSIONS

Multiple sclerosis misdiagnosis persists in reference centers, emphasizing the need for careful interpretation of clinical findings to prevent errors.

Secondary Central Nervous System Demyelinating Disorders in the Elderly: A Narrative Review

Secondary demyelinating diseases comprise a wide spectrum group of pathological conditions and may either be attributed to a disorder primarily affecting the neurons or axons, followed by demyelination, or to an underlying condition leading to secondary damage of the myelin sheath. In the elderly, primary demyelinating diseases of the central nervous system (CNS), such as multiple sclerosis, are relatively uncommon. However, secondary causes of CNS demyelination may often occur and in this case, extensive diagnostic workup is usually needed. Infectious, postinfectious, or postvaccinal demyelination may be observed, attributed to age-related alterations of the immune system in this population. Osmotic disturbances and nutritional deficiencies, more commonly observed in the elderly, may lead to conditions such as pontine/extrapontine myelinolysis, Wernicke encephalopathy, and demyelination of the posterior columns of the spinal cord. The prevalence of malignancies is higher in the elderly, sometimes leading to radiation-induced, immunotherapy-related, or paraneoplastic CNS demyelination. This review intends to aid clinical neurologists in broadening their diagnostic approach to secondary CNS demyelinating diseases in the elderly. Common clinical conditions leading to secondary demyelination and their clinical manifestations are summarized here, while the current knowledge of the underlying pathophysiological mechanisms is additionally presented.

[Diagnostic work-up, findings, and documentation of multiple sclerosis]

BACKGROUND

Although multiple sclerosis is the most common chronic inflammatory demyelinating disease of the central nervous system, the rate of misdiagnosis in clinical practice is high. This is usually due to the inadequate application of the McDonald criteria and misinterpretation of images.

OBJECTIVE

This review focuses on typical clinical symptoms, choice of magnetic resonance imaging (MRI) sequences, correct application of the McDonald criteria, and finally interpretation of the images.

The borderland of multiple sclerosis and functional neurological disorder: A call for clinical research and vigilance

BACKGROUND AND PURPOSE

Functional neurological disorders (FNDs) have attracted much attention from the neurological medical community over the last decades as new developments in neurosciences have reduced stigma around these by showing brain network dysfunctions. An overlap with other neurological conditions such as multiple sclerosis (MS) is well known by clinicians but there is a lack of clinical and fundamental research in this field to better define diagnosis and therapeutic decisions, as well as a lack of deep understanding of the underlying pathophysiology.

AIM

We aimed to provide a critical commentary on the state of knowledge about the borderland between FNDs and MS.

METHODS

We based our commentary on a joint point of view between an FND specialist and an MS expert.

RESULTS

A brief review of the previous literature and relevant new studies covering the overlap between FNDs and MS is presented, along with suggestions for future research directions.

CONCLUSION

There are clear diagnostic criteria for both FNDs and MS and a strict application of these will help better diagnosis and prevent unnecessary treatment escalation in MS or absence of referral to multimodal therapy in FND. Better teaching of younger neurologists is needed as well as prospective research focusing on pathophysiology.

NMOSD-Diagnostic Dilemmas Leading towards Final Diagnosis

(1) Background: The emergence of white matter lesions in the central nervous system (CNS) can lead to diagnostic dilemmas. They are a common radiological symptom and their patterns may overlap CNS or systemic diseases and provoke underdiagnosis or misdiagnosis. The aim of the study was to assess factors influencing the underdiagnosis of neuromyelitis optica spectrum disorder (NMOSD) as well as to estimate NMOSD epidemiology in Lubelskie voivodeship, Poland. (2) Methods: This retrospective study included 1112 patients, who were made a tentative or an established diagnosis of acute or subacute onset of neurological deficits. The evaluation was based on medical history, neurological examination, laboratory and radiographic results and fulfilment of diagnosis criteria. (3) Results: Up to 1.62 percent of patients diagnosed with white matter lesions and up to 2.2% of the patients previously diagnosed with MS may suffer from NMOSD. The duration of delayed diagnosis is longer for males, despite the earlier age of onset. Seropositive cases for antibodies against aquaporin-4 have worse prognosis for degree of disability. (4) Conclusions: Underdiagnosis or misdiagnosis in NMOSD still remains a problem in clinical practice and has important implications for patients. The incorrect diagnosis is caused by atypical presentation or NMOSD-mimics; however, covariates such as gender, onset and diagnosis age may also have an influence.

Adult Hereditary White Matter Diseases With Psychiatric Presentation: Clinical Pointers and MRI Algorithm to Guide the Diagnostic Process

OBJECTIVE

The investigators aimed to provide clinical and MRI guidelines for determining when genetic workup should be considered in order to exclude hereditary leukoencephalopathies in affected patients with a psychiatric presentation.

METHODS

A systematic literature review was conducted, and clinical cases are provided. Given the central role of MRI pattern recognition in the diagnosis of white matter disorders, the investigators adapted an MRI algorithm that guides the interpretation of MRI findings and thus directs further investigations, such as genetic testing.

RESULTS

Twelve genetic leukoencephalopathies that can present with psychiatric symptoms were identified. As examples of presentations that can occur in clinical practice, five clinical vignettes from patients assessed at a referral center for adult genetic leukoencephalopathies are provided.

CONCLUSIONS

Features such as drug-resistant symptoms, presence of long-standing somatic features, trigger events, consanguinity, and positive family history should orient the clinician toward diagnostic workup to exclude the presence of a genetic white matter disorder. The identification of MRI white matter abnormalities, especially when presenting a specific pattern of involvement, should prompt genetic testing for known forms of genetic leukoencephalopathies.

The central vein sign helps in differentiating multiple sclerosis from its mimickers: lessons from Fabry disease

OBJECTIVES

Although the use of specific MRI criteria has significantly increased the diagnostic accuracy of multiple sclerosis (MS), reaching a correct neuroradiological diagnosis remains a challenging task, and therefore the search for new imaging biomarkers is crucial. This study aims to evaluate the incidence of one of the emerging neuroradiological signs highly suggestive of MS, the central vein sign (CVS), using data from Fabry disease (FD) patients as an index of microvascular disorder that could mimic MS.

METHODS

In this retrospective study, after the application of inclusion and exclusion criteria, MRI scans of 36 FD patients and 73 relapsing-remitting (RR) MS patients were evaluated. Among the RRMS participants, 32 subjects with a disease duration inferior to 5 years (early MS) were also analyzed. For all subjects, a Fazekas score (FS) was recorded, excluding patients with FS = 0. Different neuroradiological signs, including CVS, were evaluated on FLAIR T2-weighted and spoiled gradient recalled echo sequences.

RESULTS

Among all the recorded neuroradiological signs, the most striking difference was found for the CVS, with a detectable prevalence of 78.1% (57/73) in RRMS and of 71.4% (25/32) in early MS patients, while this sign was absent in FD (0/36).

CONCLUSIONS

Our results confirm the high incidence of CVS in MS, also in the early phases of the disease, while it seems to be absent in conditions with a different etiology. These results corroborate the possible role of CVS as a useful neuroradiological sign highly suggestive of MS.

KEY POINTS

• The search for new imaging biomarkers is crucial to achieve a correct neuroradiological diagnosis of MS. • The CVS shows an incidence superior to 70% in MS patients, even in the early phases of the disease, while it appears to be absent in FD. • These findings further corroborate the possible future central role of CVS in distinguishing between MS and its mimickers.

Recurrent ataxia and dysarthria in myelin oligodendrocyte glycoprotein antibody-associated disorder

The spectrum of central nervous system demyelinating disorders is vast and heterogeneous and, often, with overlapping clinical presentations. Misdiagnosis might occur in some cases with serious therapeutic repercussions. However, introduction of several new biomarkers such as aquaporin-4 IgG and myelin oligodendrocyte glycoprotein IgG has made distinction between diseases such as multiple sclerosis and myelin oligodendrocyte glycoprotein antibody-associated disorder easier. Here, we report a case of a 15-year-old male patient with subacute multifocal neurological presentation without encephalopathy, eventually diagnosed as myelin oligodendrocyte glycoprotein antibody-associated disorder.

Central vein sign: A diagnostic biomarker in multiple sclerosis (CAVS-MS) study protocol for a prospective multicenter trial

The specificity and implementation of current MRI-based diagnostic criteria for multiple sclerosis (MS) are imperfect. Approximately 1 in 5 of individuals diagnosed with MS are eventually determined not to have the disease, with overreliance on MRI findings a major cause of MS misdiagnosis. The central vein sign (CVS), a proposed MRI biomarker for MS lesions, has been extensively studied in numerous cross sectional studies and may increase diagnostic specificity for MS. CVS has desirable analytical, measurement, and scalability properties. "Central Vein Sign: A Diagnostic Biomarker in Multiple Sclerosis (CAVS-MS)" is an NIH-supported, 2-year, prospective, international, multicenter study conducted by the North American Imaging in MS Cooperative (NAIMS) to evaluate CVS as a diagnostic biomarker for immediate translation into clinical care. Study objectives include determining the concordance of CVS and McDonald Criteria to diagnose MS, the sensitivity of CVS to detect MS in those with typical presentations, and the specificity of CVS among those with atypical presentations. The study will recruit a total of 400 participants (200 with typical and 200 with atypical presentations) across 11 sites. T2*-weighted, high-isotropic-resolution, segmented echo-planar MRI will be acquired at baseline and 24 months on 3-tesla scanners, and FLAIR* images (combination of FLAIR and T2*) will be generated for evaluating CVS. Data will be processed on a cloud-based platform that contains clinical and CVS rating modules. Imaging quality control will be conducted by automated methods and neuroradiologist review. CVS will be determined by Select6* and Select3* lesion methods following published criteria at each site and by central readers, including neurologists and neuroradiologists. Automated CVS detection and algorithms for incorporation of CVS into McDonald Criteria will be tested. Diagnosis will be adjudicated by three neurologists who served on the 2017 International Panel on the Diagnosis of MS. The CAVS-MS study aims to definitively establish CVS as a diagnostic biomarker that can be applied broadly to individuals presenting for evaluation of the diagnosis of MS.

Persons with suspicious onset of multiple sclerosis but with undetermined diagnosis had persistent lower cognition and reduced quality of life

BACKGOUND

Differential diagnosis of multiple sclerosis (MS) includes a variety of disorders and misdiagnosis is common.

OBJECTIVE

To follow-up persons with suspected onset of MS but in whom the diagnostic investigation was negative.

METHODS

In a prospective study including 271 persons with clinical features of suspected MS onset, 136 persons were diagnosed with MS or clinically isolated syndrome (PwMS), 46 had other disorders, and 89 persons had a negative diagnostic work-up, i.e. persons with undetermined diagnosis (PwUD). They underwent diagnostic reassessment, and those who remained without a diagnosis were investigated for signs of pathology including cognitive tests and assessments of quality of life (QoL). Results were compared with those of PwMS and 24 age and sex matched healthy controls (HC).

RESULTS

After reassement 55 (20%) persons still had undetermined diagnosis (PwUD). They had similar age and gender distribution as PwMS. In 76% of PwUD, the suspected clinical onset included sensory symptoms. PwUD and PwMS scored similarly in cognitive tests and QoL but significantly lower than HC. At 3 years follow-up, PwMS and PwUD improved in most test parameters, but PwUD scored lower than PwMS in cognition.

CONCLUSION

PwUD constituted the dominating differential diagnosis in persons with suspected clinical onset of MS. QoL and cognition were comparable with those of PwMS but significantly lower than in HC.

Myelin oligodendrocyte glycoprotein antibody-associated disorders: clinical spectrum, diagnostic evaluation, and treatment options

Inflammatory or immune-mediated demyelinating central nervous system (CNS) syndromes include a broad spectrum of clinical phenotype and different overlapping diseases. Antibodies against myelin oligodendrocyte glycoprotein (MOG-Ab) have been found in some cases of these demyelinating diseases, particularly in children. MOG-Ab is associated with a wider clinical phenotype not limited to neuromyelitis optica spectrum disorder, with most patients presenting with optic neuritis, acute disseminated encephalomyelitis (ADEM) or ADEM-like encephalitis with brain demyelinating lesions, and/or myelitis. Using specific cell-based assays, MOG-Ab is becoming a potential biomarker of inflammatory demyelinating disorders of the CNS. A humoral immune reaction against MOG was recently found in monophasic diseases and recurrent/multiphasic clinical progression, particularly in pediatric patients. This review summarizes the data regarding MOG-Ab as an impending biological marker for discriminating between these diverse demyelinating CNS diseases and discusses recent developments, clinical applications, and findings regarding the immunopathogenesis of MOG-Ab-associated disorders.

The frequency and characteristics of MS misdiagnosis in patients referred to the multiple sclerosis centre of Catalonia

Background:

Multiple sclerosis (MS) misdiagnosis may cause physical and emotional damage to patients.

Objectives:

The objective of this study is to determine the frequency and characteristics of MS misdiagnosis in patients referred to the Multiple Sclerosis Centre of Catalonia.

Methods:

We designed a prospective study including all new consecutive patients referred to our centre between July 2017 and June 2018. Instances of misdiagnosis were identified, and referral diagnosis and final diagnosis were compared after 1 year of follow-up. Association of misdiagnosis with magnetic resonance imaging (MRI) findings, presence of comorbidities and family history of autoimmunity were assessed.

Results:

A total of 354 patients were referred to our centre within the study period, 112 (31.8%) with ‘established MS’. Misdiagnosis was identified in eight out of 112 cases (7.1%). MRI identified multifocal white matter lesions, deemed non-specific or not suggestive of MS in all misdiagnosed cases. Patients with MS misdiagnosis had more comorbidities in general than patients with MS ( p = 0.026) as well as a personal history of autoimmunity ( p < 0.001).

Conclusion:

A low frequency of MS misdiagnosis was found in our clinical setting. Multifocal non-specific white matter lesions in referral MRI examinations and the presence of comorbidities, including a personal history of autoimmunity, seem to be contributing factors to misdiagnosis.

Biomechanical muscle stiffness measures of extensor digitorum explain potential mechanism of McArdle sign

BACKGROUND

McArdle sign is a phenomenon of impaired gait and muscle weakness that occurs with neck flexion, immediately reversible with neck extension. A recent report measured the specificity of this sign for multiple sclerosis by measuring differences in peak torque of the extensor digitorum between neck extension and flexion.

METHODS

This substudy included 73 participants (29 multiple sclerosis, 20 non-multiple sclerosis myelopathies, 5 peripheral nerve disorders, and 19 healthy controls). The effect of neck position was assessed on muscle stiffness and neuromechanical error of the extensor digitorum.

FINDINGS

Patients with multiple sclerosis had greater neuromechanical error (sum of squared error of prediction) compared to controls (P = 0.023) and non-multiple sclerosis myelopathies (P = 0.003). Neuromechanical error also provided improved sensitivity/specificity of McArdle sign. Peak torque, muscle stiffness, and neuromechanical error could distinguish multiple sclerosis from other myelopathies with 80% specificity and 97% sensitivity (AUC = 0.95).

INTERPRETATION

A decrease in muscle stiffness and neuromechanical error in neck flexion compared to extension are additional indicators for a diagnosis of multiple sclerosis. Analysis of muscle stiffness may provide insights into the pathophysiology of this specific clinical sign for multiple sclerosis. Furthermore, muscle stiffness may provide an additional accurate, simple assessment to evaluate multiple sclerosis therapeutic interventions and disease progression.

Clinical and Radiological Characteristics of Neuromyelitis Optica Spectrum Disorder: The Experience from Saudi Arabia

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) is a rare autoimmune astrocytopathy that affects several regions of the central nervous system (CNS) with a predilection for the optic nerves and spinal cord. Epidemiological studies of NMOSD are uncommon in the Middle East and up-to-date, there are no such data from Saudi Arabia. In this study, we aim to study the clinical pattern of NMOSD patients in Saudi Arabia.

METHODS

A retrospective multi-center observational study was conducted at King Abdulaziz Medical City in Jeddah and Riyadh, Saudi Arabia. The inclusion criteria consisted of all the patients with either neuromyelitis optica according to the 2006 criteria or NMOSD according to the 2015 criteria. The study period was 20 years.

RESULTS

A total of 23 patients were included in the study. Four were males (17.4%) and 19 were females (82.6%). The attack type was optic neuritis in 3 patients (13.0%), transverse myelitis in 15 patients (65.2%), and both in 5 patients (21.7%). All patients (100%) received pulse steroid therapy (intravenous methylprednisolone 1 g for 5 days) at the onset of the disease. Fifteen patients had plasma exchange therapy (65.2%). All patients received maintenance immunosuppressive treatment except 1 (4.3%).

CONCLUSION

NMOSD is a rare, broad-spectrum, polyphasic, rare disorder primarily affecting the optic pathway and the spinal cord either in isolation or simultaneously. Unfortunately, there are no adequate studies that assess NMOSD cohorts in Saudi Arabia despite the increased number of diagnosed cases. In addition, there is no registry for this disorder with only a few specialized centers dealing with its management. It is time to establish specialized demyelinating disease centers and build expertise in both common and rare diseases in this category.

Detection of Multiple Sclerosis Biomarkers in Serum by Ganglioside Microarrays and Surface Plasmon Resonance Imaging

Multiple sclerosis (MS) is an autoimmune disease that damages the myelin sheaths of nerve cells in the central nervous system. An individual suffering from MS produces increased levels of antibodies that target cell membrane components, such as phospholipids, gangliosides, and membrane proteins. Among them, anti-ganglioside antibodies are considered as important biomarkers to differentiate MS from other diseases that exhibit similar symptoms. We report here a label-free method for detecting a series of antibodies against gangliosides in serum by surface plasmon resonance imaging (SPRi) in combination with a carbohydrate microarray. The ganglioside array was fabricated with a plasmonically tuned, background-free biochip, and coated with a perfluorodecyltrichlorosilane (PFDTS) layer for antigen attachment as a self-assembled pseudo-myelin sheath. The chip was characterized with AFM and matrix-assisted laser desorption ionization mass spectrometry, demonstrating effective functionalization of the surface. SPRi measurements of patients' mimicking blood samples were conducted. A multiplexed detection of antibodies for anti-GT_1b, anti-GM₁, and anti-GA₁ in serum was demonstrated, with a working range of 1 to 100 ng/mL, suggesting that it is well suited for clinical assessment of antibody abnormality in MS patients. Statistical analyses, including PLS-DA and PCA show the array allows comprehensive characterization of cross reactivity patterns between the MS specific antibodies and can generate a wide range of information compared to traditional end point assays. This work uses PFDTS surface functionalization and enables direct MS biomarker detection in serum, offering a powerful alternative for MS assessment and potentially improved patient care.

Evaluating the Utility of Smartphone-Based Sensor Assessments in Persons With Multiple Sclerosis in the Real-World Using an App (elevateMS): Observational, Prospective Pilot Digital Health Study

Background

Multiple sclerosis (MS) is a chronic neurodegenerative disease. Current monitoring practices predominantly rely on brief and infrequent assessments, which may not be representative of the real-world patient experience. Smartphone technology provides an opportunity to assess people’s daily-lived experience of MS on a frequent, regular basis outside of episodic clinical evaluations.

Objective

The objectives of this study were to evaluate the feasibility and utility of capturing real-world MS-related health data remotely using a smartphone app, “elevateMS,” to investigate the associations between self-reported MS severity and sensor-based active functional tests measurements, and the impact of local weather conditions on disease burden.

Methods

This was a 12-week, observational, digital health study involving 3 cohorts: self-referred participants who reported an MS diagnosis, clinic-referred participants with neurologist-confirmed MS, and participants without MS (controls). Participants downloaded the elevateMS app and completed baseline assessments, including self-reported physical ability (Patient-Determined Disease Steps [PDDS]), as well as longitudinal assessments of quality of life (Quality of Life in Neurological Disorders [Neuro-QoL] Cognitive, Upper Extremity, and Lower Extremity Function) and daily health (MS symptoms, triggers, health, mobility, pain). Participants also completed functional tests (finger-tapping, walk and balance, voice-based Digit Symbol Substitution Test [DSST], and finger-to-nose) as an independent assessment of MS-related cognition and motor activity. Local weather data were collected each time participants completed an active task. Associations between self-reported baseline/longitudinal assessments, functional tests, and weather were evaluated using linear (for cross-sectional data) and mixed-effects (for longitudinal data) regression models.

Results

A total of 660 individuals enrolled in the study; 31 withdrew, 495 had MS (n=359 self-referred, n=136 clinic-referred), and 134 were controls. Participation was highest in clinic-referred versus self-referred participants (median retention: 25.5 vs 7.0 days). The top 5 most common MS symptoms, reported at least once by participants with MS, were fatigue (310/495, 62.6%), weakness (222/495, 44.8%), memory/attention issues (209/495, 42.2%), and difficulty walking (205/495, 41.4%), and the most common triggers were high ambient temperature (259/495, 52.3%), stress (250/495, 50.5%), and late bedtime (221/495, 44.6%). Baseline PDDS was significantly associated with functional test performance in participants with MS (mixed model–based estimate of most significant feature across functional tests [β]: finger-tapping: β=–43.64, P<.001; DSST: β=–5.47, P=.005; walk and balance: β=–.39, P=.001; finger-to-nose: β=.01, P=.01). Longitudinal Neuro-QoL scores were also significantly associated with functional tests (finger-tapping with Upper Extremity Function: β=.40, P<.001; walk and balance with Lower Extremity Function: β=–99.18, P=.02; DSST with Cognitive Function: β=1.60, P=.03). Finally, local temperature was significantly associated with participants’ test performance (finger-tapping: β=–.14, P<.001; DSST: β=–.06, P=.009; finger-to-nose: β=–53.88, P<.001).

Conclusions

The elevateMS study app captured the real-world experience of MS, characterized some MS symptoms, and assessed the impact of environmental factors on symptom severity. Our study provides further evidence that supports smartphone app use to monitor MS with both active assessments and patient-reported measures of disease burden. App-based tracking may provide unique and timely real-world data for clinicians and patients, resulting in improved disease insights and management.

Neurological misdiagnoses of lymphoma

BACKGROUND

Lymphoma of the nervous system is rare and usually involves the brain, spinal cord, or peripheral nerves. Hence, it has varied clinical presentations, and correct diagnosis is often challenging. Incorrect diagnosis delays the appropriate treatment and affects prognosis. We report 5 patients with delayed diagnosis of lymphoma involving the central and/or peripheral nervous system, initially evaluated for other neurological diagnoses. We also discuss the challenge of diagnosis and appropriate testing.

METHODS

Retrospective review of 2011-2019 records of patients with confirmed nervous system lymphoma diagnosed in a tertiary care medical center.

RESULTS

We present 5 adult patients initially evaluated for inflammatory myelopathy, inflammatory lumbosacral plexopathy, atypical parkinsonism, and demyelinating disease of the CNS. Final diagnosis of the nervous system lymphoma was delayed by 4 to 18 months and was based on tissue biopsy in 4, and on CSF and bone marrow examination in 1 patient.

CONCLUSIONS

Lymphoma may imitate various central and peripheral nervous system disorders. We suggest several red flags that indicate the need to consider lymphoma, including subacute but progressive symptomatic evolution, painful neurological deficit, unclear clinical diagnosis, and transient steroid responsiveness. Correct diagnosis often requires a combination of diagnostic tests, while pathology testing is crucial for early diagnosis and is strongly recommended in the appropriate clinical setting.

BOLD signal within and around white matter lesions distinguishes multiple sclerosis and non-specific white matter disease: a three-dimensional approach

Multiple sclerosis (MS) diagnostic criteria are based upon clinical presentation and presence of white matter hyperintensities on two-dimensional magnetic resonance imaging (MRI) views. Such criteria, however, are prone to false-positive interpretations due to the presence of similar MRI findings in non-specific white matter disease (NSWMD) states such as migraine and microvascular disease. The coexistence of age-related changes has also been recognized in MS patients, and this comorbidity further poses a diagnostic challenge. In this study, we investigated the physiologic profiles within and around MS and NSWMD lesions and their ability to distinguish the two disease states. MS and NSWMD lesions were identified using three-dimensional (3D) T₂-FLAIR images and segmented using geodesic active contouring. A dual-echo functional MRI sequence permitted near-simultaneous measurement of blood-oxygen-level-dependent signal (BOLD) and cerebral blood flow (CBF). BOLD and CBF were calculated within lesions and in 3D concentric layers surrounding each lesion. BOLD slope, an indicator of lesion metabolic capacity, was calculated as the change in BOLD from a lesion through its surrounding perimeters. We observed sequential BOLD signal reductions from the lesion towards the perimeters for MS, while no such decreases were observed for NSWMD lesions. BOLD slope was significantly lower in MS compared to NSWM lesions, suggesting decreased metabolic activity in MS lesions. Furthermore, BOLD signal within and around lesions significantly distinguished MS and NSWMD lesions. These results suggest that this technique shows promise for clinical utility in distinguishing NSWMD or MS disease states and identifying NSWMD lesions occurring in MS patients.

Can a diagnosis of multiple sclerosis be made without ruling out neuromyelitis optica spectrum disorder ?

BACKGROUND

The symptoms of multiple sclerosis (MS) can overlap with neuromyelitis optica spectrum disorder (NMOSD). Although testing is available for aquaporin 4 (AQP4) and myelin oligodendrocyte glycoprotein (MOG) antibodies, screening for NMOSD is recommended but not mandatory to establish a diagnosis of MS.

METHODS AND RESULTS

We queried 319,994 individuals who filed claims for MS and NMOSD in a Truven Health Analytics (THA) database and had at least one year of uninterrupted health insurance coverage. Of this cohort, 2001 (0.62%) were diagnosed as having NMOSD after an initial diagnosis of MS, based on ICD 9/10 codes. Since THA only offers claims-based data, we initiated an individual patient-based data search at our medical center to screen for potential misdiagnoses. We identified 4/54 (7.4%) NMOSD cases that were initially diagnosed as having MS.

CONCLUSIONS

The results from our small study have significant implications--symptoms, clinical presentation or classic radiological findings perhaps cannot reliably separate MS from NMOSD. If our study findings can be replicated, guidelines to diagnose MS ought to recommend that NMOSD be excluded first despite typical clinical and radiological findings pointing to MS.

The diagnostic value of IgG index versus oligoclonal bands in cerebrospinal fluid of patients with multiple sclerosis

Background

Diagnostic criteria for multiple sclerosis have been developed to guide the diagnostic process. In the latest revision of the McDonald criteria, the presence of oligoclonal bands may replace the need for dissemination in time. The aim of this study is to investigate if the less time-consuming analysis of immunoglobulin G index in cerebrospinal fluid can safely predict the findings of oligoclonal bands.

Methods

This is a retrospective study of patients with multiple sclerosis at three hospitals in South-East Norway where lumbar puncture is performed routinely. We included patients diagnosed with multiple sclerosis after 2005 with known oligoclonal band status and an immunoglobulin G index score.

Results

Of 1295 patients diagnosed during or after 2005, 93.8% were oligoclonal band positive at diagnosis. Of 842 multiple sclerosis patients with known immunoglobulin G index and oligoclonal band status, 93.3% were oligoclonal band positive and 76.7% had an elevated immunoglobulin G index. The positive predictive value of a high immunoglobulin G index when oligoclonal bands are positive was 99.4% (95% confidence interval 98.4–99.8%). The negative predictive value of a normal immunoglobulin G index when oligoclonal bands are negative was 26.5% (95% confidence interval 23.5–29.9%).

Conclusion

An immunoglobulin G index >0.7 has a positive predictive value >99% for oligoclonal bands. An elevated immunoglobulin G index adds diagnostic value versus oligoclonal bands and saves time in the diagnostic process.

Neuromyelitis optica spectrum disorders in the Arabian Gulf: challenges and growing experience

Neuromyelitis optica spectrum disorders (NMOSD) have been studied in different ethnic groups, including Asians, African-Americans, and Caucasians. Demonstrating the clinical features among diverse communities is important to understand the variable disease phenotypes, which will lead to further classification and better clinical management. Testing for antibody against aquaporin-4 (AQP4), the most common target antigen in NMOSD, is not available in many countries and tests use different methods, with variable sensitivity. With negative antibody results, the diagnosis of NMOSD becomes challenging and may affect the outcomes of patients with NMOSD. There are no adequate studies that assess NMOSD cohorts in the Arabian Gulf region, despite the increasing number of diagnosed cases. It is worth assessing NMOSD cohorts in the Arabian Gulf population to study the natural history of disease and to establish an epidemiological background for future perspectives. Various challenges to implement such a mission are outlined, including disease rarity, overlapping presenting symptoms and signs, which posed the issue of mimickers in the differential diagnosis, lack of specialized clinics, absence of highly sensitive testing methods for diagnosis, and the indefinite agreement on the negative AQP4 NMOSD criteria. Collaborative efforts started to take a place among many experts in the region to establish a registry of NMOSD patients for better perception of the disease pattern.

Toxocara infection in the differential diagnosis of multiple sclerosis in the Middle East

A critical step in the diagnosis of multiple sclerosis is to rule out a heterogeneous variety of multiple sclerosis mimickers, which is crucial in the era of powerful immune-modulator treatments. In this review, we discuss the background of toxocariasis in general, present central nervous system Toxocara infection as one of the multiple sclerosis mimickers in the Middle East, and share our experience about the diagnosis and management of this condition. This entity seems very relevant in a region such as the Middle East, where displacement of populations and conflict can result in non-hygienic food and water management bundles. The diagnosis should be entertained, especially when assessing patients with myelopathy. The presence of a single lesion in the spinal cord with inflammatory features should prompt serological testing for Toxocara IgG and IgM in serum and the cerebrospinal fluid. This infection is treatable, with the regimen of high-dose albendazole being one of the most accepted treatments. Although most cases exhibit a good prognosis, some have residual deficits localized to the affected spinal cord level.

Diagnosis, Differential Diagnosis, and Misdiagnosis of Multiple Sclerosis

PURPOSE OF REVIEW

The diagnosis of multiple sclerosis (MS) is often challenging. This article discusses approaches to the clinical assessment for MS that may improve diagnostic accuracy.

RECENT FINDINGS

Contemporary diagnostic criteria for MS continue to evolve, while knowledge about diseases that form the differential diagnosis of MS continues to expand. Recent data concerning causes of MS misdiagnosis (the incorrect assignment of a diagnosis of MS) have further informed approaches to syndromes that may mimic MS and the accurate diagnosis of MS.

SUMMARY

This article provides a practical update on MS diagnosis through a discussion of recently revised MS diagnostic criteria, a renewed consideration of MS differential diagnosis, and contemporary data concerning MS misdiagnosis.

Estimating the prevalence of multiple sclerosis using 56.6 million electronic health records from the United States

Background/objective:

In 2019, the 2010 U.S. multiple sclerosis (MS) prevalence was robustly estimated (265.1–309.2/100,000) based on large administrative health-claims datasets. Using 56.6 million electronic health records (EHRs), we sought to generate complementary age, sex, and race standardized estimates.

Methods/results:

Using de-identified EHRs and 2018 U.S. Census data, we estimated an age- and sex-standardized MS prevalence of 219.5/100,000 which increased to 274.5/100,000 when accounting for White and Black race alone. Women aged 50 to 69 years had the highest prevalence (>600/100,000). Among White and Black Americans, the age- and sex-standardized prevalence was 283.7 and 226.1 per 100,000, respectively.

Conclusion:

Using 56.6 million EHRs and standardizing for age, sex, and race (White and Black Americans only), we estimated at least 810,504 Americans were living with MS in 2018.

Serum-based differentiation between multiple sclerosis and amyotrophic lateral sclerosis by Random Forest classification of FTIR spectra

The challenging diagnosis and differentiation between multiple sclerosis and amyotrophic lateral sclerosis relies on the clinical assessment of the symptoms along with magnetic resonance imaging and sampling cerebrospinal fluid for the search of biomarkers for either disease. Despite the progress made in imaging techniques and biomarker identification, misdiagnosis still occurs. Here we used 2.5 μL of serum samples to obtain the infrared spectroscopic signatures of sera of multiple sclerosis and amyotrophic lateral sclerosis patients and compared them to those of healthy controls. The spectra are then classified with the help of a two-fold Random Forest cross-validation algorithm. This approach shows that infrared spectroscopy is powerful in discriminating between the two diseases and healthy controls by offering high specificity for multiple sclerosis (100%) and amyotrophic lateral sclerosis (98%). In addition, data after six and twelve months of treatment of the multiple sclerosis patients with biotin are discussed.

Predictors of amyotrophic lateral sclerosis mimic syndrome

The term amyotrophic lateral sclerosis mimic syndrome (ALSms) includes pathologies that present signs or symptoms similar to those caused by amyotrophic lateral sclerosis (ALS), which can lead to misdiagnosis. In general, any kind of misdiagnosis can result in negative clinical, psychological and economic consequences as well diagnostic and treatment delay. The objectives were to determine the frequency and to compare the demographic and clinical characteristics of patients with ALS and ALSms in our ALS clinic. We retrospectively studied all patients evaluated from 2007 to 2017 including only patients with a definite final diagnosis. Out of 368 patients with motor neuron disease symptomatology, 43 (11.7%) had an ALSms. The most frequent etiology was compressive myelopathy (32.6%). Multivariate analysis considering positive associations was statistically significant for patients having only upper or lower motor neuron signs in the physical examination, a non-compatible electromyogram (EMG), as well as atypical first symptoms. ALS misdiagnosis is an ongoing and not infrequent problem. From our series of patients, atypical symptoms, absence of EMG pathological findings or isolated upper or lower motor neuron disease should prompt suspicion of a differential diagnosis.

The misdiagnosis of functional disorders as other neurological conditions

BACKGROUND

Several studies have shown that when patients with functional neurological disorders are followed up, it is rare to find another neurological condition that better explains the initial symptoms in hindsight. No study has examined the reverse, studying patients with a range of neurological disease diagnoses with the aim of assessing how often a new diagnosis of functional disorder better explains the original symptoms.

METHODS

A prospective multi-centre cohort study of 2637 new neurology outpatient referrals from primary care in Scotland. Neurologists provided initial diagnoses and a rating of the extent to which their symptoms were explained by an 'organic' neurological disease. Patients were followed up 19 months later with a questionnaire to their primary care physician asking about diagnostic change, and when indicated also by discussion with the original assessing neurologist and review of secondary care records.

RESULTS

Valid responses were obtained for 2378 out of 2637 patients (90%) with symptoms 'largely' or 'completely' explained by organic disease at baseline. At follow-up, we found diagnostic errors in 48 patients. Of those, ten (0.4%) had a functional diagnosis and 38 patients (1.6%) had a different 'organic' diagnosis which better explained the original symptoms.

CONCLUSIONS

Patients diagnosed with neurological disease sometimes have a functional diagnosis at follow-up which, with hindsight, better explains the original symptoms. This occurs at a frequency similar to the misdiagnosis of 'organic' neurological disease as functional disorder. Misdiagnosis can harm patients in either direction, especially as we enter an era of evidence-based treatment for functional neurological disorders.

Clinical trials in multiple sclerosis: potential future trial designs

Clinical trials of new treatments in multiple sclerosis (MS) currently require large sample sizes and long durations in order to yield reliable results. The differential responses of an already heterogeneous population of MS patients to individual disease-modifying therapies (DMTs) will further complicate future trials. MS trials with smaller samples and faster outcomes are conceivable through the substitution of current clinical and MRI outcomes with objectively measureable genomic and proteomic biomarkers. Currently, biomarkers that could be utilized for diagnosis and monitoring of MS disease activity are in the early validation phase. The power of single biomarkers or multiple correlated biomarkers to predict prognosis and response to treatment could initially be compared with currently accepted methods. These prospectively validated disease biomarkers could then be used to subcategorize the spectrum of MS patients into a finite number of endophenotypes with demonstrable different molecular pathogeneses and DMT response profiles. Newly developed DMT could potentially be assessed within specific endophenotypes and compared with pharmacogenomically relevant active comparator DMT. This approach may increase the efficiency of MS trials through homogenization of patient population and minimization of nonresponders in study groups, providing the potential for the development of targeted therapies.

Familial multiple sclerosis patients have a shorter delay in diagnosis than sporadic cases

BACKGROUND

The diagnosis of multiple sclerosis (MS) is still complicated despite improvement in diagnostic guidelines. This means that time from first symptom to diagnosis in some cases is prolonged. Many aspects of MS aetiology are unknown, but the involvement of a genetic component is well established. This is also highlighted by the occurrence of familial MS cases, which represent 10-20% of all MS cases. We hypothesize that subsequent family members in a MS family, have a shorter time from onset of disease to diagnosis compared to sporadic MS cases. To investigate this, we have conducted a register study comparing time from onset to diagnosis in familial and sporadic MS cases.

METHODS

This is a nationwide register study based on information from the Danish Multiple Sclerosis Registry and the Danish Civil Registration System. We included familial (first-degree relatives) and sporadic MS cases and calculated time lag between onset and diagnosis of MS for sporadic MS cases and for1st, 2nd and 3rd family members within the MS families. Median test and Cox regression were the statistical methods used to compare the familial and sporadic groups.

RESULTS

We found that 2nd and 3rd affected family member had a significant shorter time from first symptom to diagnosis compared to sporadic MS cases (2nd family member: Hazard Ratio (HR): 1.12, CI: 1.03-1.21, p = 0.007 adjusted: HR: 0.95 p = 0.22, CI 0.89-1-03 and 3rd family member HR: 1.64 CI: 1.22-2.20, p = 0.001 adjusted model: HR: 1.70, p-value: 0.000, CI: 1.32-2.18). The same difference was not seen between 1st family members and sporadic cases (HR: 1.05, CI: 0.98-1.13, p = 0.15, adjusted: 0.98, p-value: 0.53, CI: 0.91-1.05). Estimated marginal mean delay in the four groups were 4.60 years (95% CI: 4.11-5.01) in1st family members, 4.23 years (3.71-4.75) in 2nd family members, 2.11 years (0.95-3.26) in 3rd family members and 4.99 years (4.99-4.99) in sporadic MS cases.

CONCLUSION

The 2nd and 3rd family members in MS families tend do get diagnosed faster than sporadic cases. This has implications in the diagnostic process of familial MS cases.

Illuminating an Invisible Epidemic: A Systemic Review of the Clinical and Economic Benefits of Early Diagnosis and Treatment in Inflammatory Disease and Related Syndromes

Healthcare expenditures in the United States are growing at an alarming level with the Centers for Medicare and Medicaid Services (CMS) projecting that they will reach $5.7 trillion per year by 2026. Inflammatory diseases and related syndromes are growing in prevalence among Western societies. This growing population that affects close to 60 million people in the U.S. places a significant burden on the healthcare system. Characterized by relatively slow development, these diseases and syndromes prove challenging to diagnose, leading to delayed treatment against the backdrop of inevitable disability progression. Patients require healthcare attention but are initially hidden from clinician's view by the seemingly generalized, non-specific symptoms. It is imperative to identify and manage these underlying conditions to slow disease progression and reduce the likelihood that costly comorbidities will develop. Enhanced diagnostic criteria coupled with additional technological innovation to identify inflammatory conditions earlier is necessary and in the best interest of all healthcare stakeholders. The current total cost to the U.S. healthcare system is at least $90B dollars annually. Through unique analysis of financial cost drivers, this review identifies opportunities to improve clinical outcomes and help control these disease-related costs by 20% or more.

Prevalence of asthma in multiple sclerosis: A United States population-based study

BACKGROUND

Multiple sclerosis (MS) and asthma are complex multifactorial diseases which adversely impact daily functioning. However, the prevalence of asthma in those with MS is not clear. The objective of this study is to characterize the prevalence of asthma in those with MS, with considerations for age, gender, and race.

METHODS

We conducted a U.S. population-based, cross-sectional study of electronic health record information for 56.6 million Americans available in the IBM® Explorys EPM: Explore database. We evaluated the prevalence of asthma in MS (N = 141,880) and non-MS (N = 56,416,790) cohorts, stratifying by age, gender, and race (All, White Americans, and African Americans).

RESULTS

The prevalence of asthma was significantly greater among those with MS than the general population across age, gender, and racial subpopulations. Adjusting for age and gender, asthma was three times more common in MS. In the MS cohort, the prevalence of asthma had a U-shaped distribution with respect to age, with the greatest asthma prevalence among the young and the elderly (> 20% prevalence among those <30 or ≥80 years; prevalence range: 15 to 30%); this significantly differed from the fairly uniform distribution observed in the non-MS cohort (prevalence range: 4 to 9%). These patterns were relatively consistent when stratifying by gender and race.

CONCLUSION

Asthma is significantly more common in those with MS than in the general population - particularly in the young and elderly - irrespective of gender and race. The results add to the growing MS comorbidity literature, and emphasizes the need for comorbidity management as a part of comprehensive MS patient care.

Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disorders: Toward a New Spectrum of Inflammatory Demyelinating CNS Disorders?

Inflammatory demyelinating CNS syndromes include, besides their most common entity multiple sclerosis (MS), several different diseases of either monophasic or recurrent character—including neuromyelitis optica spectrum disorders (NMOSDs) and acute disseminated encephalomyelitis (ADEM). Early diagnostic differentiation is crucial for devising individual treatment strategies. However, due to overlapping clinical and paraclinical features diagnosis at the first demyelinating event is not always possible. A multiplicity of potential biological markers that could discriminate the different diseases was studied. As the use of autoantibodies in patient management of other autoimmune diseases, is well-established and evidence for the critical involvement of B cells/antibodies in disease pathogenesis in inflammatory demyelinating CNS syndromes increases, antibodies seem to be valuable diagnostic tools. Since the detection of antibodies against aquaporin-4 (AQP-4), the understanding of immunopathogenesis and diagnostic management of NMOSDs has dramatically changed. However, for most inflammatory demyelinating CNS syndromes, a potential antigen target is still not known. A further extensively studied possible target structure is myelin oligodendrocyte glycoprotein (MOG), found at the outermost surface of myelin sheaths and oligodendrocyte membranes. With detection methods using cell-based assays with full-length, conformationally correct MOG, antibodies have been described in early studies with a subgroup of patients with ADEM. Recently, a humoral immune reaction against MOG has been found not only in monophasic diseases, but also in recurrent non-MS diseases, particularly in pediatric patients. This review presents the findings regarding MOG antibodies as potential biological markers in discriminating between these different demyelinating CNS diseases, and discusses recent developments, clinical implementations, and data on immunopathogenesis of MOG antibody-associated disorders.

An 'epidemic' of multiple sclerosis and falling infection rates? Reflecting on comparisons made and the rising multiple sclerosis incidence in Bach's 2002 New England Journal of Medicine figure

BACKGROUND AND PURPOSE

We set out to revisit and comment on the evidence surrounding a popular figure published in the New England Journal of Medicine (2002), which suggests that the incidence of immune-mediated diseases, including multiple sclerosis (MS), is increased by reduced exposure to infections.

METHODS

Commentary.

RESULTS

We found that, to date (May 2017), this influential article has been cited >2000 times. However, on close investigation of the figure, we noticed some problems. Specifically, we observed several challenges inherent in using ecological data from disparate studies and countries to make conclusions surrounding the temporal patterns and relationships between diseases. For example, the figure depicts incidence data for MS based solely on a limited group of individuals with MS (n = 637; 455 women and 182 men) living within the region of Sassari on the island of Sardinia, known for its unique genealogy and risk of MS. However, the infectious-related data were based primarily on large population studies from the USA, with one derived from army recruits in France.

CONCLUSIONS

We encourage the scientific community to apply rigorous, consistent methods in order to confirm or refute whether a strong, direct relationship does or does not exist between the incidence of MS and infectious diseases. Further, our article highlights a major knowledge gap that would benefit from a thorough review of the temporal trends related to MS incidence. Collation of this wide body of knowledge may provide a balanced understanding of this important topic and would best serve the progress of MS research.

Misdiagnosis of multiple sclerosis: Impact of the 2017 McDonald criteria on clinical practice

Misdiagnosis of multiple sclerosis (MS) (the incorrect assignment of a diagnosis of MS) remains a problem in contemporary clinical practice. Studies indicate that misdiagnosed patients are often exposed to prolonged unnecessary health care risks and morbidity. The recently published 2017 revision of the McDonald criteria for the diagnosis of MS provides an opportunity to consider the effect of these revisions on the problem of MS misdiagnosis. The 2017 McDonald criteria include several new recommendations to reduce potential for misdiagnoses. The criteria should be used for the types of patients in which validation studies were performed, specifically those patients who present with typical demyelinating syndromes. MRI lesion characteristics were defined for which McDonald criteria would be expected to perform with accuracy. However, 2017 revisions, which now include assessment for cortical lesions, and the inclusion of symptomatic lesions and positive oligoclonal bands for the fulfillment of diagnostic criteria, may have the potential to lead to misdiagnosis of MS if not applied appropriately. While the 2017 McDonald criteria integrate issues relating to MS misdiagnosis and incorporate specific recommendations for its prevention more prominently than prior criteria, the interpretation of clinical and radiologic assessments upon which these criteria depend will continue to allow misdiagnoses. In patients with atypical clinical presentations, the revised McDonald criteria may not be readily applied. In those situations, further evaluation or monitoring rather than immediate diagnosis of MS is prudent.

The Role of Prescribing Generic (Non-proprietary) Drugs in the Prevalence of Therapeutic Inertia in Multiple Sclerosis Care

Importance: The prescription of generic (non-proprietary) compared to brand-name drugs is increasing worldwide. In many developing and emerging countries, generics companies market products at similar costs as brand-name competitors benefiting from more flexible compliance rules and regulations for marketing their products in the health system. Together, this phenomenon may influence prescriber's behavior (e.g., maintaining the same treatment despite guideline's recommendations or despite evidence of disease progression).

Objectives: To compare the prevalence of therapeutic inertia (TI) between primary prescription of brand-name vs. generic drugs in the management of MS in Argentina.

Design: We conducted a population-based online study comprising 117 neurologists with expertise in MS. Participants answered questions regarding their clinical practice, most commonly prescribed disease modifying agents, and therapeutic choices of 10 simulated case-scenarios that assessed TI. Inertia was defined as the lack of treatment initiation or escalation despite evidence of clinical and radiological activity (8 case-scenarios, 720 individual responses). We created the generic-brand name score (GBS) according to the 5 most frequently prescribed generic (n = 16) vs. brand-name (n = 9) drugs for MS, where scores higher than 1 indicated higher prescription of generic drugs and scores lower than 1 indicated higher prescription of brand-name agents. Candidate predictors of prescribing generic drugs included demographic data, MS specialist vs. general neurologist, practice setting, years of practice, volume of MS patients, risk preferences, costs of annual treatment.

Participants and setting: population-based prospective study using including neurologists who care for patients with multiple sclerosis across Argentina.

Exposure: prescription of generic vs. brand-name MS drugs

Main outcome of interest: Therapeutic inertia (TI), defined as lack of treatment escalation when goals are unmet. Secondary outcomes included factors associated with generic drug prescription and costs of MS treatment.

Results: Ninety participants completed the study (completion rate 76.9%). TI was observed in 153 (21.3%) of participants' responses. The evaluation of aggregate responses revealed a mean GBS score (SD) of 3.44 (2.1), with 46 (51.1%) participants having a GBS equal to or higher than 1. Older age (OR 1.19; 95% CI 1.00–1.42), being a general neurologist (OR 3.91; 95% CI 1.19–12.8), and being more willing to take risks in multiple domains (SOEP score OR 1.06, 95% CI 1.01–1.12) were associated with higher prescription of generic drugs in MS care. Costs of treatment were not associated with prescribing generic drugs. There was no difference in the annual costs of MS treatment for primary prescribers of brand-name vs. generic drugs (67,500 US$ vs. 67,496 US$; p = 0.99).

The evaluation of individual responses revealed that participants with higher prescription of generics—reflected by a higher GBS—had higher incident risk of TI (mean GBS 3.61 for TI vs. 2.96 for no TI; p < 0.001). Multivariate analysis revealed that a prescription of generic agents was associated with an increased incident risk of TI (OR 1.56; 95%CI 1.07–2.29). There was no difference in the annual costs of MS treatment for participants that exhibited TI vs. those without TI (67,426 US$ vs. 67,704 US$; p = 0.66).

Conclusions: General neurologist, older age, and willingness to take risks were associated with increased prescription of generic drugs despite similar costs compared to brand-name agents. In our study, the prescription of generic-MS drugs was associated with a higher incident risk of therapeutic inertia.

The neuropsychiatry of multiple sclerosis

Multiple sclerosis (MS), an immune-mediated demyelinating condition, is the most common neurological disease affecting young adults in the UK. It has a high psychiatric comorbidity and over half of patients have some degree of cognitive impairment that adds to the burden of disability. This article reviews the psychiatric and cognitive manifestations of MS and their detection and treatment. Recent advances in the treatment of the disease are briefly reviewed and the impact of disease-modifying therapies on psychiatric morbidity and cognitive impairment is discussed.

LEARNING OBJECTIVES

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DECLARATION OF INTEREST

None.

Fabry disease and multiple sclerosis misdiagnosis: the role of family history and neurological signs

Fabry disease (FD) is an X-linked inherited lysosomal storage disorder caused by α galactosidase A (α-gal A) deficiency. Central nervous system involvement and chronic white matter lesions are observed in both FD and multiple sclerosis (MS), which can confound the differential diagnosis. We analyzed the GLA gene, which encodes α-gal A, in 86 patients with clinical and neuroradiological findings consistent with MS to determine whether they had FD. We identified four women initially diagnosed with MS who had GLA mutations associated with FD. Our results indicate that family history besides neurological findings should be evaluated in patients with an uncertain diagnosis of MS. Also the involvement of organs outside the central nervous system can support the FD diagnosis.