Secondary progressive multiple sclerosis: A national consensus paper on diagnostic criteria

BACKGROUND

In clinical practice, the diagnosis of secondary progressive multiple sclerosis (SPMS) is often delayed, retrospective and non-reproducible, as there are no consensus criteria that define the advent of SPMS. Early identification of SPMS is essential to improve patient care.

METHODS

Eight regional board meetings in France involving 56 multiple sclerosis (MS) experts (neurologists) were convened to discuss diagnostic criteria for SPMS. Subsequently, a national board meeting of 13 neurologists (with an expert representing each geographical region) was held to review points of convergence or divergence between regions and to develop a national consensus document.

RESULTS

Based on the discussions from the regional boards, the MS experts at the national board retained the worsening of the EDSS score, with compatible clinical features, as the only consensus criterion for the diagnosis of SPMS in clinical practice. The patient should have experienced during at least the previous 6 months and in the absence of any relapse, a worsening in the EDSS score of +1.0 point (if the previous EDSS was≤5.0) or of +0.5 point (if the previous EDSS was≥5.5), with a pyramidal or cerebellar functional system score≥2 and without setting a minimum EDSS score; or, in case of a stable EDSS score≥4.0, a worsening of a functional score. This worsening should be confirmed within 3 to 6 months. According to the MS experts, the patient's age, duration of illness and a minimal threshold EDSS score are only risk factors for transition to SPMS. Patient reports during consultation and cognitive impairment are important warning signs, which should trigger an objective assessment with specific tests or closer monitoring. Clinical relapse and/or MRI activities are non-discriminatory for making the diagnosis of SPMS.

CONCLUSIONS

The experts defined precise diagnostic criteria adapted to clinical practice for earlier identification of SPMS, paving the way for better management of this stage of the disease.

Clinical failure of natalizumab in multiple sclerosis: Specific causes and strategy

BACKGROUND

Natalizumab is a very effective treatment of multiple sclerosis (MS). Failure is rare and should lead to consider some specific etiologies. The purpose of our study was to describe causes of subacute neurological events under natalizumab.

METHODS

Observational single-center retrospective study in the MS expert center of Lyon, France.

INCLUSION CRITERIA

any patient with definite MS who received at least three infusions of natalizumab between April 2007 and February 2017. Clinical data were extracted from the Lyon EDMUS/OFSEP database. Events of interest: occurrence of a subacute neurological deficit, characterized by new clinical symptoms. We excluded pseudo-relapses and progression.

FINDINGS

A subacute neurological deficit occurred in 35 cases, for 607 patients treated with natalizumab. Ten patients presented natalizumab antibodies, nine had progressive multifocal leukoencephalopathy (PML), five presented an isolated subacute neurological deficit and two had AQP4 antibodies. No myelin oligodendrocyte glycoprotein (MOG) antibodies were found.

INTERPRETATION

The occurrence of an acute or subacute neurological deficit with natalizumab is rarely a MS relapse and should lead systematically to explore some important alternate etiologies, eliminating PML first.

MRI characteristics of MOG-Ab associated disease in adults: An update

Our knowledge of the radiological spectrum of myelin oligodendrocyte glycoprotein antibody associated disease (MOGAD) is growing rapidly. An update on the radiological features of the disease, and its evolution is thus necessary. Magnetic resonance imaging (MRI) has an increasingly important role in the differential diagnosis of MOGAD particularly from aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder (AQP4-NMOSD), and multiple sclerosis (MS). Differentiating these conditions is of prime importance because the management is different between the three inflammatory diseases, and thus could prevent further attack-related disability. Therefore, identifying the MRI features suggestive of MOGAD has diagnostic and prognostic implications. We herein review optic nerve, spinal cord and the brain MRI findings from MOGAD adult patients, and compare them to AQP4-NMOSD and MS.

Neuraxial analgesia is not associated with an increased risk of post-partum relapses in MS

Background:

Obstetrical analgesia remains a matter of controversy because of the fear of neurotoxicity of local anesthetics on demyelinated fibers or their potential relationship with subsequent relapses.

Objective:

To assess the impact of neuraxial analgesia on the risk of relapse during the first 3 months post-partum, with a focus on women who experienced relapses during pregnancy.

Methods:

We analyzed data of women followed-up prospectively during their pregnancies and at least 3 months post-partum, collected in the Pregnancy in Multiple Sclerosis (PRIMS) and Prevention of Post-Partum Relapses with Progestin and Estradiol in Multiple Sclerosis (POPARTMUS) studies between 1992–1995 and 2005–2012, respectively. The association of neuraxial analgesia with the occurrence of a post-partum relapse was estimated by logistic regression analysis.

Results:

A total of 389 women were included, 215 from PRIMS and 174 from POPARTMUS. In total, 156 women (40%) had neuraxial analgesia. Overall, 24% experienced a relapse during pregnancy and 25% in the 3 months post-partum. Women with a pregnancy relapse were more likely to have a post-partum relapse (odds ratio (OR) = 1.83, p = 0.02), independently of the use of neuraxial analgesia. There was no association between neuraxial analgesia and post-partum relapse (OR = 1.08, p = 0.78).

Conclusion:

Neuraxial analgesia was not associated with an increased risk of post-partum relapses, whatever multiple sclerosis (MS) activity during pregnancy.

Reliability of longitudinal brain volume loss measurements between 2 sites in patients with multiple sclerosis: comparison of 7 quantification techniques

BACKGROUND AND PURPOSE

Brain volume loss is currently a MR imaging marker of neurodegeneration in MS. Available quantification algorithms perform either direct (segmentation-based techniques) or indirect (registration-based techniques) measurements. Because there is no reference standard technique, the assessment of their accuracy and reliability remains a difficult goal. Therefore, the purpose of this work was to assess the robustness of 7 different postprocessing algorithms applied to images acquired from different MR imaging systems.

MATERIALS AND METHODS

Nine patients with MS were followed longitudinally over 1 year (3 time points) on two 1.5T MR imaging systems. Brain volume change measures were assessed using 7 segmentation algorithms: a segmentation-classification algorithm, FreeSurfer, BBSI, KN-BSI, SIENA, SIENAX, and JI algorithm.

RESULTS

Intersite variability showed that segmentation-based techniques and SIENAX provided large and heterogeneous values of brain volume changes. A Bland-Altman analysis showed a mean difference of 1.8%, 0.07%, and 0.79% between the 2 sites, and a wide length agreement interval of 11.66%, 7.92%, and 11.94% for the segmentation-classification algorithm, FreeSurfer, and SIENAX, respectively. In contrast, registration-based algorithms showed better reproducibility, with a low mean difference of 0.45% for BBSI, KN-BSI and JI, and a mean length agreement interval of 1.55%. If SIENA obtained a lower mean difference of 0.12%, its agreement interval of 3.29% was wider.

CONCLUSIONS

If brain atrophy estimation remains an open issue, future investigations of the accuracy and reliability of the brain volume quantification algorithms are needed to measure the slow and small brain volume changes occurring in MS.

Diffusion tensor-MRI evidence for extra-axonal neuronal degeneration in caudate and thalamic nuclei of patients with multiple sclerosis

BACKGROUND AND PURPOSE

MS is an inflammatory demyelinating disease affecting both WM and GM. While WM lesions are easily visualized by conventional MR imaging, the detection of GM alterations remains challenging. This diffusion tensor MR imaging study aimed to detect and characterize diffuse microscopic alterations in 2 deep GM structures, the caudate nucleus and the thalamus, in patients with RR and SP MS. The relationship between diffusivity markers, and atrophy of the caudate and the thalamus, as well as brain lesion load and clinical status of the patients was also explored.

MATERIALS AND METHODS

Twenty-three RR and 18 SP patients, along with 27 healthy controls, underwent MR imaging examination including anatomic and DTI acquisitions. Volumes, mean FA, and MD of the caudate and the thalamus, as well as WM lesion volumes, were assessed.

RESULTS

FA was significantly (P < .001) increased in the caudate and the thalamus of patients with MS compared with controls, and was higher in SP compared with RR patients. Increased FA was associated with volume decreases of caudate (r = -0.712; P < .001) and thalamus (r = -0.407; P < .01) in patients with MS. WM T2 lesion load was significantly associated with caudate (r = 0.611; P < .001) and thalamic (r = 0.354; P < .05) FA. Caudate FA, and, to a lesser extent, thalamic FA, were associated with functional deficits, as measured by EDSS and MSFC.

CONCLUSIONS

Increased FA in the caudate and the thalamus may constitute a sensitive marker of MS pathologic processes, such as loss of dendrites and/or swelling of neuronal cell bodies.

Primary angiitis of the central nervous system: response to mycophenolate mofetil

Primary angiitis of the central nervous system (PACNS) is a rare inflammatory disease restricted to the CNS of unknown cause. Clinical presentation and evolution are highly variable with potentially fluctuating signs and symptoms. Brain imaging often shows supratentorial ischaemic lesions. Definite diagnosis is established by brain biopsy. Treatment usually combines glucocorticosteroids and cyclophosphamide. A case of PACNS is reported here, which was proved by a brain biopsy and characterised by unusually prominent involvement of the posterior cerebral fossa. Successful treatment with mycophenolate mofetil in combination with steroids is described.

[Correlation between cranial vault size and brain size over time: preliminary MRI evaluation]

OBJECTIVES

To correlate changes of cranial vault measurements of an adult population during the aging process with brain size using the maximum width of the third ventricle in the axial AC-PC plane.

MATERIALS AND METHODS

Prospective study of 126 adult subjects (range: 20 to 80 years) with normal brain MRI and without history of neuropsychiatric disorder. MEASUREMENTS INCLUDED: Cranial vault (Maximum length: Glabella-Opisthocranion, Maximum width: euryon-euryon, and maximum height: Basion-Vertex) measurements and maximum width of the third ventricle in the A C-PC plane.

RESULTS

Vault measurements (length, width, high) were similar for every age group, irrespective of gender. The variability of cranial vault measurements between individuals was low (<1 cm). Cranial vault measurements were larger for men, but this was not significant when adjusted for body height Comparatively, a gradual widening of the third ventricle, with an exponential behavior, was observed with advancing age.

CONCLUSION

Our results indicate that cranial vault measurements are stable over time (between 20-80 years) comparatively to brain atrophy with advancing age. The low variability of cranial vault measurements and their stability over time should be taken into account during segmentation and normalization of brain parenchymal structures.

[Polymorphism of epilepsy associated with the A3243G mutation of mitochondrial DNA (MELAS): reasons for delayed diagnosis]

INTRODUCTION

Mitochondrial disease is a potential diagnosis in patients with epilepsy beginning in childhood or adolescence with a typical polymorphic presentation and preponderant occipital lobe seizures. Diagnosis may however be delayed in some patients with long-standing disease, particularly when cardinal mitochondrial symptoms are missing; clinical manifestations may be dissociated over time leading to genetic diagnostic tests being prescribed long after disease onset.

OBSERVATION

We report the case of a 17 year old woman in whom the diagnosis of lipothymic episodes, migraine, idiopathic photo-sensitive generalized epilepsy, and partial occipital epilepsy complicated by occipital epileptic status were successively proposed because of the initial clinical presentation and the slow disease course. Eleven years after disease onset the diagnosis of progressive myoclonic epilepsy was made due to the occurrence of myoclonic jerks with giant SEPs associated with a cerebellar syndrome, deterioration of psychomotor performances and diffuse slowing of EEG activity with pseudo-periodic bursts of delta waves. Genetic analysis showed an A3243G mutation of mitochondrial DNA, usually correlated with the MELAS phenotype, while the clinical presentation of progressive myoclonic epilepsy was more suggestive of MERRF.

CONCLUSION

Although each of the symptoms successively observed in this patient has been reported in MELAS, the slow course of the disease, which is unusual in this mutation, the absence of stroke-like episodes, and the polymorphism of the epilepsy all contributed to delayed final diagnosis.