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.

Immunosuppressive therapy is more effective than interferon in neuromyelitis optica

To determine long-term treatment (LTT) of neuromyelitis optica (NMO), we retrospectively reviewed therapies of 26 patients with NMO followed in five French neurological departments. To assess LTT efficacy, the probability of relapse free after LTT was analysed. Patients were divided into two groups according to the first treatment receiving interferon beta (IFN Group, seven patients) or immunosuppressants (IS Group, 19 patients). The probability of relapse was significantly lower in the IS Group (P = 0.0007). From our results, interferon beta is not recommended, and one of the best current therapeutic options for NMO appears to be immunosuppressants. Multiple Sclerosis 2007; 13: 256–259. http://msj.sagepub.com

Leukoencephalopathies associated with inborn errors of metabolism in adults

The discovery of a leukoencephalopathy is a frequent situation in neurological practice and the diagnostic approach is often difficult given the numerous possible aetiologies, which include multiple acquired causes and genetic diseases including inborn errors of metabolism (IEMs). It is now clear that IEMs can have their clinical onset from early infancy until late adulthood. These diseases are particularly important to recognize because specific treatments often exist. In this review, illustrated by personal observations, we give an overview of late-onset leukoencephalopathies caused by IEMs.

[Treatable hereditary neuro-metabolic diseases]

Hereditary metabolic diseases may appear during adolescence or young adulthood, revealed by an apparently unexplained neurological or psychiatric disorder. Certain metabolic diseases respond to specific treatments and should be identified early, particularly in emergency situations where rapid introduction of a treatment can avoid fatal outcome or irreversible neurological damage. The main diseases leading to an acute neurological syndrome in the adult are urea cycle disorders, homocysteine metabolisms disorders and porphyria. More rarely, Wilson's disease, aminoacid diseases, organic aciduria, or pyruvate dehydrogenase deficiency, beta-oxidation disordes or biotin metabolism may be involved. Most emergency situations can be screen correctly with simple tests (serum ammonia, homocysteine, lactate, urinary prophyrines, acylcarnitine pattern, amino acid and organic acid chromatography). For chronic situations, the main treatable diseases are Wilson's disease, homocysteine, cerebrotendinous xanthomatosis, Refsum's disease, vitamin E deficiency, Gaucher's disease, Fabry's disease, and neurotransmitter metabolism disorders. We present treatable metabolic disorders as a function of the different clinical situations observed in adults.

Hereditary spastic paraparesis in adults associated with inborn errors of metabolism: a diagnostic approach

Spastic paraparesis is a general term describing progressive stiffness and weakness in the lower limbs caused by pyramidal tract lesions. This clinical situation is frequently encountered in adult neurology. The diagnostic survey is usually limited to searching for acquired causes (spinal cord compression, inflammatory, metabolic, infectious diseases) and the so-called 'hereditary spastic paraparesis'. Although poorly recognized by neurologists, spastic paraparesis is also one of the multiple presentations of inborn errors of metabolism (IEMs) in children and adults. Pyramidal signs are usually included in a diffuse neurological or systemic clinical picture; however, in some cases spastic paraparesis remains the only symptom for years. Since these metabolic causes are often treatable, it is essential to include them in the general diagnostic approach to spastic paraparesis. Here we review IEMs causing paraparesis in adults.

Epilepsy and inborn errors of metabolism in adults: a diagnostic approach

Inborn errors of metabolism (IEMs) represent poorly known causes of epilepsy in adulthood. Although rare, these are important to recognize for several reasons: some IEMs respond to specific treatments, some antiepileptic drugs interfering with metabolic pathways may worsen the clinical condition, and specific genetic counselling can be provided. We review IEMs potentially revealed by epilepsy that can be encountered in an adult neurology department. We distinguished progressive myoclonic epilepsies (observed in some lysosomal storage diseases, respiratory chain disorders and Lafora disease), from other forms of epilepsies (observed in disorders of intermediary metabolism, including porphyrias, creatine metabolism defects, glucose transporter (GLUT-1) deficiency, Wilson disease or succinic semialdehyde dehydrogenase deficiency). We propose a diagnostic approach and point out clinical, radiological and electrophysiological features that suggest an IEM in an epileptic patient.

Psychiatric manifestations revealing inborn errors of metabolism in adolescents and adults

Inborn errors of metabolism (IEMs) may present in adolescence or adulthood as a psychiatric disorder. In some instances, an IEM is suspected because of informative family history or because psychiatric symptoms form part of a more diffuse clinical picture with systemic, cognitive or motor neurological signs. However, in some cases, psychiatric signs may be apparently isolated. We propose a schematic classification of IEMs into three groups according to the type of psychiatric signs at onset. Group 1 represents emergencies, in which disorders can present with acute and recurrent attacks of confusion, sometimes misdiagnosed as acute psychosis. Diseases in this group include urea cycle defects, homocysteine remethylation defects and porphyrias. Group 2 includes diseases with chronic psychiatric symptoms arising in adolescence or adulthood. Catatonia, visual hallucinations, and aggravation with treatments are often observed. This group includes homocystinurias, Wilson disease, adrenoleukodystrophy and some lysosomal disorders. Group 3 is characterized by mild mental retardation and late-onset behavioural or personality changes. This includes homocystinurias, cerebrotendinous xanthomatosis, nonketotic hyperglycinaemia, monoamine oxidase A deficiency, succinic semialdehyde dehydrogenase deficiency, creatine transporter deficiency, and alpha and beta mannosidosis. Because specific treatments should be more effective at the 'psychiatric stage' before the occurrence of irreversible neurological lesions, clinicians should be aware of atypical psychiatric symptoms or subtle organic signs that are suggestive of an IEM. Here we present an overview of IEMs potentially revealed by psychiatric problems in adolescence or adulthood and provide a diagnostic strategy to guide metabolic investigations.

Peripheral neuropathy and inborn errors of metabolism in adults

Although they are classically viewed as paediatric diseases, it is now recognized that inborn errors of metabolism (IEMs) can present at any age from childhood to adulthood. IEMs can involve the peripheral nervous system, mostly as part of a more diffuse neurological or systemic clinical picture. However, in some cases, the neuropathy can be the unique initial sign. Here, based on our personal experience and on a comprehensive literature analysis, we review IEMs causing neuropathies in adults. Diseases were classified according to the predominant type of neuropathies into (1) acute neuropathies, (2) mononeuropathy multiplex, (3) chronic axonal polyneuropathies, (4) chronic demyelinating polyneuropathies, (5) small-fibre neuropathies, and (6) lower motor neuron disease.

Age at onset determines the occurrence of the progressive phase of multiple sclerosis

We investigated the influence of age at disease onset on timing of the progressive phase in 957 patients with multiple sclerosis (MS). Age at onset powerfully predicts the probability of developing a primary progressive form of the disease. Moreover, age at onset strongly determines the time to conversion to secondary progression for patients presenting with a relapsing form. This suggests that age at onset strongly influences the neurodegenerative component of MS.

Troubles neurologiques par carence en vitamine B12 déclenchés par le protoxyde d’azote

INTRODUCTION

Nitrous oxide is frequently used for anesthesia. It may cause spinal cord toxicity.

CASE REPORTS

We report two patients who presented gait disorders after nitrous oxide anesthesia. Physical examination revealed arms and legs pyramidal syndrome and abnormal proprioception, consistent with subacute combined degeneration of the spinal cord. Serum vitamin B12 level was extremely low. The patients improved with parenteral treatment with hydroxycobalamin.

CONCLUSIONS

The inactivation of methionine synthase and L methylmalonylcoA mutase by nitrous oxide has been previously demonstrated. Anesthesia-related exposure to nitrous oxide may induce neurologic disorders even in patients with no preliminary vitamin B12 deficiency.

[Adult onset hereditary leukoencephalopathies]

In clinical practice, the term "genetic leukoencephalopathy" refers to a group of genetic diseases whose common point is to give an aspect of diffuse leukoencephalopathy on MRI. With progress in diagnostic techniques including radiology, biochemistry or genetics, a large number of hereditary diseases causing leukoencephalopathy have been identified. Although generally beginning in childhood, these diseases often have more insidious clinical forms which can begin in adulthood. These forms remain poorly known. Some are accessible to treatment so their diagnosis appears essential. The diagnostic steps must be guided by clinical examination (neurological, ophthalmological and systemic), electromyography and MRI. The purpose of this review is to propose a classification of the genetic leukoencephalopathies and to give a progress report applicable in neurological practice.

[Isolated ptosis in a 58-year-old woman]

A 60-year-old woman who had experienced isolated ptosis for two years was seen when it had been fixed for one year. She had a personal and familial history of stromal corneal dystrophy. The diagnosis of mitochondrial cytopathy was made on the basis of clinical, electrophysiological, biological and histological findings. Surgical repair of the ptosis allowed visual recovery. The relationship between ptosis, corneal dystrophy and mitochondrial cytopathy is discussed.

Acute demyelination: an insight into the effect of mitoxantrone on CNS lesions

We report the cases of 2 severely disabled patients with large inflammatory lesions suggestive of demyelination treated with mitoxantrone. Clinical condition was improved and brain lesions volume was reduced. On serial MR spectroscopy, there were variations in peaks between 0.9 and 1.4 ppm, suggestive of free lipids and amino acids. These variations may represent neurochemical markers of clinical recovery of large inflammatory lesions in multiple sclerosis.

Hepatitis B vaccination and central nervous system demyelination: an immunological approach

Demyelination events or multiple sclerosis following hepatitis B virus (HBV) vaccination have been reported. We therefore compared the T-cell response to HBsAg in patients with CNS demyelination following HBV vaccination and in HBV-vaccinated healthy individuals. Our data showed no differences in terms of T-cell proliferation or cytokine production between these groups and may help to allay concerns that HBV vaccination might trigger a deleterious immune response.

A second-generation genomic screen for multiple sclerosis

Multiple sclerosis (MS) is a debilitating neuroimmunological and neurodegenerative disorder. Despite substantial evidence for polygenic inheritance of the disease, the major histocompatibility complex is the only region that clearly and consistently demonstrates linkage and association in MS studies. The goal of this study was to identify additional chromosomal regions that harbor susceptibility genes for MS. With a panel of 390 microsatellite markers genotyped in 245 U.S. and French multiplex families (456 affected relative pairs), this is the largest genomic screen for MS conducted to date. Four regions met both of our primary criteria for further interest (heterogeneity LOD [HLOD] and Z scores >2.0): 1q (HLOD=2.17; Z=3.38), 6p (HLOD=4.21; Z=2.26), 9q (HLOD; Z=2.71), and 16p (HLOD=2.64; Z=2.05). Two additional regions met only the Z score criterion: 3q (Z=2.39) and 5q (Z=2.17). Further examination of the data by country (United States vs. France) identified one additional region demonstrating suggestive linkage in the U.S. subset (18p [HLOD=2.39]) and two additional regions generating suggestive linkage in the French subset (1p [HLOD=2.08] and 22q [HLOD=2.06]). Examination of the data by human leukocyte antigen (HLA)-DR2 stratification identified four additional regions demonstrating suggestive linkage: 2q (HLOD=3.09 in the U.S. DR2- families), 6q (HLOD=3.10 in the French DR2- families), 13q (HLOD=2.32 in all DR2+ families and HLOD=2.17 in the U.S. DR2+ families), and 16q (HLOD=2.32 in all DR2+ families and HLOD=2.13 in the U.S. DR2+ families). These data suggest several regions that warrant further investigation in the search for MS susceptibility genes.

Very early onset AD with a de novo mutation in the presenilin 1 gene (Met 233 Leu)

The authors describe a 28-year-old woman with histopathologically confirmed early onset Alzheimer disease characterized by severe frontal lobe involvement associated with a de novo mutation in the presenilin 1 gene (PSEN1).

[Inflammatory optic neuropathy and multiple sclerosis]

The diagnosis of inflammatory optic neuritis remains essentially clinical, and may be improved by complementary investigations. The prognosis is related to the evolution of visual acuity and the risk of development of multiple sclerosis. The treatment of acute episodes is better precised but remains a matter of debate. Long term treatment has benefited from the results of recent MRI studies.

[Acute optic neuritis: clinical and MRI prognostic factors. Study of fifty patients]

The objective of this study was to evaluate the risk of visual outcome after acute optic neuritis (ON) in relation to clinical and MRI findings. Fifty cases of acute ON within one month were retrospectively studied. MRI with Short Tau Inversion Recovery (STIR) sequence of the optic nerve were obtained with a median time onset of 9 days after ON. Mean age of patients was 32.8 years, mean initial visual acuity was 3/10 and orbital pain was present in 86 percent100 of patients. The STIR sequence revealed lesion in 88 percent 100 of acutely symptomatic optic nerves. An initial low visual acuity (less than 2/10), the absence of orbital pain and involvement of the intracanalicular portion of the optic nerve on STIR sequence were statistically correlated with a poorer visual outcome (respectively p=0.0041, p=0.035 and p=0.011).

[Genetic factors in multiple sclerosis]

GENERAL DATA: The clinical manifestations and neuropathological signs of multiple sclerosis have been recognized for more than one hundred years, but the cause remains unknown.

EPIDEMIOLOGY

Multiple sclerosis is not evenly distributed throughout the world. There is an important north-south gradient in the northern hemisphere and inversely in the southern hemisphere; multiple sclerosis is more frequent in the higher altitudes. For a given latitude, there is a difference by ethnic origin. These observations indicate that multiple sclerosis is a multifactorial condition determined by both genetic and environmental factors.

STRATEGIES OF GENETIC STUDIES

Progress in our knowledge of the human genome and statistical analysis techniques have made it possible to search for genetic factors in multiple sclerosis using two complementary approaches. The first is by anonymous screening and the second is to search for a candidate gene. The HLA locus is the only one with an identified predisposing effect for multiple sclerosis. It only accounts for 10 to 20% of the genetic predisposition for multiple sclerosis and many factors remain to be discovered.

[Andermann syndrome in an Algerian family: suggestion of phenotype and genetic homogeneity]

Andermann syndrome or Agenesis of the Corpus Callosum with Polyneuropathy (MIM 218000) is an autosomal recessive disease almost exclusively found in Québec. Only few cases have been reported in other populations. The locus for Andermann syndrome was assigned to chromosome 15q13-q15 in French Canadian families. We performed a haplotype analysis with two markers of this chromosomal region in an Algerian consanguineous family with two affected sibs. The children were homozygous for both markers, suggesting genetic homogeneity in Andermann syndrome.

[The role of MRI in the diagnosis and the natural course of multiple sclerosis]

Magnetic resonance imaging (MRI) is very sensitive in depicting multiple sclerosis (MS) lesions, but its specificity is poor. New sequences such as fast spin echo and FLAIR (fluid attenuated inversion recovery) improve the detection of lesions. The exploration of the whole central nervous system, brain, optic nerves and spinal cord improves sensitivity and specificity. The existence of lesions at different ages responds to temporal dissemination. MRI has also allowed to better understand the natural history of MS, showing 5 to 10 times more radiological than clinical activity. In case of isolated demyelinating syndrome, MRI is the best predictor of the occurrence of definite MS and of the severity of disability in the subsequent 10 years. However, the diagnosis of MS remains clinical, and systematic control MRI are not useful in clinical practice.

Correlating multiple MRI parameters with clinical features: an attempt to define a new strategy in multiple sclerosis

MRI is the most powerful imaging technique in managing patients with suspected or confirmed multiple sclerosis (MS). However, conventional MRI variables show nonspecific abnormalities weakly correlated with clinical progression of the disease. New techniques, now routinely available, offer better characterisation of the pathophysiology. We combined conventional MRI, including lesion load, contrast enhancement and "black holes" with magnetisation transfer and diffusion-weighted imaging and localised proton MR spectroscopy (MRS) to study their relationship with disability, course and duration of MS. The variables that were the most significantly linked to the course of the disease (relapsing remitting versus secondary progressive) were lesion load, mean overall magnetisation transfer ratio and apparent diffusion coefficient (MGADC), the percentage of ADC in (PADCIMD), and out of (PAD-COMD) modal distribution, and the ratio N-acetylaspartate and creatine-containing compounds on MRS of the centrum semiovale. MGADC and PADCIMD were the independent factors most related to disability and duration of disease. Combining MRI techniques is clinically relevant and feasible for studies of MS and may be applied to other diseases of the central nervous system.

[A case of mitochondrial cytopathy (MERFF) without ragged red fibers at the onset]

We report a case of a mitochondrial cytopathy (MERRF) with a late diagnosis because of the absence of Ragged-Red Fibers (RRF) in the first muscular biopsy performed in childhood. Eight years after the onset of the disease the familial history and the clinical manifestations were very suggestive of a mitochondrial cytopathy and a second biopsy was performed confirming the diagnosis of MERRF. The authors discuss several hypotheses to explain the negativity of the first muscular biopsy. The absence of ragged-red fibers does not exclude the diagnosis of a mitochondrial cytopathy and other investigations are justified such as the biochemical study of the respiratory chain and the molecular analysis of mitochondrial DNA.

[Study with localized proton magnetic resonance spectroscopy of 31 multiple sclerosis lesions: correlations with clinical and MRI features]

We have analyzed with localized proton magnetic resonance spectroscopy (MRS) 31 lesions in 28 patients with multiple sclerosis (MS). The course of the disease was either relapsing remitting, secondary progressive, or primary progressive. Four patients had an isolated neurological syndrome suggestive of MS. The decrease in the NAA/Cre ratio and the raise of the Cho/Cre ratio were more pronounced in patients with an acute isolated neurological syndrome, suggesting the predominance of an inflammatory process, and the presence of an axonal dysfunction in the initial course of the lesion. The NAA/Cre ratio was negatively correlated with clinical disability and thus could be used as an index of disease activity. Patients with a secondary progressive course exhibited a significant increase in the Myo/Cre ratio compared to those with a relapsing remitting course. Thus, there may be an association between the evolution towards a progressive disease and axonal loss or the development of gliosis. The isointense lesions to the cerebrospinal fluid on MRI T1 weighted sequences were characterized by a sharp raise in the Cho/Cre ratio suggesting demyelination and/or intense inflammation. Gadolinium enhanced lesions were not characterized by a specific neurochemical profile.

A longitudinal study of callosal atrophy and interhemispheric dysfunction in relapsing-remitting multiple sclerosis

OBJECTIVES

To determine if callosal atrophy and interhemispheric dysfunction can be detected in the early stages of relapsing-remitting multiple sclerosis (MS) and to evaluate their progression in relation to the disability and evolution of lesions seen on magnetic resonance imaging during a 5-year period.

METHODS

We compared 30 patients who had clinically definite early-onset replasing-remitting MS and mild disability with control subjects. Regional and segmental callosal size and extent of white matter abnormalities on magnetic resonance imaging, as well as performance on tasks exploring interhemispheric transfer of motor, auditory, and sensory information were assessed. Patients with MS were evaluated at baseline and after 5 years. Physical disability was determined at both times using the Expanded Disability Status Scale score.

RESULTS

Patients with MS were seen with significant callosal atrophy and functional impairment of interhemispheric transfer at baseline that worsened during the 5-year study. A significant correlation was found between the magnitude of disability and the severity of morphological and functional callosal involvement at baseline. This association persisted at year 5. Baseline clinical characteristics such as age and prestudy relapse rate were unrelated to callosal size or interhemispheric performance. However, the number of baseline T2-weighted lesions was correlated with callosal involvement and this relation persisted at year 5.

CONCLUSION

Patients who had relapsing-remitting MS in the early stages of the disease and mild disability had significant callosal involvement that progressed over time. The relationship between disability, T2-weighted lesions load, and degree of morphological and functional callosal impairment confirm the potential value of using callosal dysfunction as a surrogate marker of disease progression in MS.

[Magnetic resonance spectroscopy in multiple sclerosis]

Magnetic resonance spectroscopy allows in vivo neurochemical exploration of multiple sclerosis (MS) lesions and normal appearing white matter on MRI. It gives insights into pathophysiology: inflammation (increase of choline), recent demyelination (increase in lipids and choline), axonal dysfunction (decrease of NAA), gliosis (increase of myoinositol). The spectroscopic profile of lesions is not specific to MS. Therefore MRI remains the first investigation to perform when MS is suspected. However, spectroscopy is a sensitive, reproducible, non invasive tool which may provide an index of activity. In the future, spectroscopy may contribute in homogenizing patient selection for clinical trials and might be used, in association with MRI, to evaluate therapeutic efficiency. Spectroscopy might also influence therapeutic choices by identifying the prevailing lesional mechanism: inflammation, demyelination, axonal destruction, or gliosis.

[The first episode of central nervous system demyelinization and hepatitis B virus vaccination]

BACKGROUND

Central nervous system (CNS) demyelinating episodes have been described following numerous vaccines but there is no definite conclusion about a causal relationship. Recently, in France, in the context of an Expanded Program on Immunization, several cases of CNS demyelination have been observed following injection of recombinant hepatitis B (HB) vaccine, leading to great concern.

METHODS

We performed a hospital-based case-control study of 121 patients with a first episode of CNS demyelination occuring between July 1993 and December 1995 and 121 age and sex matched controls seen in the same period. Data on vaccinations history of cases and controls were collected by a postal questionnaire and confirmed by a phone interview.

RESULTS

Adjusted odds ratio (OR) obtained from conditional logistic regression between a first episode of CNS demyelination and any vaccination were equal to 1.4 (95 p. 100 CI 0. 5-4.3) for an exposure within the 60 previous days and 2.1 (95 p. 100 CI 0.7-6.0) for an exposure within the 61-180 previous days. Similar results were found for HB vaccine exposure within the 60 previous days (adjusted OR=1.7, 95 p. 100 CI 0.5-6.3) or within the 61 to 180 previous days (adjusted OR= 1.5, 95 p. 100 CI 0.5-5.3).

CONCLUSION

These findings did not permit to exclude confidently an association between HB vaccine and the occurrence of a first CNS demyelinating episode.

Cytokines in genetic susceptibility to multiple sclerosis: a candidate gene approach. French Multiple Sclerosis Genetics Group

The immune system is involved in the pathophysiology of multiple sclerosis (MS) but the initiating antigen(s) is not yet identified. Since cytokines control both the intensity and the quality of the immune response they may be relevant candidates for the genetic susceptibility to MS. To analyze the contribution of type 1 and type 2 cytokine and cytokine receptor genes in the genetic susceptibility to MS, we have examined, in 116 French MS sibpairs, whether there is significant linkage between MS and 15 cytokine or cytokine receptor genes using 31 highly polymorphic genetic markers. The data were analyzed using the maximum likelihood score and the transmission disequilibrium approaches. None of the candidate genes tested was significantly linked to MS on the whole population. However, after stratification of the analysis on the basis of sharing (or not) of the HLA-DRB1*1501 allele, indication of linkage was found for the IL2-RB gene. These findings suggest that the IL2-RB locus contributes to the genetic susceptibility in a subgroup of MS patients.

Chromosome 17q22-q24 and multiple sclerosis genetic susceptibility. American-French Multiple Sclerosis Genetic Group

Recently, genome-wide searches for multiple sclerosis (MS) susceptibility genes have suggested that the chromosome 17q22-q24 region might contain susceptibility genes in two sets of families of different ethnic backgrounds (Finnish and British). Therefore, we decided to test this region in two sets of families of different ethnic backgrounds (American and French), but collected according to the same diagnostic criteria. All lod-score values were non-significant. Moreover, we could exclude that the 17q22-24 region might contain a gene increasing the sibling recurrence risk of MS over 1.4, rendering the existence of such a gene very unlikely, at least in the group of tested families.

Normal-appearing white matter in optic neuritis and multiple sclerosis: a comparative proton spectroscopy study

We investigated neurochemical abnormalities in the normal-appearing white matter (NAWM) on MRI of patients with optic neuritis (ON) and compared them to those of patients with multiple sclerosis (MS). Patients with ON (42) were classified into three groups according to abnormalities on brain MRI. Patients with MS (55) were divided in two groups: relapsing remitting MS (RRMS) and secondary progressive MS (SPMS). All patients underwent MRI of the brain and localised proton magnetic resonance spectroscopy (MRS) of NAWM. The results were compared to those of 15 controls. Patients with MS had significant abnormalities compared with controls and with patients with ON. Patients with RRMS and those with ON had comparable MRS parameters, while patients with SPMS had significant spectroscopic abnormalities in comparison with controls, but also with patients with RRMS. These changes consisted of a decrease in N -acetylaspartate, a neuronal marker, which may reflect axonal dysfunction and/or loss. MRS abnormalities were detected in 14 patients with ON (27 %). The main abnormalities consisted of a decrease in N -acetylaspartate, an increase in choline-containing compounds at long echo times, and the presence of free lipid peaks at short echo times. MRS of the NAWM on MRI may prove useful for detecting neurochemical brain abnormalities in ON not visible on MRI.

Localized proton magnetic resonance spectroscopy in relapsing remitting versus secondary progressive multiple sclerosis

OBJECTIVE

To determine the efficacy of MRS in discriminating between relapsing remitting (RR) and secondary progressive (SP) MS.

METHODS

MRS at long and short echo times was carried out in 104 patients with MS stratified for clinical course (RR or SP), and the results were compared with those of 15 control subjects. Normal-appearing white matter (NAWM) was studied in 55 patients, and a high-T2-signal area on MRI in 49 others.

RESULTS

At long echo times, there was a highly significant decrease in the ratios N-acetyl-aspartate/creatine (NAA/Cr) and NAA/ choline (Cho) in high-T2-signal areas and in the NAWM in patients with an SP course compared with control subjects and patients with an RR course. There was a significant negative correlation between these ratios and clinical disability measured by Expanded Disability Status Scale score, which was independent of disease duration. Discriminant values between patients with RR and SP courses were found in the NAWM (NAA/Cr = 1.75 and NAA/Cho = 1.5), but not in high-T2-signal areas. At short echo times, there was a significant increase in the ratio myoinositol/Cr in high-signal areas of patients with an SP course compared with control subjects, and the presence of abnormal resonances in the lesions and NAWM for free amino acids and lipids (in 30% and 8%, respectively) and GLX complex (glutamine, glutamate, gamma-aminobutyric acid; 16% and 20%, respectively).

CONCLUSIONS

Studying normal-appearing white matter on MRI with MRS allows discrimination between relapsing remitting and secondary progressive patients. In the NAWM of patients with MS and an SP course, severe axonal loss/dysfunction is negatively correlated to clinical disability and independent of the duration of the disease.

Encephalitis after hepatitis B vaccination: recurrent disseminated encephalitis or MS?

OBJECTIVE

To describe clinical and MRI features of patients with a disease suggestive of CNS inflammation after hepatitis B vaccination.

METHODS

Eight patients with confirmed CNS inflammation occurring less than 10 weeks after hepatitis B vaccination are described. They received follow-up clinically and on MRI for a mean period of 18 months.

RESULTS

Clinical and MRI findings were compatible with acute disseminated encephalomyelitis. However, clinical follow-up, repeated MRI, or both showed the persistence of inflammatory activity, which makes this encephalitis more suggestive of MS than of acute disseminated encephalomyelitis.

CONCLUSION

The persistent inflammatory activity observed clinically and on MRI in these patients is comparable with that usually observed in MS. Epidemiologic studies are currently testing the hypothesis of a triggering role of hepatitis B vaccination in CNS demyelination.

Familial factors influence disability in MS multiplex families. French Multiple Sclerosis Genetics Group

BACKGROUND

Both genetic and environmental factors play a role in the pathophysiology of MS and may influence the clinical expression of the disease.

OBJECTIVE

To determine the contribution of familial factors to the clinical expression of MS.

METHODS

The French Multiple Sclerosis Genetics Group identified 87 sibling pairs. For each patient, sex, age at onset, duration of the disease, and disease course from onset were recorded. Disability was determined by the progression index (PI), defined as the ratio of the Expanded Disability Status Scale (EDSS) score disease duration when the latter exceeded 5 years. Statistical analyses were performed either with a group of patients (clinical features, relation between human leukocyte antigen and clinical features) or with a group of sibpairs (concordance for clinical features).

RESULTS

The mean age at onset was 29.6 years, the ratio of women to men was 59:28, and the mean PI was 0.27. There was no correlation for disease course and age at onset between sibs with MS. In contrast, we observed a weak but significant correlation of the PI in MS sibpairs (r = 0.234, p = 0.03).

CONCLUSION

This study revealed a concordance in MS sibling pairs for the disease severity, supporting the hypothesis that the degree of disability might be partly influenced by familial factors (environmental or genetic).

A systematic study of oligodendrocyte growth factors as candidates for genetic susceptibility to MS. French Multiple Sclerosis Genetics Group

OBJECTIVE

To test 23 genes coding for growth factors and their receptors as candidates for MS genetic susceptibility in 84 multiplex families of French origin by linkage analysis.

BACKGROUND

Epidemiologic studies have indicated that genetic susceptibility in MS exists. To identify MS susceptibility genes, association and linkage studies were performed with candidate genes suggested by the pathology of MS. The most consistent result was genetic association and linkage of MS to human leukocyte antigen (HLA) DR15. Recent advances in the knowledge of MS pathology have suggested that the oligodendrocyte, the myelin-forming cell in the CNS, and its growth factors might play a crucial role in MS.

METHODS

Fifty-two polymorphic markers within or flanking 23 candidate genes were used. Data were analyzed with the maximum likelihood score (MLS) approach. We also searched for a genetic interaction with HLA.

RESULTS

Negative results were obtained for all candidate genes. The lower limits of the relative risk (Xs) possibly excluded for any candidate gene ranged from 1.3 to 2.8. Positive MLS values (up to 0.93) were observed for transforming growth factor beta 3 (TGFbeta3) in HLA DR15-associated families, suggesting a possible role for this growth factor in interaction with HLA.

CONCLUSIONS

Oligodendrocyte growth factors do not play a significant role in MS genetic susceptibility, at least in the tested sample. TGFbeta3, the only gene highlighted by this study, deserves further analysis.

Apolipoprotein E and multiple sclerosis: a biochemical and genetic investigation

Apolipoprotein E (apo E) is postulated to be a major lipid carrier protein in the brain involved in brain development and repair. Multiple sclerosis (MS) is a major demyelinating disease characterized by destruction of myelin and marked alteration of myelin cholesterol and lipid metabolism. We have determined serum and cerebrospinal fluid (CSF) apo E concentrations using an original time-resolved immunofluorometric assay and calculated intrathecal apo E concentration. Apo E concentrations were determined in 13 control subjects and 129 neurological patients: 34 definite MS patients, 25 with Guillain-Barré syndrome (GBS), 32 with amyotrophic lateral sclerosis (ALS) and 38 with other neurological diseases. Seven clinical parameters (sex, age, age at MS onset, duration of the disease, course, clinical status and disability score) were considered in MS patients. Significant (P < 0.01) decrease in CSF apo E was observed in MS, linked to a decrease in intrathecal apo E. The decreased CSF apo E concentration in MS patients occur independent of the apo E genotype. Apo E is considered as a neurotrophic factor in the brain. Any decrease in intrathecal apo E synthesis would thus contribute to progression of neurological diseases, such as MS.

T cell receptor V beta 5 and V beta 17 clonal diversity in cerebrospinal fluid and peripheral blood lymphocytes of multiple sclerosis patients

To better characterize the cellular immune response taking place in the MS central nervous system, we investigated the blood and CSF T cell receptor (TCR) V beta 5 and V beta 17 repertoire in HLA-typed patients with recently diagnosed MS or other neurological diseases (OND). Using a RT-PCR based technique, we analysed directly ex vivo the CDR3 size of TCR beta chains utilizing V beta 5 (eight patients with MS and one with OND) or V beta 17 (eight patients with MS and six with OND) gene segments on paired blood-CSF samples. Globally, the analysis of V beta 5-J beta and V beta 17-J beta repertoire showed a less diverse pattern in the CSF samples than in the corresponding peripheral blood lymphocytes both in MS and in OND patients. However, we did not detect any recurrent clonal expansion within the V beta 5+ T cells in MS patients, underlining the potential limits of V beta 5-based immunotherapy in MS. We found an expanded T cell population using the same V beta 17-J beta 1.6 combination with identical CDR3 length in the CSF of three MS patients and none of the control patients. These results suggest selective expansion of T cells expressing this segment gene in the MS central nervous system.