Interferon beta-1b exacerbates multiple sclerosis with severe optic nerve and spinal cord demyelination

To evaluate the effect of interferon beta-1b (IFNB-1b) on multiple sclerosis (MS) with severe optic nerve and spinal cord demyelination, we examined the relationship between IFNB-1b treatment outcome and the clinical and genetic characteristics of three types of demyelinating diseases of the central nervous system, i.e., neuromyelitis optica (NMO), MS and MS with severe optic-spinal demyelination. Japanese MS frequently carried HLA DPB1*0501, which is associated with NMO. MS with DPB1*0501 showed severe optic-spinal demyelination represented by longitudinally extensive spinal cord lesion, blindness and CSF pleocytosis. IFNB-1b treatment did not succeed in these patients because of the increase of optic nerve and spinal cord relapse and other severe side effects. IFNB-1b should not be administered to demyelinating patients with genetic and clinical characteristics mimicking NMO such as HLA DPB1*0501 allele, longitudinally extensive spinal cord lesion, blindness and CSF pleocytosis even if they have symptomatic cerebral lesions as typically seen in MS. The present study strongly suggests that these patients should be diagnosed as having NMO.     

Molecular immunogenetic approach to the pathogenesis of multiple sclerosis]

In Japanese, there is no association of susceptibility to multiple sclerosis with any HLA class II alleles as a whole group. However, when we clinically classified MS patients into those having opticospinal form MS which presented selective involvement of the optic nerve and spinal cord and those with conventional form MS showing multiple involvement of the central nervous system including cerebrum, cerebellum and brainstem, the former showed a significant association with HLA-DPB1*0501 allele while the latter had an association with HLA-DRB1*1501 allele. The patients with opticospinal form MS showed a marked Th1/Tc1 shift both in the relapse phase and in the remission phase, as determined by an intracellular IFN-gamma/IL-4 ratio in peripheral blood CD4+ T cells and CD 8+ T cells. These findings suggest that opticospinal form MS is also an organ-specific autoimmune disease associated with a distinct HLA allele. By using SEREX method and brain proteomics approach, we have thus searched for any relevant autoantigens in the central nervous system in Japanese patients with MS. Heat shock proteins and neural proteins are found to be possible new candidate autoantigens in Japanese patients with MS.     

Abnormal cervical vestibular-evoked myogenic potential in anterior inferior cerebellar artery territory infarction: frequency, pattern, and a determinant

BackgroundThere have been few magnetic resonance imaging (MRI) studies of the spinal cord in large multiple sclerosis (MS) patient cohorts and little is known about correlations between cord lesions and human leukocyte antigen (HLA) alleles.ObjectiveTo investigate the spectrum of MRI changes in the spinal cord in MS and associations with the HLA-DRB1 genotype.MethodsTwo hundred and fifty two consecutive MS patients from the Perth Demyelinating Diseases Database had MRI of the spinal cord and brain and high-resolution HLA-DRB1 genotyping. The numbers, locations, shape and segmental extent of cord lesions were analysed and were correlated with carriage of individual HLA-DRB1 alleles and diplotypes.ResultsFocal cord lesions were present in 82.9% of cases, with numbers being maximal in the cervical cord and increasing with disease duration. Focal lesions were usually round or oval in shape but in 35% of cases subpial wedge-shaped lesions were present. Diffuse cord involvement was present in 10% of cases and correlated with carriage of HLA-DRB1*1501 and with higher disability. Carriage of the minor allele HLA-DRB1*0701 was significantly associated with numbers of wedge-shaped lesions and lesions in the cervical cord, while HLA-DRB1*1104 and DRB1*0103 were significantly associated respectively with higher and lower numbers of thoracic cord lesions. HLA-DRB1*1501 and the HLA-DRB1*11 sub-alleles DRB1*1101 and DRB1*1104 were significantly associated with the segmental length of cord lesions.ConclusionsOur study is the first to investigate the frequency of subpial wedge-shaped lesions in the cord in vivo and has provided preliminary evidence that HLA-DRB1 alleles may play a role in determining the severity and extent of spinal cord involvement in MS.     

Multiple sclerosis amongst Chinese in Taiwan.

Twenty-five cases of multiple sclerosis (MS), including 2 autopsy cases, collected during the past 20 years from amongst the Chinese of Taiwan, are reported. These cases fulfilled all the clinical diagnostic criteria of MS. The following observations were made: (1) Multiple sclerosis does exist among Chinese in Taiwan. It is uncommon, but is by no means a very rare disease. The prevalence rate in northern Taiwan near Taipei is estimated as 0.8/100.000 population. (2) Female preponderence was conspicuous (F:M = 3.2.:1) in our MS cases as well as in other demyelinating diseases. (3) On the whole, the onset of the disease was earlier in female patients, and those who had their initial symptoms before the age of 20 years were all females. (4) The optic nerve was most frequently involved at the onset, and it was involved in the majority of patients during the whole clinical course. (5) Involvement of the optic nerve and spinal cord, with or without the brain stem, was the commonest form of our MS cases, especially among female patients. (6) More malignant forms of MS, with acute onset and rapid clinical course leading to severe incapacity or fatality, were more common among female patients. (7) Painful tonic spasms were relatively frequently encountered, and they were usually seen in patients with severe spinal cord involvement. (8) Marked elevation of the CSF total protein and of leukocytes was relatively frequent during severe relapses in patients with spinal cord lesions. (9) Severe and extensive demyelinating lesions, both old and recent, in the optic nerve and spinal cord were seen in 2 autopsy cases. The relationship between MS and NMO in Oriental patients is briefly discussed. (10) It seems likely that cases of MS which are atypical as compared with Western MS are more frequently seen in Oriental countries, and perhaps also in tropical regions where MS is known to be rare.     

人类白细胞抗原DRB1基因与多发性硬化遗传易患性研究

目的　分析多发性硬化遗传易患的分子免疫遗传背景。方法　采用聚合酶链反应序列特异性引物（ＰＣＲＳＳＰ） 联合技术对４５ 例病例组和１０５ 例正常对照组人类白细胞抗原ＤＲＢ１ 基因（ＨＬＡＤＲＢ１） 进行基因分型。结果　病例组ＨＬＡＤＲ２ 基因频率高于正常对照组，优势比为３．３２１ ，有统计学意义（ Ｐ＜ ０．０１）。结论　ＨＬＡＤＲ２ 基因与多发性硬化遗传易患相关联，提示可能还存在保护性基因。     

Western versus asian types of multiple sclerosis: Immunogenetically and clinically distinct disorders

The polymorphism of HLA-DRBI, -DRB3, and -DRB5 genes as well as magnetic resonance images of the brain and spinal cord were studied in 57 Japanese patients with multiple sclerosis (MS). Twenty-three patients clinically displayed selective involvement of the optic nerve and spinal cord and were classified as having Asian-type MS. Patients with Asian-type MS had fewer brain lesions shown gy magnetic resonance imaging, but more gadolinium-enhanced spinal cord lesions than did patients with Western-type MS (47% vs 17%). Fruthermore, the DR2-associated DRBI1501 allele and DRB50101 allele were associated with Western-type MS (41.2%), but not with either Asian-type MS (0%) or healthy control subjects (14.2%). Heterogeneity inthe immunogenetic background and in the magnetic resonance imaging features between the two subtypes of MS thus suggests the presence of two etiologically distinct diseases in Asians.     

A central demyelinating disease with atypical features

There are clinical, laboratory and imaging criteria to distinguish multiple sclerosis (MS) from neuromyelitis optica (NMO) and acute disseminated encephalomyelitis (ADEM). While MS has unknown aetiology, NMO is commonly associated with vasculitis and ADEM is supposed to be parainfectious in origin. In the present study, six patients are described from a group of 67 with a central demyelinating disorder whose clinical presentation did not conform to existing diagnostic criteria for ADEM, NMO or MS. Their clinical, laboratory and imaging characteristics were studied and analysed. Some features suggested a particular diagnosis but some other features favoured another diagnosis. The features included spinal cord involvement in a large vertical segment with cord swelling, optic neuritis, no lesions in the cerebral cortex, paraplegia with urinary retention during the acute phase, no oligoclonal band in cerebrospinal fluid, absence of any evidence of vasculitis, wide time-gap between spinal cord and optic nerve involvement, good recovery from acute phase of disease and a relatively benign course. We conclude that there exists a subpopulation of patients with central demyelinating disease in this region with mixed clinical features. Overall features suggested either a widened clinical spectrum of MS, NMO or ADEM or a possible overlap between them.     

The clinical course of neuromyelitis optica (Devic's syndrome).

OBJECTIVES: To evaluate the spectrum of neuromyelitis optica (NMO), including characteristics of the index events (optic neuritis [ON]) and myelitis), neuroimaging, CSF, and serologic studies, and to evaluate the long-term course. METHODS: Review of 71 patients with NMO evaluated at the Mayo Clinic between 1950 and 1997. RESULTS: NMO was either monophasic or relapsing. Patients with a monophasic course (n = 23) usually presented with rapidly sequential index events (median 5 days) with moderate recovery. Most with a relapsing course (n = 48) had an extended interval between index events (median 166 days) followed within 3 years by clusters of severe relapses isolated to the optic nerves and spinal cord. Most relapsing patients developed severe disability in a stepwise manner, and one-third died because of respiratory failure. Features of NMO distinct from "typical" MS included >50 cells/mm3 in CSF (often polymorphonuclear), normal initial brain MRI, and lesions extending over three or more vertebral segments on spinal cord MRI. CONCLUSIONS: Clinical, laboratory, and imaging features generally distinguish neuromyelitis optica from MS. Patients with relapsing optic neuritis and myelitis may have neuromyelitis optica rather than MS. Patients with a relapsing course of neuromyelitis optica have a poor prognosis and frequently develop respiratory failure during attacks of cervical myelitis.     

Idiopathic severe recurrent transverse myelitis: a restricted variant of neuromyelitis optica

Recurrent idiopathic transverse myelitis occur in multiple sclerosis (MS) and neuromyelitis optica (NMO). In NMO, acute optic neuritis and myelitis occur, either monophasic or relapsing, without clinical manifestations of involvement of other parts of the central nervous system (CNS). Recent evidence suggests that NMO is different from multiple sclerosis. The authors reported two patients having severe recurrent transverse myelitis sparing the optic nerves and cerebral hemispheres. Both patients had longitudinally extensive myelitis in some attacks with poor neurological outcome despite aggressive immunomodulatory therapy. One patient had prominent clinical features of brainstem injury with radiological and histological confirmation of brainstem involvement, and the other patient had trigeminal neuralgia suggestive of possible brainstem dysfunction. Histologically, prominent necrosis and neutrophilic infiltration of spinal cord tissue without eosinophils or hyalinized vessels were observed, and oligoclonal bands were absent in their cerebrospinal fluid. It is likely to be a distinct idiopathic inflammatory demyelinating disorder restricted to the spinal cord and brainstem different from MS, but within the spectrum of NMO with probably an autoimmune basis.     

Influence of HLA on progression of optic neuritis to multiple sclerosis: results of a four-year follow-up study

BACKGROUND: Genetic predisposition in multiple sclerosis (MS) has always been a critical concern in aetiology and progress of the disease. The present study looks into the relations between human leukocyte antigen (HLA), optic neuritis (ON) and MS in the Iranian population. METHODS: Patients with potential diagnosis of acute ON underwent a standardized clinical examination for confirming the diagnosis. Selected patients were gathered for HLA typing and clinical follow up. RESULTS: Of the 55 patients, 46 (83.6%) were female. The mean age was 25(+/-7.3) with a range of 12-43. Twenty of the 55 (36%) were confirmed for the diagnosis of clinically definite MS (CDMS). Results show that A23, B21, A11 and B51 alleles were present in 4 (20%), 6 (30%), 2 (10%) and 1 (5%) of the CDMS patients, respectively. Ten (50%) and 17 (85%) CDMS patients were positive for HLA class II alleles, DR2 and DQ1, correspondingly. CONCLUSIONS: The study strongly suggests the association among DR2, A23 and B21 allele and the evolution of ON to MS. High prevalence of A23 and DR2 alleles in CDMS patients compared with the normal population may suggest an important role for these alleles in the development of MS. The study suggests B51 as a protective factor against development of ON in the normal population. In addition, results do not confirm previous studies considering A11 as a predisposing factor. The present study finally evokes that different classes of HLA have different roles in susceptibility to MS and confirms disease heterogeneity as an important emerging concept in MS.     

视神经脊髓炎临床与病理

目的：分析视神经脊髓炎（NMO）的特征。方法：对114例NMO患者的临床资料,3例尸检结果,28例随访情况进行研究。结果：该病患者男女之比为1：2．5,发病年龄以12－50岁居多（85％）,急性和亚急性起病占大多数（74．84％）,视神经症状为首发占58．77％,视神经与脊髓症状的间隔时间在1年内者60例,占52．33％。脊髓以横贯性损害为主,有95例（83．33％）,以胸段损害最多（64．33％）,尸体解剖例2、3为NMO;病程中有缓解－复发者65例,其中有14例发展为多发性硬化,包括尸体解剖例1。结论：NMO有两种类型;复发型中有一小部分可发展成为MS,MRI,脑干视觉诱发电位和长期随访有利于NMO和MS的鉴别。     

DQB1*0602 allele shows a strong association with multiple sclerosis in patients in Malaga,Spain

BACKGROUND: The human leukocyte antigen (HLA) class II DR2 haplotype (DRB1*1501, DQA1*0102, DQB1*0602) has been associated with multiple sclerosis (MS) in all ethnic groups and very strongly in Caucasians. AIM: To investigate the possible HLA class II (DRB1, DQA1 and DQB1) associations with MS in Malaga, southern Spain. METHODS: We analysed the HLA class II sub-regions DRB1, DQA1 and DQB1 by polymerase chain reaction (PCR) and sequence-specific oligonucleotide probe hybridization (PCR/SSO) for DRB1 and DQB1 and with sequence-specific primers (PCR/SSP) for DRB1 subtypes and DQA1. Possible HLA class II associations with clinical MS characteristics were investigated in 149 subjects with and 160 without MS. RESULTS: Associations were detected between MS and the HLA class II alleles DRB1*1501 (45.6 % vs. 21.3%, p=0.001), DQA1*0102 (44% vs. 29.4%, p=0.001) and DQB1*0602 (45% vs. 20.6%, p=0.001). The DR2 haplotype (DRB1*1501, DQA1*0102, DQB1*0602) was associated with MS (43.6 % vs. 20%, p=0.002). DQB1*0602 was the only allele that maintained an association with MS in a logistic regression model. No HLA class II alleles or genotypes were significantly associated with any clinical characteristics of MS. CONCLUSIONS: Our results confirm the positive association of the DR2 haplotype with MS, particularly the allele DQB1*0602, in the population studied. DR4 was not associated with the disease in Malaga. HLA class II alleles or haplotypes were not associated with clinical or demographic characteristics, or clinical form or severity of MS.     

Association of HLA‐DRB1*15 allele and CSF oligoclonal bands in a Spanish multiple sclerosis cohort

Background and objective: The HLA‐DRB1*15 allele is consistently associated with multiple sclerosis (MS) susceptibility in most studied populations. This study investigated the association between HLA‐DRB1 alleles and the presence of oligoclonal immunoglobulin G bands (OCB) in the cerebrospinal fluid (CSF) in a Spanish population with MS. Methods: The HLA‐DRB1 typing was performed in 268 patients with sporadic MS and the detection of OCB in CSF. HLA‐DRB1 allelic frequencies were compared between OCB‐positive and OCB‐negative patients, and both groups were also compared with 1088 unrelated healthy controls. Moreover, we correlated the various HLA‐DRB1 genotypes, considering all the combinations of both parental alleles found with the presence or absence of OCB. Results: We found 206 OCB‐positive and 62 OCB‐negative patients. The HLA‐DRB1*15 allele in OCB‐positive patients had a higher frequency when compared with OCB‐negative patients (39.3% in OCB‐positive vs. 16.1% in OCB‐negative, OR = 1.38 95% CI = 1.18–1.61, P < 0.001). The other alleles did not show differences. When we compared with controls, the HLA‐DRB1*15 allele was associated with the disease only in the OCB‐positive patients group. None of the 55 genotypes found showed any association with the presence or absence of OCB. Conclusions: HLA‐DRB1*15 allele is associated with OCB‐positive patients with MS when studying a Spanish MS population.     

HLA‐DRB1: genetic susceptibility and disability progression in a Spanish multiple sclerosis population

Background and objective: The association of HLA‐DRB1*15 with susceptibility to multiple sclerosis (MS) has been consistently reported although its effect on the clinical phenotype is still controversial. The objectives of this study are to investigate the influence of the HLA‐DRB1 alleles on the genetic susceptibility to MS and to study their impact on disability progression in a Spanish population. Methods: HLA‐DRB1 typing was performed by PCR‐SSP in 380 patients with sporadic MS and 1088 unrelated healthy controls. Allelic frequencies were compared between groups. We studied the correlation between the different alleles and the progression of MS. Results: The HLA‐DRB1*15 allele in patients with MS had a statistically significant higher frequency when compared with controls (18.9% in patients vs. 10.1% in controls, Odds ratio (OR) = 2.07, 95% CI = 1.64–2.60, P < 0.001). In the univariate analysis, the DRB1*01 and DRB1*04 alleles were associated with a worse prognosis when considering the time to reach an EDSS of 6, whereas the DRB1*03 was correlated with a better outcome. In the multivariate analysis, the alleles*01 and *04 were demonstrated to be independent factors to have a worse prognosis. Conclusions: HLA‐DRB1*15 is associated with MS when comparing patients with unrelated healthy controls in a Spanish population. The HLA‐DRB1*01 and HLA‐DRB1*04 alleles are related to a worse prognosis when considering the time taken to reach severe disability.     

Spinal cord MRI in clinically isolated optic neuritis

BACKGROUND/METHODS: One hundred and fifteen patients with clinically isolated optic neuritis underwent magnetic resonance imaging (MRI) of the brain and spinal cord within 3 months of the onset of symptoms. RESULTS: Eighty one (70%) patients had brain lesions and 31 (27%) had cord lesions. Cord lesions were seen in 12% with a normal brain MRI, 21% with between one and eight brain lesions, and 45% with nine or more brain lesions. When the new diagnostic criteria for MS were applied, MRI cord imaging used for evidence of dissemination in time and space allowed a diagnosis of MS in only one additional asymptomatic patient at 1 year, two additional asymptomatic patients at 3 years. CONCLUSIONS: Using existing criteria, spinal cord imaging rarely contributes to the diagnosis in patients with clinically isolated optic neuritis.     

Clinically isolated syndromes

Clinically isolated syndrome (CIS) is a term that describes a first clinical episode with features suggestive of multiple sclerosis (MS). It usually occurs in young adults and affects optic nerves, the brainstem, or the spinal cord. Although patients usually recover from their presenting episode, CIS is often the first manifestation of MS. The most notable risk factors for MS are clinically silent MRI lesions and CSF oligoclonal bands; weak or uncertain risk factors include vitamin D deficiency, Epstein-Barr virus infection, smoking, HLA genes, and miscellaneous immunological abnormalities. Diagnostic investigations including MRI aim to exclude alternative causes and to define the risk for MS. MRI findings incorporated into diagnostic criteria in the past decade enable MS to be diagnosed at or soon after CIS presentation. The course of MS after CIS is variable: after 15-20 years, a third of patients have a benign course with minimal or no disability and a half will have developed secondary progressive MS with increasing disability. Prediction of the long-term course at disease onset is unreliable. Disease-modifying treatments delay the development from CIS to MS. Their use in CIS is limited by uncertain long-term clinical prognosis and treatment benefits and adverse effects, although they have the potential to prevent or delay future tissue damage, including demyelination and axonal loss. Targets for future therapeutic progress are to achieve safe and effective long-term immunomodulation with neuroprotection and repair.     

Multiple sclerosis-associated retrovirus and optic neuritis

One prognostic factor for early multiple sclerosis (MS) patients to develop a definite MS may be the presence of the MS-associated retrovirus (MSRV) in the cerebrospinal fluid (CSF). We designed a specific study on a cohort of optic neuritis (ON) patients to evaluate the MSRV-dependent conversion to MS relative to the prediction conferred by magnetic resonance imaging (MRI) and CSF abnormalities. At follow-up, 33.3% MSRV+ and 0% MSRV- ON patients developed MS (P = 0.03). The prediction value is lower than that given by CSF and MRI abnormalities (42.3%). This intriguing finding is discussed in the light of the abundant discrepancies observed in the MSRV literature. Multiple Sclerosis 2006; 12: 357-359. www.multiplesclerosisjournal.com     

Two unusual neuropathologically proven cases of multiple sclerosis from bombay

Two unusual cases of multiple sclerosis (MS), both from Bombay, have been reported with detailed clinical and histopathological findings, which evidenced dissemination in time and in space. They were both women in their twenties, with total duration of the neurological illness of 5–6 months.

The first patient had initial signs related to the optic nerves and then, after remission, to the brain stem and spinal cord. There were chronic plaques in the medulla, in 1 optic nerve and lesions of varying stages throughout the cervical spinal cord, with glial cellular and fibrillar reaction, and some preservation of axons. This appeared to be a case of MS with features simulating neuromyelitis optica.

The second patient had initial signs related to the lumbar cord, like a transverse myelitis and then, after a remission, evidence of a progressive cerebral disorder with clinical and ventriculographic findings suggesting a space-occupying lesion in the corpus callosum and frontal lobes. The more chronic demyelination was in the spinal cord. The brain showed large, recent, symmetrical, periventricular plaques, with total absence of myelin except in some of the U-fibres, throughout the frontal and parietal lobes and anterior corpus callosum. There was moderate lymphocytic reaction in and around the vessels, extensive accumulation of myelin breakdown products in histiocytes (gemistocytes and gitter cells) with some preservation of axons and early gliosis. This appeared to be a case of MS with some features of diffuse cerebral sclerosis, or what is often called transitional type of MS.

A history of smallpox vaccination 5 weeks before the illness in the first case, and the chronic inflammatory reaction in the second, together with the rapid tempo of the disease in both, which determined the characteristic patterns of clinical and pathological changes, has led us to discuss the infectious and allergic hypotheses of aetiology in MS.     

HLA class II susceptibility to multiple sclerosis among Ashkenazi and non-Ashkenazi Jews.

OBJECTIVE: To look for HLA class II alleles and haplotypes conferring susceptibility to multiple sclerosis (MS) in the Jewish population of Israel. DESIGN: Population-based cohort of clinically definite patients with MS tested prospectively over 7 years. SETTING: Referral center in a neurology clinic at a university hospital in the greater Jerusalem area in Israel. PATIENTS: A total of 162 consecutive patients with clinically definite MS from the 2 main ethnic Jewish groups in Israel: 104 Ashkenazi (80 with a relapsing remitting or secondary progressive and 24 with a primary chronic progressive course of the disease) and 58 non-Ashkenazi (36 with a relapsing remitting or secondary progressive course and 22 with a primary chronic progressive course of the disease), matched with 132 Ashkenazi and 120 non-Ashkenazi healthy controls. MAIN OUTCOME MEASURES: The relationship between the various HLA class II alleles and haplotypes and MS, as defined by the polymerase chain reaction and sequence-specific oligonucleotide probe hybridization, among the Ashkenazi and the non-Ashkenazi Jewish sections and with respect to the different clinical courses of the disease. RESULTS: The haplotype DRB1*1501, DQA1*0102, DQB1*0602 was found to be associated with MS among both Ashkenazi and non-Ashkenazi patients (P<.001 and P =.04, respectively). Among the non-Ashkenazi patients, a new association of haplotypes DRB1*1303, DQA1*05, and DQB1*030 with MS was detected (P = .03). The MS susceptibility alleles, DRB 1* 1501, DQA1*0102, and DQB1*0602 , were found in association with the Ashkenazi patients (P<.001, P=.02, and P=.01, respectively); DRB1*1501 and DRB1*1303 were more frequently observed among the non-Ashkenazi patients (P = .03, P = .04, respectively). On subdivision of the patients into clinical subgroups, associations of DRB1*0801, DQA1*0102, DQA1*0401, and DQB1*0602 with primary chronic progressive MS among the Ashkenazi patients were evident (P = .03, P = .04, P = .04 and P = .05, respectively), whereas DRB1* 1501, DRB1*03011, and DQB1*0602 were associated with relapsing remitting or secondary progressive among the non-Ashkenazi patients (P = .05, P = .05, and P = .03, respectively). CONCLUSIONS: This study, unlike previous ones, is the first to show a significant association between HLA class II alleles and MS in the Jewish population. The association with the HLA-DR2-related haplotype is similar to that among non-Jewish white patients with MS. Moreover, our data support the possibility that DRB1*1501 is the susceptibility allele responsible for the association between this haplotype and MS in the Jewish population. Our study also underscores differences in HLA profiles between Ashkenazi and non-Ashkenazi patients, and between the different clinical courses of the disease. The latter may indicate that the clinical courses of MS are influenced by the genetic background.