Multiple Sclerosis Journal

Magnetic resonance imaging (MRI) has had a profound impact on both research and clinical management of multiple sclerosis (MS), but signal changes reflect underlying neuropathology only indirectly and often non-specifically. Positron emission tomography (PET) offers the potential to complement MRI with quantitative measures of molecularly specific markers of cellular and metabolic processes. PET radiotracers already available promise new insights into the dynamics of the innate immune response, neuronal function, neurodegeneration and remyelination. Because PET is an exquisitely sensitive technique (able to image even picomolar concentrations), only microdoses of radioligand (<10 µg) are needed for imaging. This facilitates rapid implementation of novel radioligands because extensive toxicology data is not required. In the future, molecular imaging could assist clinical decision-making with patient stratification for optimization of treatment selection.

Background and Objective: The objective of this study was to determine the prevalence and incidence of multiple sclerosis (MS) and its temporal profiles from 1975 to 2005 in the city of Catania.

Methods: The incidence of MS from 1975 to 31 December 1999 had been previously investigated by the same group. The frequency of MS in the community of Catania from 1 January 2000 to 31 December 2004 was studied in a population of 313,110 inhabitants (2001 census). All patients who satisfied Poser’s criteria were considered as prevalent and incident cases.

Results: Three hundred and ninety-eight patients with MS who had experienced the clinical onset of the disease before 31 December 2004 were found in a population of 313,110 inhabitants. The prevalence rate was 127.1/100,000 [95% confidence interval (CI) 115.1–140.4]. From 2000 to 2004, 108 patients with MS had clinical onset of the disease. The mean annual incidence was 7.0/100,000 (95% CI 5.7–13.7) and was higher in women (8.4/100,000; 95% CI 6.4–10.5) than in men (5.3/100,000; 95% CI 3.7–7.2). The mean length of time between the date of clinical onset and the date of the diagnosis was 1.4 ± 1.7 years. During the last 30 years the incidence of MS in this population increased from 1.3/100,000 during the first quinquennium (1975–9) to 7.0/100,000 during 2000–4.

Conclusions: Incidence rates have further increased in this population, suggesting that the risk of MS is still increasing.

Background: Genetic and pharmacological inactivation of cannabinoid CB₁ receptors (CB₁Rs) exacerbates disease course in experimental autoimmune encephalomyelitis, suggesting that CB₁Rs might play a role in the neurodegenerative damage associated with multiple sclerosis (MS).

Objectives: To see whether CNR1 gene polymorphism could influence disease progression in relapsing–remitting MS.

Methods: The genotype of 350 patients for the number of AAT repeats was characterized and correlation studies were performed with measures of disease severity and progression.

Results: MS patients with the homozygous genotype for long AAT repeats in the CNR1 gene had more severe disease and higher risk of progression. These subjects had significantly higher scores on both the progression index and the MS severity scale. Furthermore, the percentage of patients with MS functional composite score progression or Bayesian Risk Estimate for MS (BREMS) score ≥2 (considered at very high risk of secondary progression) was significantly higher in the AAT long group than in the short group, while the frequency of patients with BREMS score ≤−0.63 (very likely to remain progression-free) was not significantly different between the two groups, although lower in the long group. Finally, the frequency of patients prescribed a second-line treatment was significantly higher among subjects of the AAT long group, providing a further, indirect indication of higher disease severity.

Conclusions: The results of the present investigation point to CB₁R as an important modulator of disease severity in relapsing MS subjects.

Background: Disability levels for patients with secondary progressive multiple sclerosis (SPMS) often worsen despite a stable MRI T₂ lesion burden. The presence of oxidative stress in the absence of measurable inflammation could help explain this phenomenon. In this study, the assessment of an in vivo marker of oxidative stress, cerebral glutathione (GSH), using magnetic resonance chemical shift imaging (CSI) is described, and GSH levels were compared in patients with SPMS and healthy controls.

Objective: To assess whether GSH, a key antioxidant in the brain, is lower in the SPMS patients compared to matched controls.

Methods: Seventeen patients with SPMS (Expanded Disability Status Scale = 4.0–7.0; length of MS diagnosis = 19.4 ± 7 years) and 17 age- and gender-matched healthy controls were studied. GSH levels were measured in the fronto-parietal regions of the brain using a specially designed magnetic resonance spectroscopy technique, CSI of GSH, at 3T.

Results: The levels of GSH were lower for SPMS patients than for controls, the largest reduction (18.5%) being in the frontal region (p = 0.001).

Conclusion: The lower GSH levels in these patients indicate the presence of oxidative stress in SPMS. This process could be at least partially responsible for ongoing functional decline in SPMS.

Background: Myelin oligodendrocyte glycoprotein (MOG) may be implicated in the immunopathogenesis of multiple sclerosis (MS) inducing demyelination in the animal model of MS. In adults reported anti-MOG antibody frequencies have been variable across a number of studies and can also be detected in controls.

Objective: To measure antibodies against MOG in paediatric patients with demyelinating disorders of the central nervous system and in controls.

Methods: Serum antibodies against MOG and myelin basic protein were measured by ELISA, flow cytometry (FACS) and in the liquid phase in 11 children with acute disseminated encephalomyelitis (ADEM), 22 children with MS, seven children with acute viral encephalitis and 13 healthy controls. The serostatus of Epstein–Barr virus (EBV) infections were assessed.

Results: Anti-MOG antibodies, measured either by ELISA or FACS were exclusively detected in children with demyelination. In ADEM these antibodies were highly reactive. Anti-MBP reactivity was detectable equally in all groups. The presence of either autoantibodies did not associate with EBV serostatus, age, gender or disease course.

Conclusions: This study independently corroborates recently published results of seroprevalence and specificity of the assay. Due to their low sensitivity anti-MOG antibodies will not serve as disease-specific biomarkers, but could help to support the diagnosis of ADEM in difficult cases.

Background: There is increasing evidence on cerebrospinal fluid (CSF) oligoclonal IgM (OCIgM) predicting a more aggressive disease course in relapsing–remitting Multiple Sclerosis (MS), while there is a scarcity of data for primary progressive MS (PPMS).

Objective: Our aim was to investigate the presence and possible prognostic value of CSF OCIgM in a group of PPMS and in a group of relapsing-onset MS patients. The possible prognostic role of other clinical and biological factors was also evaluated.

Methods: We calculated the impact of single clinical and biological factors, including CSF OCIgM at onset, on the probability of reaching an Expanded Disability Status Scale of 3 and 4 in 45 PPMS and 104 relapsing-onset MS patients.

Results: CSF OCIgM were found in only 13% of PPMS patients and did not influence the time taken to reach an Expanded Disability Status Scale of 3 and 4. Conversely, they were present in 46% of relapsing-onset MS patients and increased the risk of reaching an Expanded Disability Status Scale of 4. Clinical factors with a negative prognostic value in PPMS were age at onset <30 years and onset with pyramidal symptoms, while onset with sensory symptoms in relapsing-onset MS predicted a more favourable course.

Conclusion: This study confirms that, in relapsing-onset MS patients, the presence of CSF OCIgM at onset predicts a worse disease course. In the cohort of PPMS patients, however, CSF OCIgM were rare, suggesting that heterogeneous pathogenetic mechanisms may be involved in the different MS forms.

Objectives: To identify predictors of conversion to definite multiple sclerosis (MS) in patients with a cord clinically isolated syndrome.

Methods: The predictive values for conversion to MS of clinical, magnetic resonance imaging (MRI) and cerebrospinal fluid (CSF) variables in 114 patients with acute partial myelitis confirmed by a spinal cord lesion on MRI were studied. Other causes of cord syndromes were excluded.

Results: MS was diagnosed in 78 patients (86%) during 4.0 ± 1.9 years of follow-up. Some 67 of these patients had a second clinical episode. The diagnosis of isolated myelitis was maintained for 36 patients, 78% of whom (28 cases) were followed for at least 2 years, comparable to the MS patients. Age, bladder involvement, ≥2 cord lesions on MRI, ≥9 brain lesions, ≥3 periventricular lesions and intrathecal IgG synthesis predicted conversion to clinically definite MS. Multivariate logistic analysis identified three predictors of MS diagnosis: age ≤40 years, inflammatory CSF and ≥3 periventricular lesions on brain MRI.

Conclusion: Two out of three baseline factors (age, periventricular lesions and inflammatory CSF) predicted conversion to MS with better accuracy than the revised McDonald criteria for dissemination in space.

Background and Objectives: We evaluated clinical and conventional MRI features of a large population of patients with non-disabling MS to identify potential markers of a benign disease course.

Methods: In seven MAGNIMS centres we retrospectively identified 182 patients with benign (B) MS (EDSS score ≤3.0, disease duration ≥15 years) and 187 patients with non-disabling relapsing–remitting MS (NDRRMS) (Expanded Disability Status Scale score ≤3.0, disease duration between 5 and 14 years), in whom clinical data were collected within two weeks from a brain T2-weighted scan. Brain T2 lesion volume (LV) was measured in all patients. In 146 BMS and 146 NDRRMS patients, clinical data were also available after a median follow up of 29 months (range: 7–104 months).

Results: Mean LV was higher in BMS than in NDRRMS patients (p < 0.001), but the mean ratio between LV and disease duration was higher in NDRRMS than in BMS patients (1.1 vs. 0.6 ml/year, p < 0.001). In BMS patients, brain LV was correlated with EDSS score increase at follow up (r = 0.18, p = 0.03).

Conclusions: An overall low rate of brain LV increase during a long-lasting disease course might be a feature of BMS. In BMS patients, a high brain LV might be associated with worsening of locomotor disability at short-term follow up.

Background: Intrathecal IgM synthesis is reported to be associated with a worse prognosis in adults with multiple sclerosis (MS).

Objective: To study the predictive value of intrathecal IgM synthesis for the clinical course of pediatric MS.

Methods: Seventy children with onset of MS before the age of 16 years and followed for a median period of 10.4 years (range: 0.4–22.8 years) were studied. The two subgroups with (n = 44) or without (n = 26) intrathecal IgM synthesis were distinguished by a new, very sensitive, evaluation of quantitative analysis in cerebrospinal fluid (CSF)/serum quotient diagrams (Reibergrams). The clinical course and EDSS (Expanded Disability Status Scale) scores at five and ten years were compared with IgM frequencies between both groups with a new statistics program for CSF data.

Results: The cohort of children without intrathecal IgM production had higher numbers of attacks in the first two years and shorter time intervals between first and second attack, although this was not statistically significant (p = 0.04, p = 0.15 respectively). In addition there was also a trend for girls without intrathecal IgM synthesis to have a higher EDSS score after 10 years compared with the group with IgM synthesis.

Conclusion: Intrathecal IgM synthesis is not associated with a more rapid progression of disability in pediatric MS. Reevaluation of data from previous reports about the negative predictive value of intrathecal IgM synthesis in adult MS with a CSF statistics tool show that the apparent contradiction is due to a methodological bias in the qualitative detection of ‘oligoclonal’ IgM or linear IgM index.

Background: Levels of CXCL13, a potent B-cell chemoattractant, are elevated in the cerebrospinal fluid (CSF) during multiple sclerosis (MS) and are associated with markers of MS activity. Levels decrease upon effective treatments.

Objective: Here we validate the potential role of CSF CXCL13 as a biomarker for aspects of MS in a large amount of clinical material, the majority collected at early diagnostic work-up.

Methods: CXCL13 was measured by ELISA in 837 subjects: relapsing–remitting MS (RRMS; n = 323), secondary progressive MS (SPMS; n = 40), primary progressive MS (PPMS; n = 24), clinically isolated syndrome (CIS; n = 79), other neurological diseases (ONDs; n = 181), ONDs with signs of inflammation or viral/bacterial infections (iONDs; n = 176) and healthy controls (n = 14).

Results: Subjects with viral/bacterial infections had extremely high CXCL13 levels compared to all included groups (p < 0.0001). CXCL13 was otherwise significantly higher in MS compared to the remaining controls (p < 0.0001), and CIS (p < 0.01). A significant and positive correlation between CXCL13 and relapse rate, the results obtained for the Expanded Disability Status Scale (EDSS) and the number of lesions detected by MRI was demonstrated. CXCL13 was increased in CIS conversion to clinically definite MS (p < 0.001). Oligoclonal immunoglobulin band (OCB)-positive CIS or MS had significantly increased CXCL13 levels compared to OCB-negative CIS or MS (p < 0.001 and p < 0.0001, respectively).

Conclusion: CXCL13 was associated with disease exacerbations and unfavourable prognosis in RRMS. Increased CXCL13 was not specific for MS since subjects with viral/bacterial infections exhibited even higher levels. High levels predicted CIS conversion to MS. We suggest that measurement of CSF CXCL13 can be part of the armamentarium in the diagnostic and prognostic work-up in MS and be of help in future treatment decisions.

Background: HLA-DRB1*1501 (DR15) and other HLA class II alleles increase the risk of developing multiple sclerosis (MS). However, the contribution of genetic heterogeneity to the clinical course of MS remains controversial. We examined the influence of DR15 and other common DRB1 alleles (DRB1*01 (DR1), DRB1*03 (DR3) and DRB1*04 (DR4) on MS severity in a large, Australian, population-based cohort.

Methods: We studied the association between common HLA-DRB1 alleles and genotypes and age of onset as well as three clinical disease severity descriptors: Multiple Sclerosis Severity Score, progression index), and the interval between the first and second attack in 978 patients with relapsing remitting MS and secondary progressive MS. We assessed cognition using the Symbol Digit Modalities Test in 811 patients and brain atrophy using the linear magnetic resonance imaging marker, the intercaudate ratio, in 745 patients.

Results: Carrying DR15 significantly decreased the age of MS onset by 3.2 years in homozygotes and 1.3 years in heterozygotes. Carrying the HLA-DR15, -DR1, -DR3 or -DR4 alone or in combination did not affect clinical disease severity, cognition or cerebral atrophy.

Conclusions: This study confirms that heterogeneity of HLA-DRB1 does not influence disease outcome in relapsing MS patients, with the exception of a younger age of onset in HLA-DR15 carriers.

Background: We aimed to evaluate effects of gender on efficacy and safety of intramuscular (IM) interferon beta (IFNβ)-1a in patients with relapsing–remitting MS (RRMS) or clinically isolated syndromes (CIS) characteristic of early MS.

Methods: Pooled data from 1406 (1027 women; 379 men) patients enrolled in five clinical studies of IM IFNβ-1a were analyzed. One analysis examined data for all patients treated with IM IFNβ-1a from all studies. Separate analyses were conducted of pooled IM IFNβ-1a-treated groups from all studies and pooled IFNβ-1a-treated and placebo-treated patients from the placebo-controlled studies. Outcome measures included time to first relapse, annualized relapse rate, time to disability progression, number of gadolinium-enhanced lesions, adverse events, laboratory evaluations, and neutralizing antibodies.

Results: All efficacy assessments indicated similar treatment effects of IM IFNβ-1a in men and women with no significant treatment-by-gender interactions. Women reported more headaches, urinary tract infections, and depression in the analysis; however, these were also common in women who received placebo. Men reported more frequent flu-like symptoms in the placebo-controlled studies only. There were no other differences in the safety profile of IM IFNβ-1a between men and women.

Conclusions: We conclude that no significant gender-related differences were found in the efficacy and safety of IM IFNβ-1a in patients with RRMS or CIS.

Background: Post-marketing studies and case reports have linked beta-interferon (IFNβ) treatment with liver enzyme abnormalities and liver injuries in patients with multiple sclerosis (MS). Few predictors of risk exist.

Objective: We investigated the effect of IFNβ and other patient characteristics on levels of the liver enzyme, alanine aminotransferase (ALT).

Method: Repeated ALT test results were reviewed retrospectively for 1064 MS patients prescribed an IFNβ as their first immunomodulatory drug. Liver enzyme abnormality was defined as an ALT elevation twice the upper limit of normal (≥2 ULN). The Generalized Estimating Equation (GEE) was used to analyze the effect of age (≤35, >35–40, >40–45, >45 years), gender, disease duration, IFNβ product, and duration of treatment (≤5, >5–15, >15–40, >40 months) on de novo liver enzyme abnormality.

Results: Over a mean treatment period of 38.7 months (SD = 34.9), 12.4% (95/766) of MS patients developed de novo liver enzyme abnormality. Multivariable GEE results showed a dose frequency response effect of IFNβs on liver enzyme abnormality: OR = 3.8(95% CI: 1.6–9.2) for IFNβ-1a 44 µg SC, and OR = 3.4 (95% CI: 1.5–7.9) for IFNβ-1b 250 µg SC compared with the lower frequency IFNβ-1a 30 µg IM. Younger age (≤40 years), male gender, and ≤15 months of IFNβ exposure were also independent predictors.

Conclusion: A dose frequency response effect was observed, with high-frequency IFNβs having the greatest risk. The first 15 months of treatment, men, and younger patients were also associated with elevated risk. Regular ALT monitoring in MS patients appears prudent; long-term consequences of ALT elevations should be further investigated.

Natalizumab is a monoclonal antibody shown to be highly effective in the treatment of relapsing–remitting multiple sclerosis (RRMS). Patients treated with natalizumab can develop antibodies directed against this agent that may affect the efficacy and safety of the drug. In this observational study, the kinetics of the appearance and the incidence of anti-natalizumab antibodies were followed prospectively for 18 months in a cohort of 64 consecutive patients treated with natalizumab for relapsing MS. Blood samples were drawn immediately before starting natalizumab therapy and each month afterwards. The presence of antibodies against natalizumab was assessed by enzyme-linked immunosorbent assay (ELISA) in all patients. Anti-natalizumab antibodies were detected in nine (14.1%) natalizumab-treated patients, three (4.68%) of whom were transiently positive while six (9.37%) were persistently positive (these patients discontinued natalizumab). All positive titres were observed during the first 4 months of treatment. One patient with a hypersensitivity reaction also had persistent antibodies. We conclude that antibodies against natalizumab develop early, within the first 6 months of therapy with natalizumab. Although no antibodies were detected after 4 months of therapy in this particular study, this does not rule out their development later on in exceptional cases.

In this prospective post-marketing study, 21 patients with multiple sclerosis treated with natalizumab for 24 consecutive months elected a trial of treatment interruption (90–180 days). During a mean duration of treatment interruption of 111.5 days 4 patients (19.0%) experienced a relapse and 9 out of 19 (47.4%) had MRI activity. Number of contrast-enhancing lesions at baseline was lower than during treatment interruption, but the difference was not significant. These findings suggest that disease activity may return after the last infusion of natalizumab. Patients should have regular MRI assessment during treatment interruption to rapidly identify any return of disease activity. The aim of this study was to determine the optimal duration for temporary interruption of natalizumab therapy in patients who have received continuous therapy with natalizumab for 24 months.