Immunosenescence and vaccine efficacy revealed by immunometabolic analysis of SARS-CoV-2-specific cells in multiple sclerosis patients

Disease-modifying therapies (DMT) administered to patients with multiple sclerosis (MS) can influence immune responses to SARS-CoV-2 and vaccine efficacy. However, data on the detailed phenotypic, functional and metabolic characteristics of antigen (Ag)-specific cells following the third dose of mRNA vaccine remain scarce. Here, using flow cytometry and 45-parameter mass cytometry, we broadly investigate the phenotype, function and the single-cell metabolic profile of SARS-CoV-2-specific T and B cells up to 8 months after the third dose of mRNA vaccine in a cohort of 94 patients with MS treated with different DMT, including cladribine, dimethyl fumarate, fingolimod, interferon, natalizumab, teriflunomide, rituximab or ocrelizumab. Almost all patients display functional immune response to SARS-CoV-2. Different metabolic profiles characterize antigen-specific-T and -B cell response in fingolimod- and natalizumab-treated patients, whose immune response differs from all the other MS treatments.

Clinical relevance of thymic and bone marrow outputs in multiple sclerosis patients treated with alemtuzumab

Thymic and bone marrow outputs were evaluated in 13 sequential samples of 68 multiple sclerosis patients who initiated alemtuzumab and were clinically followed for 48 months. Three months after alemtuzumab infusions, the levels of new T lymphocytes were significantly reduced, but progressively increased reaching the highest values at 36 months, indicating the remarkable capacity of thymic function recovery. Newly produced B cells exceeded baseline levels as early as 3 months after alemtuzumab initiation. Heterogeneous patterns of new T- and B-cell recovery were identified, but without associations with age, sex, previous therapies, development of secondary autoimmunity or infections, and disease re-emergence. Trial registration version 2.0-27/01/2016.

The impact of PM2.5, PM10 and NO2 on Covid-19 severity in a sample of patients with multiple sclerosis: A case-control study

BACKGROUND

Many studies investigated the association between air pollution and Covid-19 severity but the only study focusing on patients with Multiple Sclerosis (MS) exclusively evaluated exposure to PM2.5. We aim to study, in a sample of MS patients, the impact of long-term exposure to PM2.5, PM10 and NO2 on Covid-19 severity, described as occurrence of pneumonia.

METHODS

A 1:2 ratio case-control study was designed, differentiating cases and controls based on Covid-19 pneumonia. Associations between pollutants and outcome were studied using logistic regression. Weighted quantile sum (WQS) logistic regression was used to identify the individual contribution of each pollutant within the mixture; Least Absolute Shrinkage and Selection Operator (LASSO) penalized regression was performed to confirm the variable selection from WQS. All the analyses were adjusted for confounders selected a priori.

RESULTS

Of the 615 eligible patients, 491 patients provided detailed place of exposure and were included in the principal analysis. Higher concentrations of air pollutants were associated with increased odds of developing Covid-19 pneumonia (PM2.5: 3rd vs 1st tercile OR(95% CI)=2.26(1.29;3.96); PM10: 3rd vs 1st tercile OR(95% CI)=2.12(1.22;3.68); NO2: 3rd vs 1st tercile OR(95% CI)=2.12(1.21;3.69)). Pollutants were highly correlated with each other; WQS index was associated to an increased risk of pneumonia (β=0.44; p-value=0.004) and the main contributors to this association were NO2 (41%) and PM2.5 (34%). Consistently, Lasso method selected PM2.5 and NO2.

CONCLUSIONS

Higher long-term exposure to PM2.5, PM10 and NO2 increased the odds of Covid-19 pneumonia among MS patients and the most dangerous pollutants were NO2 and PM2.5.

Exposure to natalizumab throughout pregnancy: effectiveness and safety in an Italian cohort of women with multiple sclerosis

OBJECTIVE

Assessing the risk of clinical and radiological reactivation during pregnancy and post partum in women with multiple sclerosis (MS) treated with natalizumab (NTZ) throughout pregnancy (LONG_EXP) compared with women interrupting treatment before (NO_EXP) and within >-30 days and ≤90 days from conception (SHORT_EXP), and describing newborns' outcomes.

METHODS

Maternal clinical and radiological outcomes and obstetric and fetal outcomes were retrospectively collected and compared among groups (NO_EXP, SHORT_EXP, LONG_EXP). Predictors of clinical and radiological reactivation were investigated through univariable and multivariable analysis.

RESULTS

170 eligible pregnancies from 163 women referring to 29 Italian MS centres were included. Annualised relapse rate (ARR) was significantly lower in LONG_EXP (n=66, 0.02 (0.001-0.09)) compared with NO_EXP (n=31, 0.43 (0.21-0.75), p=0.002) and SHORT_EXP (n=73, 0.46 (0.30-0.66), p=0.0004) during pregnancy, and in LONG_EXP (0.12 (0.05-0.24)) compared with SHORT_EXP (0.30 (0.17-0.50), p=0.008) during post partum. Gadolinium-enhancing (Gd+) lesions were less frequent in LONG_EXP (n=6/50, 2.00%) compared with NO_EXP (n=9/21, 42.86%) and SHORT_EXP after delivery (n=17/49, 34.69%, p=0.010).Delaying NTZ resumption after delivery significantly increased the risk of relapses (OR=1.29 (95% CI 1.07 to 1.57), p=0.009) and Gd+ lesions (OR=1.49 (95% CI 1.17 to 1.89, p=0.001). Newborns' weight, length, head circumference and gestational age did not differ among groups after adjusting for confounders. Anaemia was tracked in 4/69 LONG_EXP newborns. Congenital anomaly rate was within the expected range for the untreated MS population.

CONCLUSIONS

Our findings indicate that in women with MS treated with NTZ before conception, continuation of NTZ throughout pregnancy and its early resumption after delivery mitigate the risk of clinical and radiological reactivation. This approach has no major impact on newborns' outcomes.

Inter-Laboratory Concordance of Cerebrospinal Fluid and Serum Kappa Free Light Chain Measurements

The kappa index (K-Index), calculated by dividing the cerebrospinal fluid (CSF)/serum kappa free light chain (KFLC) ratio by the CSF/serum albumin ratio, is gaining increasing interest as a marker of intrathecal immunoglobulin synthesis. However, data on inter-laboratory agreement of these measures is lacking. The aim was to assess the concordance of CSF and serum KFLC measurements, and of K-index values, across different laboratories. KFLC and albumin of 15 paired CSF and serum samples were analyzed by eight participating laboratories. Four centers used Binding Site instruments and assays (B), three used Siemens instruments and assays (S), and one center used a Siemens instrument with a Binding Site assay (mixed). Absolute individual agreement was calculated using a two-way mixed effects intraclass correlation coefficient (ICC). Cohen’s kappa coefficient (k) was used to measure agreement on positive (≥5.8) K-index values. There was an excellent agreement in CSF KFLC measurements across all laboratories (ICC (95% confidence interval): 0.93 (0.87–0.97)) and of serum KFLC across B and S laboratories (ICC: 0.91 (0.73–0.97)), while ICC decreased (to 0.81 (0.53–0.93)) when including the mixed laboratory in the analysis. Concordance for a positive K-Index was substantial across all laboratories (k = 0.77) and within S laboratories (k = 0.71), and very good (k = 0.89) within B laboratories, meaning that patients rarely get discordant results on K-index positivity notwithstanding the testing in different laboratories and the use of different platforms/assays.

Risk of multiple sclerosis relapses when switching from fingolimod to cell-depleting agents: the role of washout duration

BACKGROUND

Fingolimod (FTY) induces sequestration of lymphocytes in secondary lymphoid organs and the average lymphocyte recovery following discontinuation takes 1-2 months. It has been hypothesized that the therapeutic effects of subsequent cell-depleting agents may be compromised if initiated before lymphocyte recovery has occurred.

OBJECTIVE

To assess the risk of relapses following FTY discontinuation and the initiation of a B/T cell-depleting agent in relation to washout duration using data from the Italian MS Register.

METHODS

The risk of relapses was assessed in relation to different washout durations (< 6, 6-11, 12-17 and > / = 18 weeks) in patients starting alemtuzumab, rituximab, ocrelizumab or cladribine following FTY discontinuation.

RESULTS

We included 329 patients in the analysis (226F, 103 M; mean age 41 ± 10 years). During the cell-depleting treatment, the incidence rate ratio for a relapse was significantly greater in patients with a washout period of 12-17 and > / = 18 weeks compared to the reference period (< 6 weeks). The risk of a relapse was significantly influenced by the occurrence of relapses during FTY treatment and by washout length, with hazard ratios markedly increasing with the washout duration.

CONCLUSION

The risk of relapses increases with the washout duration when switching from FTY to lymphocyte-depleting agents.

Antibiotic Use and Risk of Multiple Sclerosis: A Nested Case-Control Study in Emilia-Romagna Region, Italy

INTRODUCTION

Known risk factors for multiple sclerosis (MS) include smoking, a low vitamin D status, obesity, and EBV, while the inflammatory feature of the disease strongly suggests the presence of additional infectious agents. The association between use of antibiotics and MS risk that could shed light on these factors is still undetermined. We aimed to evaluate the association between antibiotics and MS risk, in the Emilia-Romagna region (RER), Italy.

METHODS

All adult patients with MS seen at any RER MS center (2015-2017) were eligible. For each of the 877 patients included, clinical information was collected and matched to 5 controls (RER residents) (n = 4,205) based on age, sex, place of residence, and index year. Information on antibiotic prescription was obtained through the linkage with the RER drug prescription database.

RESULTS

Exposure to any antibiotic 3 years prior to the index year was associated with an increased MS risk (OR = 1.52; 95% CI = 1.29-1.79). Similar results were found for different classes. No dose-response effect was found.

DISCUSSION/CONCLUSIONS

Our results suggest an association between the use of antibiotics and MS risk in RER population. However, further epidemiological studies should be done with information on early life and lifestyle factors.

Kappa Index Versus CSF Oligoclonal Bands in Predicting Multiple Sclerosis and Infectious/Inflammatory CNS Disorders

Background: Cerebrospinal fluid (CSF) kappa free light chains (KFLC) are gaining increasing interest as markers of intrathecal immunoglobulin synthesis. The main aim of this study was to assess the diagnostic accuracy (AUC) of the kappa index (CSF/serum KFLC divided by the CSF/serum albumin ratio) compared to CSF oligoclonal IgG bands (OCB) in predicting Multiple Sclerosis (MS) or a central nervous system infectious/inflammatory disorder (CNSID). Methods: We enrolled patients who underwent a diagnostic spinal tap throughout two years. KFLC levels were determined using a Freelite assay (Binding Site) and the turbidimetric Optilite analyzer. Results: Of 540 included patients, 223 had a CNSID, and 84 had MS. The kappa index was more sensitive (0.89 versus 0.85) and less specific (0.84 versus 0.89), with the same AUC (0.87) as OCB for MS diagnosis (optimal cut-off: 6.2). Adding patients with a single CSF IgG band to the OCB-positive group slightly increased the AUC (0.88). Likewise, the kappa index (cut-off: 3.9) was more sensitive (0.67 versus 0.50) and less specific (0.81 versus 0.97), with the same AUC (0.74) as OCB, for a CNSID diagnosis. Conclusion: The kappa index and CSF OCB have comparable diagnostic accuracies for a MS or CNSID diagnosis and supply the clinician with useful, complementary information.

Dimethyl fumarate-induced lymphocyte count drop is related to clinical effectiveness in relapsing-remitting multiple sclerosis

BACKGROUND AND PURPOSE

Dimethyl fumarate (DMF) causes a mean lymphocyte count drop of approximately 30% in relapsing-remitting multiple sclerosis (RRMS) patients. The relationship between this reduction and DMF effectiveness is controversial. The objective was to investigate if the decrease in absolute lymphocyte count (ALC) from baseline during DMF treatment is associated with clinical and magnetic resonance imaging (MRI) disease activity. A secondary aim was to evaluate ALC variations over time in a real-life cohort of DMF-treated patients.

METHODS

Demographic, laboratory, clinical and MRI data were collected in this observational multicentre study, conducted on RRMS patients treated with DMF for at least 6 months. Multivariate Cox models were performed to evaluate the impact of 6-month ALC drop on time to no evidence of disease activity (NEDA-3) status loss. NEDA-3 is defined as absence of clinical relapses, MRI disease activity and confirmed disability progression.

RESULTS

In all, 476 patients (312 females, age at DMF start 38.4 ± 9.97 years) were analysed up to 5-year follow-up. A greater lymphocyte decrease was associated with a lower risk of NEDA-3 status loss (hazard ratio 0.87, P = 0.01). A worse outcome in patients with lower ALC drop (<11.5%), compared with higher tertiles (11.5%-40.5% and >40.5%), was observed (P = 0.008). The nadir of ALC drop (-33.6%) and 35% of grade III lymphopaenia cases occurred after 12 months of treatment.

CONCLUSION

A higher lymphocyte count drop at 6 months is related to better outcomes in DMF-treated patients. A careful ALC monitoring should be pursued up to 24 months of treatment.

A voxel-based lesion symptom mapping analysis of chronic pain in multiple sclerosis

BACKGROUND

Pain is one of the most disabling symptoms in multiple sclerosis. Chronic pain in multiple sclerosis is often neuropathic in nature, although a clear-cut distinction with nociceptive pain is not easy.

OBJECTIVE

The aim of our study was to analyze the MRIs of multiple sclerosis patients with chronic pain in order to explore possible associations with lesion sites, on a voxel-by-voxel basis.

MATERIALS AND METHODS

We enrolled patients aged > 18 years with multiple sclerosis in accordance with the 2010 McDonald criteria. Patients meeting criteria for persistent pain (frequent or constant pain lasting > 3 months) were included in the "pain group". The other patients were included in the "no pain group". We outlined lesions on FLAIR MRI scans using a semi-automated edge finding tool. To detect the association between lesion localization and persistent pain, images were analysed with the voxel-based lesion symptom mapping methods implemented in the (nonparametric mapping software included into the MRIcron.

RESULTS

We enrolled 208 MS patients (140 F, mean age 55.2 ± 9.4 years; 176 RR, 28 progressive MS; mean EDSS 2.0 + 2.0). Pain group included 96 patients and no pain group 112 patients. Lesions of the right dorsolateral prefrontal area were significantly more prevalent in patients without pain, whereas periventricular posterior lesions were significantly more prevalent in patients with persistent pain.

CONCLUSION

Our data suggest a role of the right dorsolateral prefrontal cortex in the modulation of pain perception and in the occurrence of chronic pain in MS patients. Our data also support a hemispheric asymmetry in pain perception and modulation.

Mitochondrial damage-associated molecular patterns stimulate reactive oxygen species production in human microglia

Microglia are the resident innate immune cells of the central nervous system and exert functions of host defense and maintenance of normal tissue homeostasis, along with support of neuronal processes in the healthy brain. Chronic and dysregulated microglial cell activation has increasingly been linked to the status of neuroinflammation underlying many neurodegenerative diseases, including multiple sclerosis (MS). However, the stimulus (or stimuli) and mechanisms by which microglial activation is initiated and maintained MS are still debated. The purpose of our research was to investigate whether the endogenous mitochondrial (mt)-derived damage-associated molecular patterns (MTDs) mtDNA, N-formyl peptides and cardiolipin (CL) contribute to these phenomena. We characterized the effects of the abovementioned MTDs on microglia activation in vitro (i.e. using HMC3 cells) by evaluating the expression of gene coding for proteins involved in their binding and coupled to downstream signaling pathways, the up-regulation of markers of activation on the cell surface and the production of pro-inflammatory cytokines and reactive oxygen species. At the transcriptional level, significant variations in the mRNA relative expression of five of eleven selected genes were observed in response to stimulation. No changes in activation of antigenic profile or functional properties of HMC3 cells were observed; there was no up-regulation of HLA-DR expression or increased secretion of tumor necrosis factor-α and interleukin-6. However, after stimulation with mtDNA and CL, an increase in cellular oxidative stress, but not in the mt ROS O₂^-, compared to control cells, were observed. There were no effects on cell viability. Overall, our data suggest that MTDs could cause a failure in microglial activation toward a pro-inflammatory phenotype, possibly triggering an endogenous regulatory mechanism for the resolution of neuroinflammation. This could open a door for the development of drugs selectively targeting microglia and modulating its functionality to treat MS and/or other neurodegenerative conditions in which MTDs have a pathogenic relevance.

Plasma neurofilaments correlate with disability in progressive multiple sclerosis patients

OBJECTIVES

Cerebrospinal fluid (CSF) and blood neurofilaments (NFLs) are markers of axonal damage and are being investigated, mostly in relapsing-remitting (RR) MS, as a marker of disease activity and of response to treatment, while there are less data in progressive MS patients. Primary aim was to measure NFL in plasma samples of untreated patients with primary (PP) and secondary (SP) progressive MS and to correlate them with disability, disease severity, and prior/subsequent disability progression.

MATERIALS AND METHODS

Neurofilament concentrations were measured using SIMOA (Single Molecule Array, Simoa HD-1 Analyzer; Quanterix).

RESULTS

Neurofilament concentrations were measured on plasma samples of 70 progressive (27 PP and 43 SP), 21 RRMS patients, and 10 HCs. Longitudinal plasma NFL (pNFL) concentrations (median interval between sampling: 25 months) were available for nine PP/SP patients. PNFL concentrations were significantly higher in PP/SP compared to RRMS patients. They correlated with EDSS and MS Severity Score values. There was no difference in pNFL levels between PP/SP patients with EDSS progression in the preceding year (14% of patients) or during a median follow-up of 27 months (41%). In the longitudinal sub-study, pNFL levels increased in all patients between sampling by a mean value of 23% while EDSS mostly remained stable (77% of cases).

CONCLUSION

In PP/SP progressive MS patients, pNFL levels correlate with disability and increase over time, but are not associated with prior/subsequent disability progression, as measured by EDSS, which may not be a sufficiently sensitive tool in this context.

Mitochondrial functionality and metabolism in T cells from progressive multiple sclerosis patients

Patients with primary progressive (PP) and secondary progressive (SP) forms of multiple sclerosis (MS) exhibit a sustained increase in the number of Th1, T cytotoxic type-1 and Th17 cells in peripheral blood, suggesting that the progressive phase is characterized by a permanent peripheral immune activation. As T cell functionality and activation are strictly connected to their metabolic profile, we investigated the mitochondrial functionality and metabolic changes of T cell subpopulations in a cohort of progressive MS patients. T cells from progressive patients were characterized by low proliferation and increase of terminally differentiated/exhausted cells. T cells from PP patients showed lower Oxygen Consumption Rate and Extracellular Acidification Rate, lower mitochondrial mass, membrane potential and respiration than those of SP patients, a downregulation of transcription factors supporting respiration and higher tendency to shift towards glycolysis upon stimulation. Furthermore, PP effector memory T cells were characterized by higher Glucose transporter -1 levels and a higher expression of glycolytic-supporting genes if compared to SP patients. Overall, our data suggest that profound differences exist in the phenotypic and metabolic features of T cells from PP and SP patients, even though the two clinical phenotypes are considered part of the same disease spectrum.

Clinical, laboratory features, and prognostic factors in adult acute transverse myelitis: an Italian multicenter study

OBJECTIVES

We compared the clinical, laboratory, and radiological features of different subgroups of acute transverse myelitis (ATM) diagnosed according to the criteria established by the Transverse Myelitis Consortium Working Group (TMCWG) as well as of non-inflammatory acute transverse myelopathies (NIATM) to identify possible short- and long-term prognostic factors.

METHODS

A multicenter and retrospective study comprising 110 patients with ATM and 15 NIATM admitted to five Italian neurological units between January 2010 and December 2014 was carried out.

RESULTS

A significantly higher frequency of isolated sensory disturbances at onset in ATM than in NIATM patients (chi-square = 14. 7; P = 0.005) and a significantly higher frequency of motor symptoms in NIATM than ATM (chi-square = 12.4; P = 0.014) was found. ATM patients with high disability at discharge had more motor-sensory symptoms without (OR = 3.87; P = 0.04) and with sphincter dysfunction at onset (OR = 7.4; P = 0.0009) compared to those with low disability. Higher age (OR = 1.08; P = 0.001) and motor-sensory-sphincter involvement at onset (OR = 9.52; P = 0.002) were significantly associated with a high disability score at discharge and after a median 1-year follow-up.

CONCLUSIONS

The diagnosis of ATM may prevail respect to that of NIATM when a sensory symptomatology at onset occurs. In ATM, patients older and with motor-sensory involvement with or without sphincter impairment at admission could experience a major risk of poor prognosis both at discharge and at longer time requiring a timely and more appropriate treatment.

First-line disease-modifying drugs in relapsing-remitting multiple sclerosis: an Italian real-life multicenter study on persistence

OBJECTIVE

The introduction of oral disease-modifying drugs (DMDs) in addition to the available, injectable, ones for relapsing-remitting multiple sclerosis (RRMS) could be expected to improve medication persistence due to a greater acceptability of the route of administration. The aim of the study was to compare the proportion of patients discontinuing injectable DMDs (interferon beta 1a/1b, pegylated interferon, glatiramer acetate) with those discontinuing oral DMDs (dimethylfumarate and teriflunomide) during an observation period of at least 12 months. Secondary aims were to compare the time to discontinuation and the reasons for discontinuation between the two groups and to explore the demographic and clinical factors associated with DMD discontinuation.

METHODS

In this prospective, multi-center, real-life observational study, patients commencing any first-line DMD between 1 January 2015 and 31 July 2016 were enrolled and followed up for at least 12 months or until the drug was discontinued.

RESULTS

Of the 520 included patients, 262 (49.6%) started an injectable and 258 (50.4%) an oral DMD. There was no difference in the proportion of patients on oral (n = 62, 24%) or on injectable (n = 60, 23%) DMDs discontinuing treatment, the most frequent reason being adverse events/side-effects. Higher baseline Expanded Disability Status Scale (EDSS) scores and younger age increased the odds of treatment withdrawal. Time to treatment discontinuation was not different between the two groups and was not influenced by the initiated DMD (oral versus injectable), even after adjustment for baseline differences.

CONCLUSION

The route of administration alone (i.e. oral versus injectable) was not a significant predictor of persistence with first-line DMDs in RRMS.

iNKT Cells in Secondary Progressive Multiple Sclerosis Patients Display Pro-inflammatory Profiles

BACKGROUND

Multiple sclerosis (MS), an autoimmune disease with neurodegeneration and inflammation is characterized by several alterations of different T cell subsets. However, few data exist on the role of iNKT lymphocytes.

OBJECTIVE

To identify possible changes in the phenotype of iNKT cells in patients with different clinical forms of MS and find alterations in their polyfunctionality [i.e., ability to produce simultaneously up to four cytokines such as IL-17, tumor necrosis factor (TNF)-α, interferon (IFN)-γ, and IL-4].

METHODS

We studied a total of 165 patients, 91 with a relapsing-remitting form [RR; 31 were treated with interferon (IFN)1a-β, 25 with natalizumab (NAT), 29 with glatiramer acetate; 17 were newly diagnosed RR without treatment, 19 not-active RR without treatment]. Forty-four patients had a progressive MS: 20 primary progressive (PP) and 24 secondary progressive (SP). A total of 55 age- and sex-matched subjects represented healthy controls (CTR). Among fresh peripheral blood mononuclear cells, iNKT cells were identified by flow cytometry. Moreover, the capability of iNKT cells to produce different cytokines (IL-17, TNF-α, IFN-γ, and IL-4) after in vitro stimulation were evaluated in 18 RR (11 treated with NAT and 7 with IFN), 4 PP, 6 SP, and 16 CTR.

RESULTS

No main differences were found in iNKT cell phenotype among MS patients with different MS forms or during different treatments. However, the polyfunctional response of iNKT cells showed Th1 and Th17 profiles. This was well evident in patients with SP form, who are characterized by high levels of inflammation and neurodegeneration, and exhibited a sustained increase in the production of Th17 cytokines. Patients treated with NAT displayed lower levels of iNKT cells producing IL-17, TNF-α, and IFN-γ.

CONCLUSION

Our data suggest that the progressive phase of the disease is characterized by permanent iNKT activation and a skewing towards an inflammatory phenotype. Compared to other treatments, NAT was able to modulate iNKT cell function.

Novel outcome measures for Charcot-Marie-Tooth disease: validation and reliability of the 6-min walk test and StepWatch(™) Activity Monitor and identification of the walking features related to higher quality of life

BACKGROUND AND PURPOSE

Charcot-Marie-Tooth (CMT) disease is the most common inherited neuropathy, but therapeutic options have been limited to symptom management. Past pharmacological trials have failed, possibly due to insensitive outcome measures (OMs). The aim of the current study was to evaluate the validity and reliability of the 6-min walk test (6MWT) and StepWatch(™) Activity Monitoring (SAM) with other previously validated OMs in CMT disease.

METHODS

A prospective multicenter study was performed, consecutively enrolling 168 CMT patients (104 with CMT1A, 27 with CMT1B, 37 with X-linked CMT) from Italian centers specializing in CMT care.

RESULTS

Statistical analysis showed that the 6MWT was highly related with all previously used OMs. Some, but not all, SAM parameters were related to commonly used OMs but may provide more information about quality of life.

CONCLUSIONS

The current study demonstrated the validity and reliability of the 6MWT and SAM as OMs for CMT. Moreover, SAM provides data that correlate better with quality of life measures, making it useful in future rehabilitation trials.

Cerebrospinal fluid amounts of HLA-G in dimeric form are strongly associated to patients with MRI inactive multiple sclerosis

Background:

The relevance of human leukocyte antigen (HLA)-G in dimeric form in multiple sclerosis (MS) is still unknown.

Objective:

To investigate the contribution of cerebrospinal fluid (CSF) HLA-G dimers in MS pathogenesis.

Methods:

CSF amounts of 78-kDa HLA-G dimers were measured by western blot analysis in 80 MS relapsing–remitting MS (RRMS) patients and in 81 inflammatory and 70 non-inflammatory controls.

Results:

CSF amounts of 78kDa HLA-G dimers were more frequent in RRMS than in inflammatory ( p<0.01) and non-inflammatory controls ( p<0.001) and in magnetic resonance imaging (MRI) inactive than in MRI active RRMS ( p<0.00001).

Conclusion:

Our findings suggest that HLA-G dimers may be implicated in termination of inflammatory response occurring in MS.

Cerebrospinal fluid CXCL13 in clinically isolated syndrome patients: Association with oligoclonal IgM bands and prediction of Multiple Sclerosis diagnosis

Cerebrospinal fluid (CSF) CXCL13 was shown to correlate with markers of intrathecal inflammation and CSF oligoclonal IgM bands (IgMOB) have been associated with a more severe Multiple Sclerosis (MS) course. We correlated CSF CXCL13 levels with clinical, MRI and CSF parameters, including CSF IgMOB, in 110 Clinically Isolated Syndrome (CIS) patients. CSF CXCL13 levels correlated with CSF cell count, total protein, IgG Index and with the presence of CSF IgGOB and IgMOB. CSF CXCL13 levels ≥15.4 pg/ml showed a good positive predictive value and specificity for a MS diagnosis and for a clinical relapse within one year from onset.

Treatment of relapsing-remitting multiple sclerosis after 24 doses of natalizumab: evidence from an Italian spontaneous, prospective, and observational study (the TY-STOP Study)

IMPORTANCE

The evaluation of therapeutic choices is needed after 24 doses of natalizumab in patients with multiple sclerosis (MS).

OBJECTIVE

To evaluate the effect of therapeutic choices on the mean annualized relapse rate and on magnetic resonance imaging MS activity after 24 doses of natalizumab in patients with relapsing-remitting MS.

DESIGN, SETTING, AND PARTICIPANTS

The TY-STOP study, which recruited participants between October 22, 2010, and October 22, 2012, at 8 Italian MS centers (secondary care outpatient clinics) among 124 adult patients who demonstrated no clinical or magnetic resonance imaging MS activity after 24 doses of natalizumab.

INTERVENTIONS

Natalizumab, no treatment, interferon beta, glatiramer acetate, or fingolimod.

MAIN OUTCOMES AND MEASURES

The primary end point was the mean annualized relapse rate. Statistical analyses were performed in 124 patients with complete follow-up data among 130 patients who were recruited and stratified into study groups. In the intent-to-treat group, the decision was made to continue or interrupt natalizumab after 24 doses. In the as-treated group, natalizumab continuers received natalizumab, natalizumab switchers changed to different therapies, and natalizumab quitters discontinued natalizumab during the study year.

RESULTS

No significant differences in demographic or baseline clinical characteristics were found among the study participants. In the intent-to-treat group (n = 124), clinical (P = .004) and radiologic (P = .02) MS activity was significantly lower in patients continuing natalizumab (n = 43) than in patients interrupting natalizumab (n = 81), with a protective effect of natalizumab continuation on both outcomes (odds ratio [OR], 0.33; 95% CI, 0.15-0.70 for clinical activity and OR, 0.35; 95% CI, 0.15-0.79 for radiologic activity). In the as-treated group (n = 124), clinical (P = .003) and radiologic (P = .03) MS activity was significantly lower in natalizumab continuers than in natalizumab switchers or quitters, confirming a protective effect of natalizumab on the risk of relapse in natalizumab continuers compared with natalizumab quitters (OR, 4.40; 95% CI, 1.72-11.23) and natalizumab switchers (OR, 3.28; 95% CI, 0.99-10.79). No disease rebound was observed in natalizumab quitters. After natalizumab discontinuation, 1 patient developed progressive multifocal leukoencephalopathy during the observation period, with complete recovery.

CONCLUSIONS AND RELEVANCE

This study provides class III evidence of an increased risk of MS activity resumption after natalizumab discontinuation. Therapy discontinuation after 24 doses in natalizumab-responding patients should be considered only if the risk of progressive multifocal leukoencephalopathy is high and outweighs the benefits of continuing the drug.

TRIAL REGISTRATION

Osservatorio Nazionale Sulla Sperimentazione Clinica dei Medicinali No. 131/2010.

Previous treatment influences fingolimod efficacy in relapsing-remitting multiple sclerosis: results from an observational study

OBJECTIVE

Fingolimod (FTY) is licensed as a disease-modifying treatment in highly active relapsing-remitting multiple sclerosis. The aim of the study was to evaluate the efficacy and safety of FTY in a real-life setting and to explore the possible role of clinical and MRI parameters, including previous treatment type, in predicting its efficacy.

METHODS

Clinical and MRI data was collected on 127 patients assigned to treatment with FTY in six multiple sclerosis centers in Emilia-Romagna, Italy, between August 2011 and June 2013.

RESULTS

During a mean follow-up period of 10 months (range 1-22), we observed a total of 47 relapses in 39 patients (30.7%); new T2 lesions or gadolinium-enhancing (Gd+) lesions were present at follow-up MRI in 32/71 patients (45%). Expanded disability status scale (EDSS) at the end of the follow-up period was not different when compared to the baseline EDSS. Serious adverse events occurred in three patients (2.4%). A higher proportion of patients previously treated with natalizumab showed clinical (41%) or MRI activity (54%). Previous treatment with natalizumab increased the risk of a relapse within 30 days (versus immunomodulatory drugs; OR: 4.3; p = 0.011) and at survival analysis (versus remaining patients; HR: 1.9; p = 0.046). Study limitations include a small population sample, a short observation period with variable timing of follow-up MRI and different baseline characteristics of patients previously treated with natalizumab compared to those treated with immunomodulatory drugs.

CONCLUSIONS

This study confirms the efficacy of FTY in reducing relapse rate in patients previously treated with immunomodulatory drugs, while it seems to be less effective in patients discontinuing natalizumab. Due to the short duration of follow-up it is not possible to evaluate disability progression; however, no difference was observed between the groups.

Non-length-dependent small fibre neuropathy. Confocal microscopy study of the corneal innervation

BACKGROUND

It has been recently observed that small fibre neuropathy (SFN) may present as distal symmetrical polyneuropathy and with atypical non-length-dependent pattern.

OBJECTIVE

To describe a small series of patients with non-length-dependent SFN, investigating corneal innervation with corneal confocal microscopy (CCM).

METHODS

Evaluation of the corneal nerve fibre density using CCM in six women with non-length-dependent SFN. The patients were characterised by sensory disturbance involving proximal regions of the limbs, face and trunks, and the diagnosis was confirmed by the findings of decreased intraepidermal nerve fibre density on skin biopsy.

RESULTS

Six women, aged 35-64, had non-length-dependent SFN, related to Crohn disease, impaired glucose tolerance and Sjögren's syndrome, or idiopathic (three cases). In all patients, CCM demonstrated decreased corneal nerve fibre density (12.5-23.4/mm(2); normal, >30.6/mm(2)).

CONCLUSION

Non-length-dependent SFN may represent an intriguing diagnostic problem because of its puzzling presentation and the need for special investigations for its confirmation. In this perspective, CCM may provide a useful, non-invasive tool to complement the diagnostic workup.

Restless legs syndrome and painful neuropathy-retrospective study. A role for nociceptive deafferentation?

OBJECTIVES

Restless legs syndrome (RLS) occurs in polyneuropathy with small fiber involvement, possibly as a peculiar form of neuropathic pain; however, the relationship between pain and RLS has been poorly investigated in polyneuropathy.

DESIGN, SETTING, AND PATIENTS

We evaluated retrospectively the occurrence of RLS in 102 consecutive patients with polyneuropathy manifesting with neuropathic pain or dysesthesia, referred to the Neuromuscular Center, using the National Institutes of Health criteria for RLS. The patients were classified in subgroups characterized respectively by allodynia (hyperphenomena), with reported unpleasant sensations evoked by tactile stimuli, and hypoalgesia (hypophenomena), with absent pain sensation to pinprick, according to putative mechanisms of pain.

RESULTS

RLS was present in 41/102 patients (40.2%). It was significantly more frequent in the "hypoalgesia" (23/37) than in the "allodynia" subgroup (9/31; P = 0.008) and in the not classifiable cases (9/34; P = 0.004).

CONCLUSIONS

RLS is frequent in painful polyneuropathy and is significantly associated with decreased small fiber input, thus nociceptive deafferentation may represent a factor interacting with RLS "generators," possibly at spinal level. We suggest that overactivity of the spinal structures implicated in RLS may be triggered by nociceptive deafferentation in a subgroup of patients with painful polyneuropathy. Our findings, prompting a mechanistic characterization of RLS associated with painful polyneuropathy, have to be confirmed in a prospective study.

Restless legs syndrome: differential diagnosis and management with pramipexole

Restless legs syndrome (RLS) is a condition characterized by discomfort at rest and urge to move focused on the legs. RLS may occur as an idiopathic, often hereditary condition (primary RLS), or in association with medical conditions (secondary RLS) including iron deficiency, uremia, and polyneuropathy. Current understanding of the pathophysiology of RLS points to the involvement of three interrelated components: dopaminergic dysfunction, impaired iron homeostasis, and genetic mechanisms. The diagnosis of RLS is made according to the consensus criteria by a National Institutes of Health panel: 1) an urge to move the legs, usually accompanied by uncomfortable sensations; 2) beginning or worsening during rest; 3) relieved by movement; and 4) worse, or only occurring, in the evening or at night. The differential diagnosis of RLS aims to: 1) distinguish RLS from other disorders with RLS-like symptoms and 2) identify secondary forms, with investigation of underlying diseases. The treatment of RLS demands a clinical evaluation to rule out and cure causes of secondary RLS, including iron supplementation when deficient, and to eliminate the triggering factors. The presence of neuropathy should be especially investigated in nonhereditary, late-onset RLS, in view of a possible treatment of the underlying disease. The first line treatment for idiopathic RLS is represented by dopamine agonists, in particular nonergot-derived ropinirole and pramipexole, whereas ergot dopamine agonists (cabergoline and pergolide) are no longer in first-line use given the risks of cardiac valvulopathy. Although no comparative trials have been published, a meta-analysis of pramipexole versus ropinirole suggests differences in efficacy and tolerability favoring pramipexole.

Restless legs syndrome in diabetic neuropathy: a frequent manifestation of small fiber neuropathy

As the occurrence of restless legs syndrome (RLS) in diabetes is controversial, the aim of this study was to assess the prevalence of RLS in a cohort of patients with diabetic neuropathy and to analyze the features of the associated neuropathy. We investigated the occurrence of RLS diagnosed in accordance with the criteria of the International Restless Legs Syndrome Study Group in a cohort of patients with polyneuropathy and mononeuropathy multiplex associated with diabetes mellitus (DM), or impaired glucose tolerance (IGT), or impaired fasting glucose (IFG) in a retrospective study. RLS was present in 33/99 patients with neuropathy associated with DM/IGT/IFG (84 with distal polyneuropathy and 15 with multiple mononeuropathy). Comparing patients with or without RLS, small fiber sensory neuropathy was more common in the RLS patients (15/33 vs. 15/66), as were symptoms of burning feet (10/33 vs. 6/66). In several patients, RLS was responsive to neuropathic pain medications. The frequent occurrence of RLS in association with thermal dysesthesias may reflect the involvement of small sensory fibers in the form of hyperexcitable C fibers or A-delta fiber deafferentation. We suggest that RLS may be triggered by abnormal sensory inputs from small fibers, especially involved in neuropathy associated with DM/IGT/IFG. Our data show that RLS is a relevant feature of diabetic neuropathy, as a frequent and potentially treatable manifestation of small fiber involvement in the course of DM and IGT/IFG.

Restless legs syndrome and polyneuropathy

Restless legs syndrome (RLS), diagnosed according to the International RLS Study Group criteria, was investigated in 97 consecutive patients with polyneuropathy and found in 29 patients. RLS patients were more often women (22 of 29 vs. 33 of 68; P = 0.015), mainly with sensory neuropathy of small fiber type (15 of 29 vs. 16 of 68; P = 0.009). Changes of sensory action potentials were significantly less severe in RLS patients. In the RLS group, acquired neuropathies, and in particular dysimmune neuropathies, were significantly more frequent (27/29 vs. 46/68; P = 0.009). Thus, RLS is frequent in acquired polyneuropathy of sensory type and mild entity, mainly in women.

[Primary bone leiomyosarcoma. Anatomo-clinical case with immunohistochemistry study and review of the literature]

We describe a primary leiomyosarcoma arising in the proximal part of the right tibia of a 38-year-old man. The diagnosis was confirmed by immunohistochemistry (positivity of tumor cells for alpha smooth muscle actin, HHF 35, desmin and vimentin). To the best of our knowledge, this is the 49th documented case of primary leiomyosarcoma of bone outside the facial skeleton. This exceptional tumor arises more commonly in adults (mean age: 53 years) and in the long bones of lower limbs, near the knee. The most frequent symptom is pain with or without swelling or fracture. Radiological findings invariably consist of a non specific osteolytic lesion. Although their histological appearance does not differ from that of extraosseous leiomyosarcomas, their diagnosis is difficult and often requires immunohistochemical and/or ultrastructural study. From a practical point of view, the diagnosis of primary leiomyosarcoma of bone also requires an intensive review of the case history and of previous pathology. This is necessary in order to eliminate an extraosseous primary site (mainly in uterus, gastrointestinal tract and soft tissues). As well as clinicopathological features, modes of treatment and results are also reviewed.