Persistence of Treponema pallidum IgM antibodies in serum: What is their meaning?

We studied the detection of Treponema pallidum (TP)-IgM antibodies in the serum of 69 patients treated for syphilis. The persistence of TP-IgM antibodies in serum for more than 3 years was the only clue to suspect an active infection and, therefore, to investigate a central nervous system involvement.

CD19+ B cell values predict the increase of anti-SARS CoV2 antibodies in fingolimod-treated and COVID-19-vaccinated patients with multiple sclerosis.

BACKGROUND: Treatment with fingolimod for multiple sclerosis (MS) reduces the efficacy of COVID-19 vaccination. The aim of this exploratory study was to evaluate whether main lymphocyte subsets and demographic features correlated to the subsequent increase in anti-SARS-CoV2 antibodies following the third dose of COVID-19 vaccination in fingolimod-treated MS patients. METHODS: This was a prospective single-center observational exploratory study including a subgroup of adult patients with MS (pwMS) in treatment with fingolimod who underwent COVID-19 vaccination. The association of anti-SARS-CoV2 antibody levels (reported as the Log10 of the difference between the post and pre third dose levels) with the total number and percentage of CD3+ T and CD19+ B was assessed by a linear regression model adjusted for age and sex. RESULTS: We found that peripheral blood CD19+ B lymphocytes before the third dose of vaccination in pwMS treated with fingolimod predict the subsequent increase of anti-SARS-CoV2 antibodies. CONCLUSION: This work suggests that evaluating the percentage of CD19+ B cells may be important to identify patients at risk of not producing SARS-CoV-2 antibodies, with possible reduced protection from COVID-19.

An eleven-year history of Vanishing White Matter Disease in an adult patient with no cognitive decline and EIF2B5 mutations. A case report.

Vanishing White Matter Disease (VWMD) is a rare autosomal recessive leukoencephalopathy . The classical presentation is characterized by a severe cerebellar ataxia, spasticity, neurological deterioration with a chronic progressive course and episodes of acute neurological deterioration after stress conditions.We report a 52-year-old man with VWMD and atypical features who manifested two major events of transient aphasia eleven years apart with complete recovery in 48 hours. No cognitive decline was present. Brain MRI revealed typical aspects of VWMD including diffuse leukoencephalopathy with relative sparing of U-fibers. We identified the presence of c.592G>A (p.Glu198Lys) and c.1360 C>T (p.Pro454Ser) mutations in EIF2B5.

Predictors of Ocrelizumab Effectiveness in Patients with Multiple Sclerosis.

Data regarding effectiveness and safety of ocrelizumab in the post-marking setting are lacking. The aim of our study was to provide effectiveness and safety data of ocrelizumab treatment in patients with relapsing-remitting (RR-) and progressive multiple sclerosis (PMS) and to evaluate clinical and immunological predictors of early treatment response. In this single-center prospective observational study, we investigated effectiveness outcomes (time-to-confirmed disability worsening, time-to-first relapse, time-to-first evidence of MRI activity and time-to-first evidence of disease activity), clinical and immunological predictors of early treatment response, and incidence of adverse events (AEs). One hundred and fifty-three subjects were included (93 RRMS; 84 females). Median follow-up was 1.9 (1.3-2.7). At 2-year follow-up (FU), disability worsening-free survival were 90.5%, 64.7%, and 68.8% for RRMS, primary-progressive MS (PPMS), and secondary-progressive MS (SPMS) patients, respectively. At 2-year FU, 67.1%, 72.7%, and 81.3% of patients with RRMS, PPMS, and SPMS were free of MRI activity, with NEDA-3 percentages of 62.1%, 54.6%, and 55.1%, respectively. Lower baseline EDSS was independently associated with a reduced risk of disability worsening (HR(95%CI) = 1.45(1.05-2.00), p = 0.024) and previous treatment exposure was independently associated with increased probability of radiological activity (HR = 2.53(1.05-6.10), p = 0.039). At 6-month FU, CD8 + cell decrease was less pronounced in patients with inflammatory activity (p = 0.022). Six patients (3.9%) discontinued ocrelizumab due to severe AEs. Our findings suggest that ocrelizumab is an effective treatment in real-world patients with RRMS and PMS, with a manageable safety profile. Better outcomes were observed in treatment-naïve patients and in patients with a low baseline disability level. Depletion of CD8 + cells could underlie early therapeutic effects of ocrelizumab.

Spasticity, spastic dystonia, and static stretch reflex in hypertonic muscles of patients with multiple sclerosis.

OBJECTIVE: To investigate prevalence of EMG patterns underlying hypertonia in multiple sclerosis (MS) and whether these patterns indicate different levels of spinal excitability. METHODS: We investigated the EMG activity recorded from 108 hypertonic muscles of 59 consecutive MS patients. To investigate spastic dystonia (SD), we looked for the presence of EMG activity in muscles in a resting position. To investigate dynamic stretch reflex (DSR) and static stretch reflex (SSR), we looked for the presence of EMG activity in response to a manually performed passive stretch of the muscle. RESULTS: DSR was evoked in 104 muscles. In 51 muscles, DSR was the sole EMG activity. This pattern corresponds to the classical notion of spasticity, and was predominant in extensors. In contrast, SSR was detected in 48 muscles - predominantly in flexors. SD was observed in 28 muscles, showing even distribution in flexor and extensor muscles. Only in the flexors, SSR was associated with a larger DSR compared to spasticity. CONCLUSIONS: These findings likely depend on the central effects of both flexor and extensor spindle afferents on the homonymous spinal motor neurons. SIGNIFICANCE: Improving our capacity to assess spinal excitability in MS patients.

Autologous hematopoietic stem cell transplantation following alemtuzumab therapy in aggressive multiple sclerosis: A report of three cases.

The management of multiple sclerosis patients with persistent disease activity under alemtuzumab treatment is not established yet. Concerns have been raised on the safety of autologous haematopoietic stem cell transplantation (aHSCT) after alemtuzumab treatment because of the risk of serious infectious adverse events. We report short-term safety and efficacy data from three patients treated with aHSCT following alemtuzumab treatment. Early adverse events were consistent with expected transplant toxicities. All patients were free of disease activity at the last follow-up. Our data suggest that aHSCT can be considered as a rescue treatment strategy for MS patients with persistent disease activity during alemtuzumab treatment.

CSF sphingomyelin: a new biomarker of demyelination in the diagnosis and management of CIDP and GBS.

OBJECTIVE: To validate sphingomyelin (SM) dosage in the cerebrospinal fluid (CSF) of patients affected by chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and Guillain-Barré syndrome (GBS) as a reliably assessable biomarker. METHODS: We prospectively enrolled 184 patients from six Italian referral centres, in whom CSF SM levels were quantified by a fluorescence-based assay optimised and patented in our laboratory. RESULTS: We confirmed increased levels of SM in the CSF of patients affected by typical CIDP (n=35), atypical CIDP (n=18) and acute inflammatory demyelinating polyradiculoneuropathy, AIDP (n=12) compared with patients affected by non-demyelinating neurological diseases, used as controls (n=85) (p<0.0001, p=0.0065 and p<0.0001, respectively). In patients with CIDP classified for disease stage, SM was higher in active CIDP compared with both controls and stable CIDP (p<0.0001), applying for a selective tool to treatment tailoring or withdrawal. SM was also increased in AIDP compared with axonal GBS, discerning the demyelinating from axonal variant of the disease. SM did not correlate with CSF protein levels, stratifying patients independently from commonly used CSF indexes, and displaying high specificity to avoid potential misdiagnosis. Finally, SM correlated with the main clinical scores and some neurophysiological parameters in patients with CIDP and AIDP. CONCLUSIONS: CSF SM is a diagnostic and staging wet biomarker for acquired demyelinating neuropathies and may effectively improve the management of patients affected by GBS and CIDP.

COVID-19-related and not related Guillain-Barré syndromes share the same management pitfalls during lock down: The experience of Liguria region in Italy.

Recently, during the pandemic infection of the novel SARS-CoV-2, some cases of Guillan-Barré Syndrome (GBS) have been reported. The aim of this work is to report the natural history of patients with GBS, both COVID and not-COVID related, hospitalized in Liguria region, during lock down period, in order to assess clinical features of both groups and possible managements pitfalls due to pandemic emergency. Fifteen GBS patients were admitted to the Hospitals of Liguria, from February 15th to May 3rd 2020, six with SARS-CoV-2 infection and nine without infection. In COVID-19 related GBS five patients presented with classical GBS and one with variant. Two patients presented neurologic symptoms during or shortly after the viral syndrome, suggesting the pattern of a para-infectious profile. Multi-organ involvement, delay in the diagnosis, incomplete work up and start of therapy, were registered in 50% of cases with a GBS-Disability scale ≥4 at follow-up evaluation. In not-COVID-19 related GBS, main problem was diagnostic delay. In three patients the first neurological observation took place after a mean of 33,6 days. Moreover, five patients went to emergency room after an average of 30 days since the onset of neurological symptoms because of fear of contagion. In conclusion, not only SARS-CoV-2 infection can cause GBS, but it can also, due to effects of pandemic on the health organization, affect the outcome of patients with not COVID-19 related GBS.

Tailoring B cell depletion therapy in MS according to memory B cell monitoring.

OBJECTIVE: We wanted to evaluate efficacy on inflammatory parameters of rituximab (RTX)-personalized reinfusion scheme using a memory B cell-based treatment regimen. METHODS: This is a prospective, uncontrolled, open-label study including patients with MS treated with RTX in 2 Italian MS units. All patients were treated with RTX induction, followed by maintenance infusion at the dosage of 375 mg/m2, according to memory B cell repopulation (0.05% of peripheral-blood mononuclear cells [PBMCs] for the first 2 years, 0.1% of PBMC for the third year). MS activity was assessed as clinical or MRI activity. RESULTS: One hundred two patients were included in the analysis. Mean follow-up was 2.40 years (range 0.57-7.15 years). The annualized relapse rate (ARR) was 0.67 in the year before RTX start and decreased to 0.01 in the 3 years after RTX initiation (global ARR). The proportion of patient with MS activity (i.e., relapse or MRI activity) was 63.16% in the year before RTX start and decreased to 8.7% (0-6 months), 1.3% (6-12 months), 0% (12-24 months), and 0% (24-36 months). Annualized RTX infusion rates were 1.67 (95% confidence interval [CI]: 1.43-1.94), 0.76 (95% CI: 0.58-0.98), and 0.78 (95% CI: 0.52-1.12) for the first 3 years after RTX initiation, respectively. Patients were reinfused with a mean infusion interval of 367 days (range 181-839 days). CONCLUSION: The results of this study show that the memory B cell-based RTX reinfusion protocol is able to reduce the mean number of RTX reinfusions with persistent reduction of disease activity. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that for patients with MS, a memory B cell-based RTX reinfusion protocol can reduce the mean number of RTX reinfusions with persistent reduction of disease activity.

Nabiximols discontinuation rate in a large population of patients with multiple sclerosis: a 18-month multicentre study.

INTRODUCTION: Delta-δ-tetrahydrocannabinol and cannabidiol (THC:CBD) oromucosal spray is used as an add-on therapy option for moderate to severe multiple sclerosis (MS) spasticity resistant to other medications. Aims of this study were to provide real-life data on long-term clinical outcomes in a large population of Italian patients treated with THC:CBD and to evaluate predictors of THC:CBD therapy continuation. MATERIALS AND METHODS: This prospective observational multicentre Italian study screened all patients with MS consecutively included in the Agenzia Italiana del Farmaco e-registry at the start of THC:CBD treatment (baseline), after 4 weeks (T1), 12±3 weeks (T2), 24±3 weeks (T3), 48±3 weeks (T4) and 72±3 weeks (T5) from baseline. RESULTS: A total of 1845 patients were recruited from 32 MS Italian centres. At T1, 1502 (81.4%) of patients reached a Numerical Rating Scale (NRS) improvement of ≥20%, with an NRS reduction of 26.9% at T1 and of 34.4% at T5. At T5, 725 patients (48.3% of 1502) discontinued treatment with highest discontinuation rate at T2 and T3. Daily number of puffs was generally stable through the observation period. The multivariate analysis showed that higher NRS scores at baseline (OR 2.28, 95% CI 1.15 to 6.36, p<0.01) and higher differences of NRS between T0 and T1 (OR 2.11, 95% CI 1.08 to 8.26, p<0.05) were associated with an increased probability to continue therapy after 18 months. DISCUSSION: THC:CBD effects were sustained for 18 months with a relatively stable number of puffs per day. About 50% of patients abandoned THC:CBD therapy for loss of efficacy or adverse events.

Long-term assessment of the cognitive effects of nabiximols in patients with multiple sclerosis: A pilot study.

OBJECTIVE: Moderate to severe spasticity is commonly reported in Multiple Sclerosis (MS) and its management is still a challenge. Cannabinoids were recently suggested as add-on therapy for the treatment of spasticity and chronic pain in MS but there is no conclusive scientific evidence on their safety, especially on cognition and over long periods. The aim of this prospective pilot study was to assess the long-term effects of a tetrahydrocannabinol-cannabidiol (THC/CBD) oromucosal spray (Sativex®) on cognition, mood and anxiety. PATIENTS AND METHODS: An extensive and specific battery of neuropsychological tests (Symbol Digit Modalities Test-SDMT, California Verbal Learning Test-CVLT, Brief Visuospatial Memory Test-BVMT; PASAT-3 and 2; Free and Cued Selective Remind Test-FCSRT, Index of Sensitivity of Cueing-ISC) was applied to longitudinally investigate different domains of cognition in 20 consecutive MS patients receiving Sativex for spasticity. The primary endpoint was to assess any variation in cognitive performance. Secondary outcomes regarding mood and anxiety were investigated by means of Beck Depression Inventory (BDI) and Hamilton Anxiety Rating Scale (HAM-A). Any change in patients' spasticity was evaluated using the 0-10 Numerical Rating Scale (NRS). RESULTS: Twenty per protocol patients were followed up and evaluated at baseline, 6 and 12 months. Domains involving processing speed and auditory verbal memory significantly improved within the first 6 months of therapy (SDMT: p < 0.001; CVLT: p = 0.0001). Mood and anxiety did not show any significant variation. Additionally, the NRS score significantly improved since the beginning (p < 0.0001). CONCLUSIONS: These results are encouraging in supporting possible long-term benefits of Sativex on cognition and a wider role than symptom alleviator. Further studies on larger groups of patients would be necessary in order to test this intriguing possibility.

Fingolimod and Dimethyl-Fumarate-Derived Lymphopenia is not Associated with Short-Term Treatment Response and Risk of Infections in a Real-Life MS Population.

BACKGROUND: The association between treatment-related lymphopenia in multiple sclerosis, drug efficacy and the risk of infections is not yet fully understood. OBJECTIVE: The objective of this study was to assess whether lymphopenia is associated with short-term treatment response and infection rate in a real-life multiple sclerosis population treated with fingolimod and dimethyl-fumarate. We assessed the associations between baseline absolute lymphocyte count and the lymphocyte mean percentage decrease at 6 and 12 months with treatment response and the occurrence of adverse events over 12 months in the entire cohort of patients and in the two treatment groups separately. METHODS: This is a retrospective observational real-world study of patients with multiple sclerosis treated with fingolimod and dimethyl-fumarate at the MS Center of the University of Genoa between 2011 and 2018. Patients with at least 12 months of follow-up were eligible if [1] they had an Expanded Disability Status Scale assessment at baseline and 12 months after treatment onset, [2] they had undergone brain magnetic resonance imaging at baseline and after 12 months, and [3] absolute lymphocyte counts were available at baseline, 6 and 12 months. Patients shifting from dimethyl-fumarate to fingolimod or vice versa were excluded from the analysis. RESULTS: In total, 137 and 75 patients treated with fingolimod and dimethyl-fumarate, respectively, were included in the analysis. At 12 months, fingolimod-treated patients were more likely to experience grade II and grade III lymphopenia compared with dimethyl-fumarate patients (p < 0.001, χ2 = 94) and had a higher lymphocyte mean percentage decrease (p < 0.001, U = 540). A higher number of previous therapies and a lower baseline absolute lymphocyte count were predictors of lymphopenia at 6 months (p = 0.047, odds ratio = 1.60 and p = 0.014, odds ratio = 1.1) and 12 months (p = 0.003, odds ratio = 1.97 and p = 0.023, odds ratio = 1.1). In fingolimod-treated patients only, female sex and a higher Expanded Disability Status Scale score were predictors of lymphopenia at 12 months (p = 0.006, odds ratio = 7.58 and p = 0.03, odds ratio = 1.56). Neither absolute lymphocyte count at 6 and 12 months nor the mean percentage decrease at 6 and 12 months predicted No Evidence of Disease Activity (NEDA-3) status at 1 year, the occurrence of relapses, disease activity on MRI or disability progression. CONCLUSIONS: Our findings suggest that peripheral blood lymphocyte changes are not associated with short-term treatment response and with the rate of infections during fingolimod and dimethyl-fumarate treatment in real-world patients. Higher treatment exposure and a lower baseline absolute lymphocyte count are risk factors for lymphopenia development during fingolimod and dimethyl-fumarate therapy.

Ecological impact of isolated cognitive relapses in MS.

Isolated cognitive relapses (ICRs) are transient deficits in cognitive performance that are the only presentation of a multiple sclerosis (MS) relapse. Here, we evaluated the impact of ICRs on cognitive difficulties in daily activities (assessed with the Multiple Sclerosis Neuropsychological Screening Questionnaire, Informant Version (MSNQ-I)) to characterize ICRs' clinical relevance. We used 2-year-long retrospective data to compare 15 relapsing-remitting MS (RRMS) patients with ICRs with 57 RRMS patients presenting an asymptomatic gadolinium enhancing lesion (and no-ICRs). ICRs were associated not only with neuropsychological performance decline but also with an increase in the daily cognitive difficulties. These findings support the ecological relevance of ICRs.

Reciprocal Incremental Value of 18F-FDG-PET and Cerebrospinal Fluid Biomarkers in Mild Cognitive Impairment Patients Suspected for Alzheimer's Disease and Inconclusive First Biomarker.

BACKGROUND: In Alzheimer's disease (AD) diagnosis, both cerebrospinal fluid (CSF) biomarkers and FDG-PET sometimes give inconclusive results. OBJECTIVE: To evaluate the incremental diagnostic value of FDG-PET over CSF biomarkers, and vice versa, in patients with mild cognitive impairment (MCI) and suspected AD, in which the first biomarker resulted inconclusive. METHODS: A consecutive series of MCI patients was retrospectively selected from two Memory Clinics where, as per clinical routine, either the first biomarker choice is FDG-PET and CSF biomarkers are only used in patients with uninformative FDG-PET, or vice versa. We defined criteria of uncertainty in interpretation of FDG-PET and CSF biomarkers, according to current evidence. The final diagnosis was established according to clinical-neuropsychological follow-up of at least one year (mean 4.4±2.2). RESULTS: When CSF was used as second biomarker after FDG-PET, 14 out of 36 (39%) received informative results. Among these 14 patients, 11 (79%) were correctly classified with respect to final diagnosis, thus with a relative incremental value of CSF over FDG-PET of 30.6%. When FDG-PET was used as second biomarker, 26 out of 39 (67%) received informative results. Among these 26 patients, 15 (58%) were correctly classified by FDG-PET with respect to final diagnosis, thus with a relative incremental value over CSF of 38.5%. CONCLUSION: Our real-world data confirm the added values of FDG-PET (or CSF) in a diagnostic pathway where CSF (or FDG-PET) was used as first biomarkers in suspected AD. These findings should be replicated in larger studies with prospective enrolment according to a Phase III design.

Relationship between retinal inner nuclear layer, age, and disease activity in progressive MS.

OBJECTIVE: To investigate whether inner nuclear layer (INL) thickness as assessed with optical coherence tomography differs between patients with progressive MS (P-MS) according to age and disease activity. METHODS: In this retrospective longitudinal analysis, differences in terms of peripapillary retinal nerve fiber layer (pRNFL), ganglion cell layer + inner plexiform layer (GCIPL), INL and T1/T2 lesion volumes (T1LV/T2LV) were assessed between 84 patients with P-MS and 36 sex- and age-matched healthy controls (HCs) and between patients stratified according to age (cut-off: 51 years) and evidence of clinical/MRI activity in the previous 12 months RESULTS: pRNFL and GCIPL thickness were significantly lower in patients with P-MS than in HCs (p = 0.003 and p < 0.0001, respectively). INL was significantly thicker in patients aged < 51 years compared to the older ones and HCs (38.2 vs 36.5 and 36.7 µm; p = 0.038 and p = 0.04, respectively) and in those who presented MRI activity (new T2/gadolinium-enhancing lesions) in the previous 12 months compared to the ones who did not and HCs (39.5 vs 36.4 and 36.7 µm; p = 0.003 and p = 0.008, respectively). Recent MRI activity was significantly predicted by greater INL thickness (Nagelkerke R2 0.36, p = 0.001). CONCLUSIONS: INL thickness was higher in younger patients with P-MS with recent MRI activity, a criterion used in previous studies to identify a specific subset of patients with P-MS who best responded to disease-modifying treatment. If this finding is confirmed, we suggest that INL thickness might be a useful tool in stratification of patients with P-MS for current and experimental treatment choice.

CSF oligoclonal bands and normal appearing white matter periventricular damage in patients with clinically isolated syndrome suggestive of MS.

BACKGROUND: A periventricular gradient of normal appearing white matter (NAWM) damage has been described in multiple sclerosis (MS), including subjects with clinically isolated syndrome (CIS). The pathological mechanisms underlying this gradient is not currently understood. METHODS: 34 CIS subjects were enrolled and underwent cerebrospinal fluid oligo-clonal bands (CSF-OCB) evaluation. Moreover, all CIS subjects and 24 healthy controls underwent a brain MRI scan. Diffusion weighted imaging was used to compute mean diffusivity (MD) values in periventricular and deep NAWM for all groups. RESULTS: CSF-OCB were present in 24 CIS subjects (CSF-OCB+) out of 34 tested. Periventricular NAWM MD values were significantly higher in CIS subjects with than in those without CSF-OCB (0.78 ± 0.06 mm3/10-3 vs. 0.72 ± 0.06 mm3/10-3; p = 0.01), while there was no difference between groups in deep NAWM MD values. The periventricular gradient of damage, expressed in z score based on healthy controls data, was more marked in CSF-OCB+ than in CSF-OCB- (0.65 ± 0.05 vs. 0.17 ± 0.04 p < 0.001). There was no difference in periventricular lesion load between the two groups. CONCLUSIONS: In CIS, the presence of CSF-OCB is associated with the severity of periventricular NAWM damage gradient. Intrathecal inflammation could play a role in NAWM damage distribution.

Composite MRI measures and short-term disability in patients with clinically isolated syndrome suggestive of MS.

BACKGROUND: The use of composite magnetic resonance imaging (MRI) measures has been suggested to better explain disability in patients with multiple sclerosis (MS). However, little is known about the utility of composite scores at the earliest stages of the disease. OBJECTIVE: To investigate whether, in patients with clinically isolated syndrome (CIS), a composite MRI measure, rather than the single metrics, would explain conversion to MS and would better correlate with disability at baseline and at 1 year of follow-up. METHODS: Corticospinal tract (CST), corpus callosum (CC) and optic radiation (OR) volume, fractional anisotropy (FA), and mean diffusivity (MD) values were measured in 27 CIS patients and 24 healthy controls (HCs). Z-scores of FA, MD, and tract volume measures were calculated in patients, based on the corresponding measures obtained from HCs, and then combined in a composite score for each tract. Correlations between Z-scores at baseline and both the Expanded Disability Status Scale (EDSS) at baseline and at follow-up (FU-EDSS) were investigated. RESULTS: Only CST, CC, and OR composite scores as well as the CST volume were significantly associated with FU-EDSS ( p = 0.005, p = 0.007, p = 0.020, and p = 0.010, respectively). CONCLUSION: The combination of MRI measures rather than the individual metrics better captured the association between tissue damage in both the CC, OR and CST and short-term follow-up disability.

Cerebrospinal fluid analysis and the determination of oligoclonal bands.

This document presents the guidelines for the cerebrospinal fluid (CSF) analysis and the determination of oligoclonal bands (OCBs) as pivotal tests in neuroinflammatory pathologies of the central nervous system. The guidelines have been developed following a consensus process built on questionnaire-based surveys, internet contacts, and discussions at workshops of the sponsoring Italian Association of Neuroimmunology (AINI) congresses. Essential clinical information on the pathologies in which the CSF analysis is indicated, and, particularly, on those characterized by the presence of OCBs in the intrathecal compartment, indications and limits of CSF analysis and OCB determination, instructions for result interpretation, and agreed laboratory protocols (Appendix) are reported for the communicative community of neurologists and clinical pathologists.

Spasticity and spastic dystonia: the two faces of velocity-dependent hypertonia.

BACKGROUND: Spasticity and spastic dystonia are two separate phenomena of the upper motor neuron syndrome. Spasticity is clinically defined by velocity-dependent hypertonia and tendon jerk hyperreflexia due to the hyper-excitability of the stretch reflex. Spastic dystonia is the inability to relax a muscle leading to a spontaneous tonic contraction. Both spasticity and spastic dystonia are present in patients who are at rest; however, only patients with spasticity are actually able to kept their muscles relaxed prior to muscle stretch. The idea that has inspired the present work is that also in patients with spastic dystonia the stretch reflex is likely to be hyper-excitable. Therefore, velocity-dependent hypertonia could be mediated not only by spasticity, but also by spastic dystonia. METHODS: Tonic stretch reflexes in the rectus femoris muscle were evoked in 30 patients with multiple sclerosis showing velocity-dependent hypertonia of leg extensors and the habituation of the reflex was studied. Moreover, the capability of relax the muscle prior to muscle stretch (spastic dystonia) was also investigated. RESULTS: A tonic stretch reflex was evoked in all the enrolled patients. 73% of the patients were able to relax their rectus femoris muscle prior to stretch (spasticity). In the overwhelming majority of these patients, the tonic stretch reflex decreased during repeated stretches. In the remaining 27% of the subjects, the muscle was tonically activated prior to muscle stretch (spastic dystonia). In the patients in whom spastic dystonia progressively increased over the subsequent stretches (50% of the subjects with spastic dystonia), the habituation of the reflex was replaced by a progressive reflex facilitation. DISCUSSION: This study shows for the first time that velocity-dependent hypertonia can be caused by two distinct phenomena: spasticity and spastic dystonia. The habituation of the tonic stretch reflex, which is a typical feature of spasticity, is replaced by a reflex facilitation in the half of the subject with spastic dystonia. These preliminary findings suggest that differentiating the two types of velocity-dependent muscle hypertonia (spasticity and spastic dystonia) could be clinically relevant.

Sphingomyelin as a myelin biomarker in CSF of acquired demyelinating neuropathies.

Fast, accurate and reliable methods to quantify the amount of myelin still lack, both in humans and experimental models. The overall objective of the present study was to demonstrate that sphingomyelin (SM) in the cerebrospinal fluid (CSF) of patients affected by demyelinating neuropathies is a myelin biomarker. We found that SM levels mirror both peripheral myelination during development and small myelin rearrangements in experimental models. As in acquired demyelinating peripheral neuropathies myelin breakdown occurs, SM amount in the CSF of these patients might detect the myelin loss. Indeed, quantification of SM in 262 neurological patients showed a significant increase in patients with peripheral demyelination (p = 3.81 * 10 - 8) compared to subjects affected by non-demyelinating disorders. Interestingly, SM alone was able to distinguish demyelinating from axonal neuropathies and differs from the principal CSF indexes, confirming the novelty of this potential CSF index. In conclusion, SM is a specific and sensitive biomarker to monitor myelin pathology in the CSF of peripheral neuropathies. Most importantly, SM assay is simple, fast, inexpensive, and promising to be used in clinical practice and drug development.