Serum and cerebrospinal fluid neurofilament light chains measured by SIMOA™, Ella™, and Lumipulse™ in multiple sclerosis naïve patients.

BACKGROUND: Neurofilament light chains (NfL) are cytoskeletal biomarkers of axonal damage, about 40-fold higher in cerebrospinal fluid (CSF) compared to serum, and requiring ultrasensitive techniques to be measured in this latter fluid. OBJECTIVES: To compare CSF and serum NfL levels in multiple sclerosis (MS) patients using different platforms. METHODS: 60 newly diagnosed relapsing-remitting MS patients (38 females; median age: 36.5 years, range: 15-60) were enrolled before steroid or disease-modifying treatments. CSF and serum NfL were measured with: the commercial Ella™ microfluidic platform (Bio-Techne), the Lumipulse™ Chemiluminescent Enzyme ImmunoAssay (Fujirebio), and the SIMOA™ on the SR-X instrument using NF-light assays (Quanterix). RESULTS: CSF and serum NfL absolute levels strongly correlated between assays, although being more elevated with Ella™. Passing-Bablok regression showed high agreement in measuring CSF NfL between assays (with greater proportional difference using Ella™), and very high agreement for serum comparing SIMOA™ and Lumipulse™. Similarly, the Bland-Altman comparison evidenced lower biases for Lumipulse™ for both fluids. CONCLUSIONS: CSF and serum NfL in naïve MS patients are reliably measured with all assays. Although not interchangeable, SIMOA™ and Lumipulse™ showed high agreement for serum and CSF values.

Do patients' and referral centers' characteristics influence multiple sclerosis phenotypes? Results from the Italian multiple sclerosis and related disorders register.

BACKGROUND: Multiple sclerosis (MS) is characterized by phenotypical heterogeneity, partly resulting from demographic and environmental risk factors. Socio-economic factors and the characteristics of local MS facilities might also play a part. METHODS: This study included patients with a confirmed MS diagnosis enrolled in the Italian MS and Related Disorders Register in 2000-2021. Patients at first visit were classified as having a clinically isolated syndrome (CIS), relapsing-remitting (RR), primary progressive (PP), progressive-relapsing (PR), or secondary progressive MS (SP). Demographic and clinical characteristics were analyzed, with centers' characteristics, geographic macro-areas, and Deprivation Index. We computed the odds ratios (OR) for CIS, PP/PR, and SP phenotypes, compared to the RR, using multivariate, multinomial, mixed effects logistic regression models. RESULTS: In all 35,243 patients from 106 centers were included. The OR of presenting more advanced MS phenotypes than the RR phenotype at first visit significantly diminished in relation to calendar period. Females were at a significantly lower risk of a PP/PR or SP phenotype. Older age was associated with CIS, PP/PR, and SP. The risk of a longer interval between disease onset and first visit was lower for the CIS phenotype, but higher for PP/PR and SP. The probability of SP at first visit was greater in the South of Italy. DISCUSSION: Differences in the phenotype of MS patients first seen in Italian centers can be only partly explained by differences in the centers' characteristics. The demographic and socio-economic characteristics of MS patients seem to be the main determinants of the phenotypes at first referral.

Intrathecal kappa free light chains as markers for multiple sclerosis.

Cerebrospinal fluid (CSF) kappa free light chain (KFLC) index has been described as a reliable marker of intrathecal IgG synthesis to diagnose multiple sclerosis (MS). Our aims were: (1) to compare the efficiency of KFLC through different interpretation approaches in diagnosing MS. (2) to evaluate the prognostic value of KFLC in radiologically and clinically isolated syndromes (RIS-CIS). We enrolled 133 MS patients and 240 with other neurological diseases (93 inflammatory including 18 RIS-CIS, 147 non-inflammatory). Albumin, lambda free light chain (LFLC) and KFLC were measured in the CSF and serum by nephelometry. We included two groups of markers: (a) corrected for blood-CSF barrier permeability: immunoglobulin G (IgG), KFLC and LFLC indexes. (b) CSF ratios (not including albumin and serum-correction): CSF KFLC/LFLC, CSF KFLC/IgG, CSF LFLC/IgG. KFLC were significantly higher in MS patients compared to those with other diseases (both inflammatory or not). KFLC index and CSF KFLC/IgG ratio showed high sensitivity (93% and 86.5%) and moderate specificity (85% and 88%) in diagnosing MS. RIS-CIS patients who converted to MS showed greater KFLC index and CSF KFLC/IgG. Despite OB are confirmed to be the gold-standard to detect intrathecal IgG synthesis, the KFLC confirmed their accuracy in MS diagnosis. A "kappa-oriented" response characterizes MS and has a prognostic impact in the RIS-CIS population.

Kappa free light chains could predict early disease course in multiple sclerosis.

BACKGROUND: Cerebrospinal fluid (CSF) kappa free light chains (KFLC) have been suggested as quantitative alternative to oligoclonal bands (OB) in multiple sclerosis (MS) diagnosis. Despite OB have been associated to poor disease prognosis, little is known on KFLC in predicting MS early progression. Our aim is to evaluate the prognostic value of KFLC in a cohort of Italian MS patients. METHODS: 100 patients (64 females) underwent CSF analysis during their diagnostic MS work-up. We collected clinical/paraclinical features (gender, age at onset, clinical course, early MS treatments (within 1 year), gadolinium-enhancing (Gd+) lesions), calculated K index (ratio CSF-serum KFLC and albumin), and MS severity score (MSSS) at last follow up (minimum 1 year). Statistical analysis included Mann-Whitney descriptive analysis, Spearman correlation for independent samples, and linear regression for significant predictors. RESULTS: K index resulted a significant predictor for disability over time being higher in patients who developed greater MSSS. Accordingly, K index was also significantly increased in patients undergoing early versus delayed treatment (N = 50/100, p = 0.046). A similar role in predicting MS disability was confirmed for age at onset. No other factors were retained in our regression model. Of note, K index was not associated to known MS prognostic markers such as gender, age at onset, and Gd+ lesions (N = 31/96). CONCLUSION: Our study suggests KFLC as a CSF quantitative marker to predict early disability in MS (despite not being a substitute for OB).

A case of progressive non-fluent aphasia as onset of amyotrophic lateral sclerosis with frontotemporal dementia.

The association between Amyotrophic Lateral Sclerosis (ASL) and FrontoTemporal Dementia (FTD) is well known. Most of reports describing ASL-FTD cases show a strong association between ALS and the behavioural form of FTD. Conversely, the association between ALS and pure Semantic Dementia or Progressive Non-Fluent Aphasia (PNFA) is extremely rare, ranging from 1 to 3%. A clinical phenotype characterized by a rapidly progressive aphasic dementia and motoneuron disease (MND) has been described in few case reports; since the updating of PNFA diagnostic criteria in 2011, no clinical report has been related. We want to describe a case of patient presented, at the onset, as PNFA who developed, one year later, ALS with bulbar onset. The patient was screened for the main genes causing or associated with MND and/or dementia but no variants with a pathogenetic effect were observed.

MOG-antibody demyelinating diseases: a case of post-partum severe rhombencephalitis and transverse myelitis.

INTRODUCTION: Myelin oligodendrocyte glycoprotein antibodies (MOG-IgG) associated disorders present with a spectrum of clinical pictures including brainstem involvement. CASE REPORT: A patient with the sudden onset of a post-partum severe rhombencephalitis causing respiratory failure (12 years after a mild transverse myelitis). Despite the aggressive clinical course, she had an impressive recovery after plasmapheresis, and no further relapses on immunosuppression. CONCLUSION: MOG-IgG disorders could relapse several years after onset and involve brainstem. Good prognosis is possible after treatment.

Headache in immigrant patients: similarities and differences with Italian population.

Headache is one of the most common neurological diseases. It is well known that there are differences in the perception and in the management of pain in various populations. Immigrants represent a growing portion between neurology outpatients. We analyzed the epidemiological characteristic of headache in immigrants come to our attention, in comparison with Italians. Data collected included age at immigration, age of onset of headache, headache's type (HIS criteria), and psychiatric comorbidities. There were not substantial differences in the incidence of headache subtypes: migraine was the most frequent diagnosis in both groups, followed by tension-type headache. The incidence of depression was similar, while anxiety was significantly less frequent in immigrants. Studies on neurological diseases in immigrants are few. The data available seem to show no differences in the incidence, but rather in treatment. Our study confirms the evenness of two populations, local and foreign, afferent in a Headache Unit, according to the single similar study, except for anxiety, maybe related to language difficulties or cultural background.

Ptosis and bulbar onset: an unusual phenotype of familial ALS?

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder of upper and lower motor neurons that usually spare the oculomotor nerves. Here, we describe a case of two siblings with a familial bulbar-onset ALS both with ptosis manifested at the onset of the disease.

The measuring of substantia nigra hyperechogenicity in an Italian cohort of Parkinson disease patients: a case/control study (NOBIS Study).

Transcranial sonography (TCS) shows an increased echogenic area of the substantia nigra (SN) in patients with Parkinson disease (PD). It has been increasingly used in the diagnosis of PD and its differentiation from atypical parkinsonian syndromes. Here, we studied the diagnostic accuracy of SN TCS in Italian patients. In this blinded cross-sectional study (NOBIS study), two expert neuro-sonologists performed TCS in 25 PD patients and 29 age- and sex-matched controls. The study participants were completely hidden to the TCS investigators using large drapery. One month later, the SN TCS recordings were re-read by the initial investigator, and cross-read by the second reader. Diagnostic accuracy was estimated on the first reading, intra-reader reliability on re-reading, and inter-reader reliability on cross-readings. The mean SN echogenic area was larger in the patients (0.24 cm2) than in the controls (0.15 cm2; Mann-Whitney test, p < 0.001). SN measures did not differ between right and left, or between ipsilateral and contralateral to the clinically more affected side. There was no correlation between SN echogenicity and PD severity or duration. High intra-reader (concordance correlation coefficient 0.93) and inter-reader (0.98) agreement of SN measurements was found. The diagnostic accuracy for the detection of PD was high (area under receiver-operating characteristic curve 0.91; 95% CI 0.83-1.00) with an optimum cut-off value for SN echogenic area of 0.18 cm2 with the device used here (specificity 0.83-0.90; sensitivity 0.72-0.92). This study supports the use of SN TCS in the diagnostic workup of PD if performed by trained readers.

Polymorphisms of dopamine receptor genes and risk of visual hallucinations in Parkinson's patients.

BACKGROUND: Visual hallucinations (VHs) are frequent non-motor complication of Parkinson's disease (PD), associated to a negative prognosis. Previous studies showed an association between dopamine receptor (DR) gene (DR) variants and psychosis in Alzheimer's disease, addictions, schizophrenia, and bipolar disorder. However, there are only a few studies on DR variants and VHs in PD, which did not provide conclusive results. OBJECTIVES: The present study aimed to determine whether genetic differences of DR are associated with visual hallucinations (VHs) in a cohort of Parkinson's disease (PD) patients. METHODS: A case-control study of 84 PD subjects, 42 with and 42 without VHs,that were matched for age, gender, disease duration, and dopaminergic medication was conducted. Polymerase chain reaction for SNPs in both D1-like (DRD1A-48G [rs4532] and C62T [rs686], DRD5T798C [rs6283]) and D2-like DR (DRD2G2137A [rs1800497] and C957T [rs6277], DRD3G25A [rs6280] and G712C [rs1800828], DRD4C616G [rs747302] and nR VNTR 48bp) analyzed genomic DNA. RESULTS: Patients carrying allele T at DRD1C62T had an increased risk of VHs, expressed as OR (95 % CI, p value), of 10.7 (2.9-40, p = 0.0001). Moreover, patients with DRD1-48 GG and 62TT genotype displayed shorter time to VHs, whereas a longer time to VHs was found in subjects carrying the DRD4 CG alleles. CONCLUSIONS: PD patients with VHs display higher frequency of DR SNPs associated with increased D1-like activity and decreased D2-like activity. Our data are in line with associations reported in other neurodegenerative and psychiatric conditions. Results likely provide valuable information for personalizing pharmacological therapy in PD patients.

A novel synonymous mutation in the MPZ gene causing an aberrant splicing pattern and Charcot-Marie-Tooth disease type 1b.

Charcot-Marie-Tooth disease (CMT) is an inherited peripheral neuropathy with a heterogeneous genetic background. Here, we describe two CMT1B families with a mild sensory-motor neuropathy and a novel synonymous variant (c.309G > T, p.G103G) in exon 3 of the MPZ gene. Next generation sequencing analysis on a 94 CMT gene panel showed no mutations in other disease genes. In vitro splicing assay and mRNA expression analysis indicated that the c.309T variant enhances a cryptic donor splice site at position c.304 resulting in the markedly increased expression of the r.304_448del alternative transcript in patients' cells. This transcript is predicted to encode a truncated P0 protein (p.V102Cfs11*) lacking the transmembrane domain, thus suggesting a possible haploinsufficiency mechanism for this mutation. This is the third reported synonymous MPZ variant associated with CMT1 and affecting splicing. These data confirm the functional impact of synonymous variants on MPZ splicing and their possible role as disease-causing mutations rather than silent polymorphisms.

Variations of the perforin gene in patients with chronic inflammatory demyelinating polyradiculoneuropathy.

Perforin (PRF) has a key role in the function of cytotoxic T and natural killer cells. Rare variations of PRF1 predispose to autoimmunity. Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an autoimmune disease of the peripheral nervous system, involving defective lymphocyte apoptosis. The aim of this study was to investigate the role of PRF1 in CIDP. The entire coding region of PRF1 was sequenced in 94 patients and 158 controls. We found three missense variations leading to amino acid substitutions and one nonsense variation resulting in a premature stop codon. All variations would decrease PRF activity. Their overall frequency was significantly higher in patients than in controls (odds ratio (OR)=4.47). The most frequent variation was p.Ala91Val (OR=3.92) previously associated with other autoimmune diseases. Clinical analysis showed that PRF1 variations were more frequent in relapsing patients and in patients displaying axonal damage. These data suggest that PRF1 variations may influence CIDP development and course.

Peripheral nervous system involvement in Parkinson's disease: evidence and controversies.

BACKGROUND: In recent years, non-motor features of Parkinson's disease (PD) have received increasing attention and PD is currently considered a systemic rather than a pure basal ganglia disorder. Among the systemic features, peripheral neuropathy (PN) is a recent acquisition since the first case-control study reporting increased frequency of PN in PD dates back to 2008. METHODS: We reviewed available literature on peripheral nervous system (PNS) involvement in PD. RESULTS: Evidence of α-synuclein deposition in the PNS and small nerve fiber deterioration in both drug-naïve and treated PD patients is becoming stronger. In addition, several recent reports documented a significant role of levodopa exposure together with group B vitamin deficiency in facilitating the development of PN and case reports suggested that treatment with continuous levodopa intestinal infusion may increase the risk of acute PN compared to both oral levodopa and other dopaminergic treatments. CONCLUSION: It is currently debated whether PN is an intrinsic disease-related feature, a consequence of levodopa treatment or both. In this review, we will discuss the different hypotheses, as well as our perspective on open issues and controversies.

Validation of the Hamilton Rating Scale for Depression in adults with epilepsy.

PURPOSE: Mood disorders represent a frequent psychiatric comorbidity among patients with epilepsy, having a major impact on their quality of life and contributing considerably to the global burden of the disease. The availability of standardized clinical instruments validated in populations with epilepsy has important implications in terms of diagnosis and treatment. This aimed to validate the Hamilton Rating Scale for Depression (HRSD) in adult patients with epilepsy. METHODS: A consecutive sample of 120 adult outpatients with epilepsy was assessed using the Mini International Neuropsychiatric Inventory (MINI) Plus version 5.0.0 and the HRSD. RESULTS: Cronbach's alpha coefficient was 0.824 for the 17-item version and 0.833 for the 21-item version. Receiver operating characteristic analysis showed an area under the curve of 0.896 and 0.899, respectively, for the two versions. However, the HRSD-17 demonstrated the best psychometric properties compared to the HRSD-21 and, with a cutoff score of 6, showed a sensitivity of 94%, a specificity of 80%, a positive predictive value of 46%, and a negative predictive value of 99%. CONCLUSIONS: The HRSD proved to be reliable and valid in the epilepsy setting and will stimulate further research in this area.

Transorbital sonography in acute optic neuritis: a case-control study.

BACKGROUND AND PURPOSE: Acute unilateral optic neuritis is associated with a thickening of the retrobulbar portion of the optic nerve as revealed by transorbital sonography, but no comparison has been made between nerve sheath diameter and optic nerve diameter in patients with acute optic neuritis versus healthy controls. We evaluated optic nerve sheath diameter and optic nerve diameter in patients with acute optic neuritis and healthy controls and compared optic nerve sheath diameter and optic nerve diameter with visual-evoked potentials in patients. MATERIALS AND METHODS: A case-control study was performed in 2 centers. Twenty-one consecutive patients with onset of visual loss during the prior 10 days and established acute noncompressive unilateral optic neuritis were compared with 21 healthy controls, matched for sex and age (±5 years). Two experienced vascular sonographers performed the study by using B-mode transorbital sonography. Visual-evoked potentials were performed on the same day as the transorbital sonography and were evaluated by an expert neurophysiologist. Sonographers and the neurophysiologist were blinded to the status of the patient or control and to clinical information, including the side of the affected eye. RESULTS: The median optic nerve sheath diameter was thicker on the affected side (6.3 mm; interquartile range, 5.9-7.2 mm) compared with the nonaffected side (5.5 mm; interquartile range, 5.1-6.2 mm; P < .0001) and controls (5.2 mm; interquartile range, 4.8-5.5 mm; P < .0001). The median optic nerve diameter was 3.0 mm (range, 2.8-3.1 mm) on the affected side and 2.9 mm (range, 2.8-3.1 mm) on the nonaffected side (P = not significant.). Both sides were thicker than those in controls (2.7 mm; interquartile range, 2.5-2.8 mm; P = .001 and .009). No correlation was found between optic nerve sheath diameter and optic nerve diameter and amplitude and latency of visual-evoked potentials in patients with optic neuritis. CONCLUSIONS: Transorbital sonography is a promising tool to support the clinical diagnosis of acute optic neuritis. Further studies are needed to define its specific role in the diagnosis and follow-up of optic neuritis.

Revisiting the molecular mechanism of neurological manifestations in antiphospholipid syndrome: beyond vascular damage.

Antiphospholipid syndrome (APS) is a multiorgan disease often affecting the central nervous system (CNS). Typically, neurological manifestations of APS include thrombosis of cerebral vessels leading to stroke and requiring prompt initiation of treatment with antiplatelet drugs or anticoagulant therapy. In these cases, alterations of the coagulation system at various levels caused by multiple effects of antiphospholipid antibodies (aPL) have been postulated to explain the vascular damage to the CNS in APS. However, several nonvascular neurological manifestations of APS have progressively emerged over the past years. Nonthrombotic, immune-mediated mechanisms altering physiological basal ganglia function have been recently suggested to play a central role in the pathogenesis of these manifestations that include, among others, movement disorders such as chorea and behavioral and cognitive alterations. Similar clinical manifestations have been described in other autoimmune CNS diseases such as anti-NMDAR and anti-VGCK encephalitis, suggesting that the spectrum of immune-mediated basal ganglia disorders is expanding, possibly sharing some pathophysiological mechanisms. In this review, we will focus on thrombotic and nonthrombotic neurological manifestations of APS with particular attention to immune-mediated actions of aPL on the vascular system and the basal ganglia.

Prevalence and features of peripheral neuropathy in Parkinson's disease patients under different therapeutic regimens.

BACKGROUND: Recent reports suggest increased frequency of peripheral neuropathy (PN) in Parkinson's disease (PD) patients on levodopa compared with age-matched controls particularly during continuous levodopa delivery by intestinal infusion (CLDII). The aim of this study is to compare frequency, clinical features, and outcome of PN in PD patients undergoing different therapeutic regimens. METHODS: Three groups of consecutive PD patients, 50 on intestinal levodopa (CLDII), 50 on oral levodopa (O-LD) and 50 on other dopaminergic treatment (ODT), were enrolled in this study to assess frequency of PN using clinical and neurophysiological parameters. A biochemical study of all PN patients was performed. RESULTS: Frequency of PN of no evident cause was 28% in CLDII, 20% in O-LD, and 6% in ODT patients. Clinically, 71% of CLDII patients and all O-LD and ODT PN patients displayed a subacute sensory PN. In contrast, 29% of CLDII patients presented acute motor PN. Levodopa daily dose, vitamin B12 (VB12) and homocysteine (hcy) levels differed significantly in patients with PN compared to patients without PN. CONCLUSIONS: Our findings support the relationship between levodopa and PN and confirm that an imbalance in VB12/hcy may be a key pathogenic factor. We suggest two different, possibly overlapping mechanisms of PN in patients on CDLII: axonal degeneration due to vitamin deficiency and inflammatory damage. Whether inflammatory damage is triggered by vitamin deficiency and/or by modifications in the intestinal micro-environment should be further explored. Proper vitamin supplementation may prevent peripheral damage in most cases.

Non-invasive ventilation after surgery in amyotrophic lateral sclerosis.

BACKGROUND: Surgery in patients affected by amyotrophic lateral sclerosis (ALS) presents a particular anesthetic challenge because of the risk of post-operative pulmonary complications. AIMS OF THE STUDY: We report on the use of non-invasive ventilation (NIV) to prevent post-operative pulmonary complications (PPCs) in nine patients affected by ALS enrolled in a phase-1 clinical trial with stem cell transplantation. METHODS: All patients were treated with autologous mesenchymal stem cells implanted into the spinal cord with a surgical procedure. Anesthesia was induced with propofol and maintained with remifentanil and sevoflurane. No muscle relaxant was used. After awakening and regain of spontaneous breathing, patients were tracheally extubated. Non-invasive ventilation through nasal mask was delivered and non-invasive positive pressure ventilation and continuous positive pressure ventilation were started. RESULTS: The average time on NIV after surgery was 3 h and 12 min. All patients regained stable spontaneous breathing after NIV discontinuation and had no episodes of respiratory failure until the following day. CONCLUSIONS: Our case series suggest that the use of NIV after surgery can be a safe strategy to prevent PPCs in patients affected by ALS. The perioperative procedure we chose for these patients appeared safe even in patients with advanced functional stage of the disease.

Intermittent photic stimulation affects motor cortex excitability in photosensitive idiopathic generalized epilepsy.

PURPOSE: To assess the effect of intermittent photic stimulation (IPS) at a common activating frequency, i.e. 20Hz, on motor cortex excitability by means of transcranial magnetic stimulation (TMS) in photosensitive patients with idiopathic generalized epilepsy (IGE). METHODS: We studied 15 photosensitive IGE patients showing a photoparoxysmal response (PPR) to IPS at 20Hz. Nineteen normal subjects of similar age and sex acted as controls. After the resting motor threshold (rMT) was measured, we studied the corticomotor excitability in two conditions randomly delivered, during IPS (5s) at 20Hz and without IPS. Motor evoked potentials (MEPs) were recorded from the right first dorsal interosseous muscle (FDI). We determined the cortical silent period (cSP), the short-latency intracortical inhibition (SICI) at the interstimulus interval (ISI) of 3 and 4ms and the intracortical facilitation (ICF) at ISIs of 12 and 14ms. Data were analyzed by means of rmANOVAs. RESULTS: IPS at 20Hz is significantly shortening the cSP in normal subjects, while no significant changes were detected in patients. The rMT was significantly higher in patients than controls, as expected by the concurrent antiepileptic treatment. Other corticomotor excitability measures were unaffected. CONCLUSIONS: We confirm that IPS has a weak influence on the motor cortical output in patients with IGE and PPR. The loss of the normal shortening of the cSP, otherwise present in healthy subjects in response to IPS, may have a possible protective nature.