Hereditary transthyretin amyloidosis in middle-aged and elderly patients with idiopathic polyneuropathy: a nationwide prospective study.

BACKGROUND: Hereditary transthyretin amyloidosis (ATTRv) is an adult-onset autosomal dominant disease resulting from TTR gene pathogenic variants. ATTRv often presents as a progressive polyneuropathy, and effective ATTRv treatments are available. METHODS: In this 5 year-long (2017-2021) nationwide prospective study, we systematically analysed the TTR gene in French patients with age >50 years with a progressive idiopathic polyneuropathy. RESULTS: 553 patients (70% males) with a mean age of 70 years were included. A TTR gene pathogenic variant was found in 15 patients (2.7%), including the Val30Met TTR variation in 10 cases. In comparison with patients with no TTR gene pathogenic variants (n = 538), patients with TTR pathogenic variants more often presented with orthostatic hypotension (53 vs. 21%, p = .007), significant weight loss (33 vs 11%, p = .024) and rapidly deteriorating nerve conduction studies (26 vs. 8%, p = .03). ATTRv diagnosis led to amyloid cardiomyopathy diagnosis in 11 cases, ATTRv specific treatment in all cases and identification of 15 additional ATTRv cases among relatives. CONCLUSION: In this nationwide prospective study, we found ATTRv in 2.7% of patients with age >50 years with a progressive polyneuropathy. These results are highly important for the early identification of patients in need of disease-modifying treatments.

Usefulness and prognostic value of diagnostic tests in patients with possible chronic inflammatory demyelinating polyradiculoneuropathy.

INTRODUCTION/AIMS: Recent guidelines define chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and possible CIDP. The aims of our study were to evaluate the value of diagnostic tests to support the diagnosis of CIDP in patients with possible CIDP and to identify prognostic factors of therapeutic success. METHODS: We conducted an observational retrospective two-center study between 2014 and 2019. We selected patients with a clinical presentation suggesting CIDP, but whose electrodiagnostic (EDX) test results did not meet the EFNS/PNS 2021 criteria. We analyzed epidemiologic and clinical features, axonal loss on EDX, cerebrospinal fluid (CSF), somatosensory evoked potentials (SSEPs), plexus magnetic resonance imaging (MRI), nerve biopsy, and therapeutic response. RESULTS: We selected 75 patients, among whom 30 (40%) responded to treatment. The positivity rates of CSF analysis, MRI and SSEPs were not influenced by the clinical presentation or by the delay between symptom onset and medical assessment. A high protein level in CSF, female gender, and a relapsing-remitting course predicted the therapeutic response. DISCUSSION: It is important to properly diagnose suspected CIDP not meeting EFNS/PNS 2021 EDX criteria by using supportive criteria. Specific epidemiological factors and a raised CSF protein level predict a response to treatment. Further prospective studies are needed to improve diagnosis and the prognostic value of diagnostic tests in CIDP.

Prognostic Factors and Treatment Efficacy in Spinal Cord Sarcoidosis: An Observational Cohort With Long-term Follow-up.

BACKGROUND AND OBJECTIVES: Spinal cord sarcoidosis is a rare manifestation of sarcoidosis with a consequent risk of neurologic sequelae for the patient. We investigated prognostic factors and efficacy of immunosuppressive treatments in a longitudinal cohort. METHODS: We retrospectively studied patients with spinal cord sarcoidosis followed between 1995 and 2021 in 7 centers in France. Patients with definite, probable, or possible spinal cord sarcoidosis according to the Neurosarcoidosis Consortium Consensus Group criteria and with spinal cord involvement confirmed by MRI were included. We analyzed relapse or progression rate with a Poisson model, initial Rankin score with a linear model, and change in the Rankin score during follow-up with a logistic model. RESULTS: A total of 97 patients were followed for a median of 7.8 years. Overall mean relapse or progression rate was 0.17 per person-year and decreased over time. At last visit, 46 (47.4%) patients had a loss of autonomy (Rankin score ≥2). The main prognostic factors significantly associated with relapse or progression rate were gadolinium enhancement (relative rate [95% CI] 0.61 [0.4, 0.95]) or meningeal involvement (relative rate [95% CI] 2.05 [1.31, 3.19]) on spinal cord MRI and cell count (relative rate [95% CI] per 1 log increase 1.16 [1.01, 1.33]) on CSF analysis. Relapse or progression rate was not significantly associated with initial Rankin score or Expanded Disability Status Scale. Tumor necrosis factor-α (TNF-α) antagonists significantly decreased relapse or progression rate compared with corticosteroids alone (relative rate [95% CI] 0.33 [0.11, 0.98]). Azathioprine was significantly less effective than methotrexate on relapse or progression rate (relative rate [95% CI] 2.83 [1.04, 7.75]) and change in Rankin score (mean difference [95% CI] 0.65 [0.23, 1.08]). DISCUSSION: Regarding the relapse or progression rate, meningeal localization of sarcoidosis was associated with a worse prognosis, TNF-α antagonists resulted in a significant decrease compared to corticosteroids alone, and methotrexate was more effective than azathioprine. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that in individuals with spinal cord neurosarcoidosis, TNF-α antagonists were associated with decreased relapse or progression rate compared to corticosteroids alone, but other therapies showed no significant benefit.

Risk Factors and Time to Clinical Symptoms of Multiple Sclerosis Among Patients With Radiologically Isolated Syndrome.

Importance: Younger age, oligoclonal bands, and infratentorial and spinal cord lesions are factors associated with an increased 10-year risk of clinical conversion from radiologically isolated syndrome (RIS) to multiple sclerosis (MS). Whether disease-modifying therapy is beneficial for individuals with RIS is currently unknown. Objectives: To evaluate the 2-year risk of a clinical event (onset of clinical symptoms of MS) prospectively, identify factors associated with developing an early clinical event, and simulate the sample size needed for a phase III clinical trial of individuals with RIS meeting 2009 RIS criteria. Design, Setting, and Participants: This cohort study used data on prospectively followed-up individuals with RIS identified at 1 of 26 tertiary centers for MS care in France that collect data for the Observatoire Français de la Sclérose en Plaques database. Participants were aged 10 to 80 years with 2 or more magnetic resonance imaging (MRI) scans after study entry and an index scan after 2000. All diagnoses were validated by an expert group, whose review included a double centralized MRI reading. Data were analyzed from July 2020 to January 2021. Exposure: Diagnosis of RIS. Main Outcomes and Measures: Risk of clinical event and associated covariates at index scan were analyzed among all individuals with RIS. Time to the first clinical event was compared by covariates, and sample size estimates were modeled based on identified risk factors. Results: Among 372 individuals with RIS (mean [SD] age at index MRI scan, 38.6 [12.1] years), 354 individuals were included in the analysis (264 [74.6%] women). A clinical event was identified among 49 patients (13.8%) within 2 years, which was associated with an estimated risk of conversion of 19.2% (95% CI, 14.1%-24.0%). In multivariate analysis, age younger than 37 years (hazard ratio [HR], 4.04 [95% CI, 2.00-8.15]; P < .001), spinal cord lesions (HR, 5.11 [95% CI, 1.99-13.13]; P = .001), and gadolinium-enhancing lesions on index scan (HR, 2.09 [95% CI, 1.13-3.87]; P = .02) were independently associated with an increased risk of conversion to MS. Having 2 factors at the time of the index MRI scan was associated with a risk of 27.9% (95% CI, 13.5%-39.9%) of a seminal event within 2 years, increasing to 90.9% (95% CI, 41.1%-98.6%) for individuals with all 3 factors (3 risk factors vs none: HR, 23.34 [95% CI, 9.08-59.96]; P < .001). Overall, with 80% power to detect an effect size of 60% within 24 months, a total of 160 individuals with RIS were needed assuming an event rate of 20%. Conclusions and Relevance: This study found that age younger than age 37 years, spinal cord involvement, and gadolinium-enhancing lesions on index MRI scan were associated with earlier clinical disease and relevant to the number of enrolled patients needed to detect a potential treatment effect.

Argonaute Autoantibodies as Biomarkers in Autoimmune Neurologic Diseases.

OBJECTIVE: To identify and characterize autoantibodies (Abs) as novel biomarkers for an autoimmune context in patients with central and peripheral neurologic diseases. METHODS: Two distinct approaches (immunoprecipitation/mass spectrometry-based proteomics and protein microarrays) and patients' sera and CSF were used. The specificity of the identified target was confirmed by cell-based assay (CBA) in 856 control samples. RESULTS: Using the 2 methods as well as sera and CSF of patients with central and peripheral neurologic involvement, we identified Abs against the family of Argonaute proteins (mainly AGO1 and AGO2), which were already reported in systemic autoimmunity. AGO-Abs were mostly of immunoglobulin G 1 subclass and conformation dependent. Using CBA, AGO-Abs were detected in 21 patients with a high suspicion of autoimmune neurologic diseases (71.4% were women; median age 57 years) and only in 4/856 (0.5%) controls analyzed by CBA (1 diagnosed with small-cell lung cancer and the other 3 with Sjögren syndrome). Among the 21 neurologic patients identified, the main clinical presentations were sensory neuronopathy (8/21, 38.1%) and limbic encephalitis (6/21, 28.6%). Fourteen patients (66.7%) had autoimmune comorbidities and/or co-occurring Abs, whereas AGO-Abs were the only autoimmune biomarker for the remaining 7/21 (33.3%). Thirteen (61.9%) patients were treated with immunotherapy; 8/13 (61.5%) improved, and 3/13 (23.1%) remained stable, suggesting an efficacy of these treatments. CONCLUSIONS: AGO-Abs might be potential biomarkers of autoimmunity in patients with central and peripheral nonparaneoplastic neurologic diseases. In 7 patients, AGO-Abs were the only biomarkers; thus, their identification may be useful to suspect the autoimmune character of the neurologic disorder. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that AGO-Abs are more frequent in patients with autoimmune neurologic diseases than controls.

TNF-α inhibitors used as steroid-sparing maintenance monotherapy in parenchymal CNS sarcoidosis.

OBJECTIVE: To assess the efficacy of tumour necrosis factor-α (TNF-α) inhibitors used as steroid-sparing monotherapy in central nervous system (CNS) parenchymal sarcoidosis. METHODS: The French Multiple Sclerosis and Neuroinflammation Centers retrospectively identified patients with definite or probable CNS sarcoidosis treated with TNF-α inhibitors as steroid-sparing monotherapy. Only patients with CNS parenchymal involvement demonstrated by MRI and imaging follow-up were included. The primary outcome was the minimum dose of steroids reached that was not associated with clinical or imaging worsening during a minimum of 3 months after dosing change. RESULTS: Of the identified 38 patients with CNS sarcoidosis treated with TNF-α inhibitors, 23 fulfilled all criteria (13 females). Treatments were infliximab (n=22) or adalimumab (n=1) for a median (IQR) of 24 (17-40) months. At treatment initiation, the mean (SD) age was 41.5 (10.5) years and median (IQR) disease duration 22 (14-49.5) months. Overall, 60% of patients received other immunosuppressive agents before a TNF-α inhibitor. The mean (SD) minimum dose of steroids was 31.5 (33) mg before TNF-α inhibitor initiation and 6.5 (5.5) mg after (p=0.001). In all, 65% of patients achieved steroids dosing <6 mg/day; 61% showed clinical improvement, 30% stability and 9% disease worsening. Imaging revealed improvement in 74% of patients and stability in 26%. CONCLUSION: TNF-α inhibitors can greatly reduce steroids dosing in patients with CNS parenchymal sarcoidosis, even refractory. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that TNF-α inhibitor used as steroid-sparing monotherapy is effective for patients with CNS parenchymal sarcoidosis.

Untreated patients with multiple sclerosis: A study of French expert centers.

BACKGROUND AND PURPOSE: Disease-modifying therapies (DMTs) have an impact on relapses and disease progression. Nonetheless, many patients with multiple sclerosis (MS) remain untreated. The objectives of the present study were to determine the proportion of untreated patients with MS followed in expert centers in France and to determine the predictive factors of nontreatment. METHODS: We conducted a retrospective cohort study. Data were extracted from the 38 centers participating in the European Database for Multiple Sclerosis (EDMUS) on December 15, 2018, and patients with MS seen at least once during the study period (from June 15, 2016 to June 14, 2017) were included. RESULTS: Of the 21,189 patients with MS (age 47.1 ± 13.1 years; Expanded Disability Status Scale (EDSS) score 3.4 ± 2.4), 6,631 (31.3%; 95% confidence interval [CI] 30.7-31.9) were not receiving any DMT. Although patients with a relapsing-remitting course (n = 11,693) were the most likely to receive DMT, 14.8% (95% CI 14.2-15.4) were still untreated (6.8% never treated). After multivariate analysis among patients with relapsing-remitting MS, the main factors explaining never having been treated were: not having ≥9 lesions on brain magnetic resonance imaging (odds ratio [OR] 0.52 [95% CI 0.44-0.61]) and lower EDSS score (OR 0.78 [95% CI 0.74-0.82]). Most patients with progressive MS (50.4% for secondary and 64.2% for primary progressive MS) did not receive any DMT during the study period, while 11.6% of patients with secondary and 34.0% of patients with primary progressive MS had never received any DMT. CONCLUSION: A significant proportion of patients with MS did not receive any DMT, even though such treatments are reimbursed by the healthcare system for French patients. This result highlights the unmet need for current DMTs for a large subgroup of patients with MS.

Effect of familial clustering in the genetic screening of 235 French ALS families.

OBJECTIVES: To determine whether the familial clustering of amyotrophic lateral sclerosis (ALS) cases and the phenotype of the disease may help identify the pathogenic genes involved. METHODS: We conducted a targeted next-generation sequencing analysis on 235 French familial ALS (FALS), unrelated probands to identify mutations in 30 genes linked to the disease. The genealogy, that is, number of cases and generations with ALS, gender, age, site of onset and the duration of the disease were analysed. RESULTS: Regarding the number of generations, 49 pedigrees had only one affected generation, 152 had two affected generations and 34 had at least three affected generations. Among the 149 pedigrees (63.4%) for which a deleterious variant was found, an abnormal G4C2 expansion in C9orf72 was found in 98 cases as well as SOD1, TARBP or FUS mutations in 30, 9 and 7 cases, respectively. Considering pedigrees from the number of generations, abnormal G4C2 expansion in C9orf72 was more frequent in pedigrees with pairs of affected ALS cases, which represented 65.2% of our cohort. SOD1 mutation involved all types of pedigrees. No TARDBP nor FUS mutation was present in monogenerational pedigrees. TARDBP mutation predominated in bigenerational pedigrees with at least three cases and FUS mutation in multigenerational pedigrees with more than seven cases, on average, and with an age of onset younger than 45 years. CONCLUSION: Our results suggest that familial clustering, phenotypes and genotypes are interconnected in FALS, and thus it might be possible to target the genetic screening from the familial architecture and the phenotype of ALS cases.

Paraneoplastic subacute sensory neuropathy with triple positive antineuronal antibodies associated with small-cell lung cancer.

A 67-year-old woman with a history of smoking and cardiovascular risk factors was admitted to the emergency room for uncontrolled diabetes, loss of appetite, nausea, significant weight loss and asthenia. The initial investigation, including cerebral and gastrointestinal explorations, were normal. One month later, she started presenting severe asymmetric proprioceptive ataxia of the lower extremities. She also reported paresthesia and neuropathic pain in both feet and ankles. A positron emission tomography (PET)-scanner showed a hypermetabolic nodule in the right lung. The neurological symptoms were attributed to paraneoplastic sensory and dysautonomic neuropathy, even though the bronchoscopic biopsies came back negative at first. Anti-Hu, anti-CV2/CRMP5 and anti-SOX1 antibodies were documented. Due to the severity and rapid progression of symptoms (from the lower to the upper limbs), corticosteroids, intravenous immunoglobulins and immunosuppressants were introduced prior to biopsies revealing a small-cell lung cancer. Despite these treatments and antineoplastic chemotherapy, her status deteriorated rapidly.

Progressive Multifocal Leukoencephalopathy Incidence and Risk Stratification Among Natalizumab Users in France.

Importance: Risk of developing progressive multifocal leukoencephalopathy (PML) is the major barrier to using natalizumab for patients with multiple sclerosis (MS). To date, the association of risk stratification with PML incidence has not been evaluated. Objective: To describe the temporal evolution of PML incidence in France before and after introduction of risk minimization recommendations in 2013. Design, Setting, and Participants: This observational study used data in the MS registry OFSEP (Observatoire Français de la Sclérose en Plaques) collected between April 15, 2007, and December 31, 2016, by participating MS expert centers and MS-dedicated networks of neurologists in France. Patients with an MS diagnosis according to current criteria, regardless of age, were eligible, and those exposed to at least 1 natalizumab infusion (n = 6318) were included in the at-risk population. A questionnaire was sent to all centers, asking for a description of their practice regarding PML risk stratification. Data were analyzed in July 2018. Exposures: Time from the first natalizumab infusion to the occurrence of PML, natalizumab discontinuation plus 6 months, or the last clinical evaluation. Main Outcomes and Measures: Incidence was the number of PML cases reported relative to the person-years exposed to natalizumab. A Poisson regression model for the 2007 to 2016 period estimated the annual variation in incidence and incidence rate ratio (IRR), adjusted for sex and age at treatment initiation and stratified by period (2007-2013 and 2013-2016). Results: In total, 6318 patients were exposed to natalizumab during the study period, of whom 4682 (74.1%) were female, with a mean (SD [range]) age at MS onset of 28.5 (9.1 [1.1-72.4]) years; 45 confirmed incident cases of PML were diagnosed in 22 414 person-years of exposure. The crude incidence rate for the whole 2007 to 2016 period was 2.00 (95% CI, 1.46-2.69) per 1000 patient-years. Incidence significantly increased by 45.3% (IRR, 1.45; 95% CI, 1.15-1.83; P = .001) each year before 2013 and decreased by 23.0% (IRR, 0.77; 95% CI, 0.61-0.97; P = .03) each year from 2013 to 2016. Conclusions and Relevance: The results of this study suggest, for the first time, a decrease in natalizumab-associated PML incidence since 2013 in France that may be associated with a generalized use of John Cunningham virus serologic test results; this finding appears to support the continuation and reinforcement of educational activities and risk-minimization strategies in the management of disease-modifying therapies for multiple sclerosis.

CLIPPERS and its mimics: evaluation of new criteria for the diagnosis of CLIPPERS.

OBJECTIVE: To evaluate the accuracy of the recently proposed diagnostic criteria for chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS). METHODS: We enrolled 42 patients with hindbrain punctate and/or linear enhancements (<3 mm in diameter) and tested the CLIPPERS criteria. RESULTS: After a median follow-up of 50 months (IQR 25-82), 13 out of 42 patients were CLIPPERS-mimics: systemic and central nervous system lymphomas (n=7), primary central nervous system angiitis (n=4) and autoimmune gliopathies (n=2). The sensitivity and specificity of the CLIPPERS criteria were 93% and 69%, respectively. Nodular enhancement ( ≥ 3 mm in diameter), considered as a red flag in CLIPPERS criteria, was present in 4 out of 13 CLIPPERS-mimics but also in 2 out of 29 patients with CLIPPERS, explaining the lack of sensitivity. Four out of 13 CLIPPERS-mimics who initially met the CLIPPERS criteria displayed red flags at the second attack with a median time of 5.5 months (min 3, max 18), explaining the lack of specificity. One of these four patients had antimyelin oligodendrocyte glycoprotein antibodies, and the three remaining patients relapsed despite a daily dose of prednisone/prednisolone ≥ 30 mg and a biopsy targeting atypical enhancing lesions revealed a lymphoma. CONCLUSIONS: Our study highlights that (1) nodular enhancement should be considered more as an unusual finding than a red flag excluding the diagnosis of CLIPPERS; (2) red flags may occur up to 18 months after disease onset; (3) as opposed to CLIPPERS-mimics, no relapse occurs when the daily dose of prednisone/prednisolone is ≥ 30 mg; and (4) brain biopsy should target an atypical enhancing lesion when non-invasive investigations remain inconclusive.

N-hexane exposure: a cause of small fiber neuropathy.

A 59-year-old woman presented with progressive paresthesias of all of her limbs for 4 years, associated with neuropathic pain, tingling in the tongue and allodynia, consistent with small fiber neuropathy (SFN). Several systemic symptoms and signs were found on clinical examination and laboratory work-up. Neurological investigations including neurophysiologic test and skin biopsy supported the diagnosis of SFN. Chronic exposure to N-hexane was then disclosed and suspected to be the cause of the disease. Following the discontinuation of chronic N-hexane exposure, the patient had a progressive improvement of all signs and symptoms, reinforcing the correlation between exposure to N-hexane, and development of SFN. Exposure to N-hexane may be considered as a novel reversible cause of SFN, which underlines the need to look for toxic etiologies in the diagnosis of SFN.

Paraneoplastic neuropathies.

PURPOSE OF REVIEW: To review recent advances in paraneoplastic neuropathies with emphasis on their definition, different forms and therapeutic development. RECENT FINDINGS: A strict definition of definite paraneoplastic neuropathies is necessary to avoid confusion. With carcinoma, seronegative sensory neuronopathies and neuronopathies and anti-Hu and anti-CV2/Contactin Response Mediator Protein 5 antibodies are the most frequent. With lymphomas, most neuropathies occur with monoclonal gammopathy including AL amyloidosis, Polyneuropathy-Organomegaly-Endocrinopathy-M component-Skin changes (POEMS) syndrome, type I cryoglobulinemia and antimyelin-associated glycoprotein (MAG) neuropathies and Waldenström's disease. Neuropathies improving with tumor treatment are occasional, occur with a variety of cancer and include motor neuron disease, chronic inflammatory demyelinating neuropathy and nerve vasculitis. If antibodies toward intracellular antigens are well characterized, it is not the case for antibodies toward cell membrane proteins. Contactin-associated protein-2 antibodies occur with neuromyotonia and thymoma with the Morvan's syndrome in addition to Netrin 1 receptor antibodies but may not be responsible for peripheral nerve hyperexcitability. The treatment of AL amyloidosis, POEMS syndrome, anti-MAG neuropathy and cryoglobulinemia is now relatively well established. It is not the case with onconeural antibodies for which the rarity of the disorders and a short therapeutic window are limiting factors for the development of clinical trials. SUMMARY: A strict definition of paraneoplastic neuropathies helps their identification and is necessary to allow an early diagnosis of the underlying tumor.

Unusual association of amyotrophic lateral sclerosis and myasthenia gravis: A dysregulation of the adaptive immune system?

Myasthenia gravis is an autoimmune disorder affecting neuromuscular junctions that has been associated with a small increased risk of amyotrophic lateral sclerosis (ALS). Here, we describe a retrospective series of seven cases with a concomitant diagnosis of ALS and myasthenia gravis, collected among the 18 French reference centers for ALS in a twelve year period. After careful review, only six patients strictly met the diagnostic criteria for both ALS and myasthenia gravis. In these patients, limb onset of ALS was reported in five (83%) cases. Localization of myasthenia gravis initial symptoms was ocular in three (50%) cases, generalized in two (33%) and bulbar in one (17%). Median delay between onset of the two conditions was 19 months (6-319 months). Anti-acetylcholine receptor antibodies testing was positive in all cases. All patients were treated with riluzole and one had an associated immune-mediated disease. In the one last ALS case, the final diagnosis was false-positivity for anti-acetylcholine receptor antibodies. The co-occurrence of ALS and myasthenia gravis is rare and requires strict diagnostic criteria. Its demonstration needs thoughtful interpretation of electrophysiological results and exclusion of false positivity for myasthenia gravis antibody testing in some ALS cases. This association may be triggered by a dysfunction of adaptive immunity.

Clinical features and prognostic factors of spinal cord sarcoidosis: a multicenter observational study of 20 BIOPSY-PROVEN patients.

Sarcoidosis of the spinal cord is a rare disease. The aims of this study are to describe the features of spinal cord sarcoidosis (SCS) and identify prognostic markers. We analyzed 20 patients over a 20-year period in 8 French hospitals. There were 12 men (60 %), mostly Caucasian (75 %). The median ages at diagnosis of sarcoidosis and myelitis were 34.5 and 37 years, respectively. SCS revealed sarcoidosis in 12 patients (60 %). Eleven patients presented with motor deficit (55 %) and 9 had sphincter dysfunction (45 %). The median initial Edmus Grading Scale (EGS) score was 2.5. The cerebrospinal fluid (CSF) showed elevated protein level (median: 1.00 g/L, interquartile range (IQR) 0.72-1.97), low glucose level (median 2.84 mmol/L, IQR 1.42-3.45), and elevated white cell count (median 22/mm(3), IQR 6-45). The cervical and thoracic cords were most often affected (90 %). All patients received steroids and an immunosuppressive drug was added in 10 cases (50 %). After a mean follow-up of 52.1 months (range 8-43), 18 patients had partial response (90 %), 7 displayed functional impairment (35 %), and the median final EGS score was 1. Six patients experienced relapse (30 %). There was an association between the initial and the final EGS scores (p = 0.006). High CSF protein level showed a trend toward an association with relapse (p = 0.076). The spinal cord lesion was often the presenting feature of sarcoidosis. Most patients experienced clinical improvement with corticosteroids and/or immunosuppressive treatment. The long-term functional prognosis was correlated with the initial severity.

Identifying a therapeutic window in acute and subacute inflammatory sensory neuronopathies.

BACKGROUND: Patients with inflammatory sensory neuronopathy (SNN) may benefit from immunomodulatory or immunosuppressant treatments if administered timely. Knowing the temporal profile of neuronal loss in dorsal root ganglia will help to ascertain whether a final diagnosis may be reached before the occurrence of irreversible neuronal injuries. Thus, we addressed the evolution of neuronal loss in SNN by using sensory nerve action potentials (SNAPs) as a surrogate marker of neuron degeneration. METHODS: Eighty-six patients with acute/subacute inflammatory SNN (paraneoplastic, associated with dysimmune diseases, or idiopathic) were retrospectively studied. The monthly SNAP reduction was determined and normalized with the lower limit of normal. Disability progression was expressed by the modified Rankin score and correlated with SNAP reduction. RESULTS: The monthly SNAP reduction was similar in the four limbs although the median nerve was less severely affected. The monthly SNAP reduction was very severe within the first two months of evolution, began to slow down after seven months, and stabilized after ten months. It was tightly correlated with disability progression. Kaplan-Meier analysis showed that the median time until matching the diagnostic criteria of SNN was 8.5 months. Within this period, 42% of nerves remained excitable. CONCLUSIONS: Developing treatment aiming at the stabilization of SNN is possible within the first 8 months of evolution. An improvement of the disease is possible if patients are treated within two months, which needs an early referral to an expert center and ENMG testing of the radial and ulnar nerves, which are most sensitive to changes.

Vincristine-induced neuropathy: Atypical electrophysiological patterns in children.

INTRODUCTION: Vincristine is an antimitotic agent used for treatment of leukemia, lymphomas, and cancers. Its main side effect is a dose-related, length-dependent (LD) axonal neuropathy. METHODS: We performed electrodiagnostic (EDx) examinations in 17 children who had been treated with vincristine and who presented with the clinical picture of a peripheral neuropathy. RESULTS: The mean dose of vincristine was 8.5 ± 4.0 mg/m(2) . Clinical motor symptoms were more frequent and more severe than sensory ones. Thirteen children presented with a motor deficit, 4 of whom could no longer walk. EDx examination showed an axonal neuropathy with a non-length-dependent (NLD) pattern in 9 children and an LD pattern in 8. A major motor predominance was encountered in 12 patients. CONCLUSIONS: The electrophysiological and clinical motor predominance described differs from the mainly sensory neuropathy reported in adults. Incomplete myelination due to young age may have resulted in greater sensitivity of some nerves to neurotoxic agents.

Is there a paraneoplastic ALS?

Our objective was to examine the strength of evidence in support of the paraneoplastic syndrome (PNS) as one cause of ALS and, if the association appears more likely than chance, determine which features of ALS imply concurrent malignancy. We reviewed the literature on concurrent ALS and neoplasia assessing the strength of evidence for the association. Most accounts of ALS and neoplasm are case reports or small uncontrolled series. In order of strength of evidence, three clinical situations that support a paraneoplastic aetiology for ALS are: 1) laboratory evidence of well-characterized onconeuronal antibodies, most often anti-Hu, anti-Yo or anti-Ri; 2) co-occurrence of ALS and a neoplasm known to cause PNS, usually lymphoma or cancer of the breast; and 3) combined ALS and a neoplasm not classically associated with PNS, without detectable onconeuronal antibodies. Clinical features that warrant evaluation of neoplasm include upper motor neuron disease in elderly females, rapid progression, non-motor signs, and young onset. In conclusion, most examples of ALS and neoplasm do not constitute a classically established PNS. Rare instances of elevated onconeuronal antibody titres or typical neoplasm, implies that, albeit rare, the PNS is one of a multitude of causes of ALS.