[Pathomechanism Underlying Intravenous Immunoglobulin Therapy for Chronic Inflammatory Demyelinating Polyneuropathy].

Considering its proven clinical usefulness and supportive evidence, intravenous immunoglobulin (IVIg) is used as first-line therapy for chronic inflammatory demyelinating polyneuropathy (CIDP) during the acute and chronic stages. However, the pathomechanism underlying IVIg administration for CIDP remains unclear. Autoantibodies, complement, inflammatory cytokines, chemokines, T cells, B cells, macrophages, and the blood-nerve barrier contribute to the onset and progress of CIDP. The mechanisms underlying the actions of IVIg in CIDP include the following: (1)neutralization of pathological autoantibodies by anti-idiotype antibodies, (2)inhibition of the neonatal Fc receptor (FcRn) with a consequent decrease in pathological autoantibodies, (3)neutralization of cytokines, chemokines, and complement, (4)activity modulation of T cells, B cells, and macrophages, and (5) recovery of blood-nerve barrier function. Compared with the management of typical CIDP, IVIg therapy is less effective for management of autoimmune nodopathy associated with anti-neurofascin-155 or contactin-1 IgG4 antibodies because (1)anti-idiotype antibodies associated with IVIg cannot effectively neutralize IgG4 owing to the strong antigen specificity of IgG4 autoantibodies, and (2)complement, T cells, and macrophages play an insignificant role in the pathomechanism of autoimmune nodopathy. Further understanding of the mechanisms underlying IVIg action and effectiveness of molecular targeted therapy, such as use of FcRn or complement inhibitors and the CD20 monoclonal antibody, is warranted to develop novel therapeutic strategies against CIDP.

[Peripheral neuroimmunological diseases - Neuropathological insights and clinical perspectives]. / Periphere neuroimmunologische Erkrankungen ­ neuropathologische Einsichten und klinische Perspektiven.

This article deals with peripheral neuroimmunological diseases and briefly outlines the currently most important aspects and treatment developments. Idiopathic inflammatory myopathies have different mechanisms of development, manifestations and prognoses. New classification systems and more specific treatment concepts have been developed. The IIMs include different subgroups. These entities can have specific autoantibodies. Diagnostically, a muscle biopsy is generally desirable for a precise diagnosis and is essential in unclear cases. Primary systemic vasculitides can be divided into different groups based on the predominant pattern of involvement, while secondary vasculitides and single organ vasculitides are also differentiated. Vasculitic myopathy cannot be equated with myositis and a reliable distinction is currently only possible by a muscle biopsy. Treatment concepts should be developed on an interdisciplinary basis. Chronic inflammatory demyelinating polyneuropathy is the most frequent immune-mediated neuropathy and is characterized by a predominant demyelination of the motor and sensory nerves. The disease course runs in phases or is progressive and leads to significant disability and reduction in quality of life, despite current standard treatment. Novel treatment approaches are currently undergoing clinical trials. Myasthenia gravis, with the leading symptom of exercise-induced muscle weakness, is caused by autoantibodies against structures of the neuromuscular endplate. Autoantibody testing is the most important pillar in the diagnosis and is now also increasingly guiding treatment decisions. Overall, peripheral neuroimmunological diseases represent a heterogeneous group. Increasing knowledge of the pathophysiology is the key to numerous developments in diagnostics and treatment, which could lead to far-reaching practical changes in the future.

[Immune-mediated neuropathies: pathophysiology and management].

Immune-mediated neuropathies (IMN) are a heterogenous group of disorders affecting the peripheral nervous system, due to dysregulation of the immune system. It mainly includes Guillain-Barre syndrome, chronic inflammatory demyelinating polyradiculoneuropathy, multifocal motor neuropathy and so on. Most of these diseases can be clinically improved by appropriate immunotherapy, but some patients still have unsatisfactory results. Therefore, studying the pathophysiology of the occurrence and development of diseases can reveal the nature of diseases and provide a theoretical basis for the prevention, diagnosis and treatment of diseases. In this paper, the pathophysiological mechanism of various IMNs is described in detail, with emphasis on immunological mechanism, and the progress of diagnosis and treatment of various IMNs is briefly introduced.

Usefulness of somatosensory evoked potentials for monitoring the clinical course of patients with chronic inflammatory demyelinating polyradiculoneuropathy.

INTRODUCTION/AIMS: Somatosensory evoked potentials (SSEPs) are described as a supportive tool to diagnose chronic inflammatory demyelinating polyradiculoneuropathy (CIDP); however, there is a lack of studies determining the effectiveness of SSEPs in monitoring the clinical course of individuals with this condition. The aims of this study are to evaluate the utility of SSEPs in monitoring patients with CIDP and to assess their association with clinical outcomes following immunomodulatory therapy. METHODS: This was a single-center retrospective observational study that included patients who met European Federation of Neurological Societies and Peripheral Nerve Society criteria for CIDP between 2018 and 2023. SSEPs were performed at diagnosis and during follow-up after the start of immunomodulatory treatment. Fisher's exact test was employed to assess the association between clinical improvement and SSEP improvement. RESULTS: Eighteen patients were included in the study. Ten patients had a typical CIDP pattern and 11 were male. In 17, SSEPs were abnormal prior to the start of immunomodulatory treatment. In patients who showed clinical improvement with immunomodulatory therapy, we observed that 15/17 had partial or complete improvement in SSEPs. Patients who showed no clinical improvement with first-line treatment exhibited worsening SSEPs. There was a significant association between clinical and SSEPs improvement (p = 0.009). DISCUSSION: We observed a positive association between improvement in SSEPs and clinical improvement in patients with CIDP. Our data suggest that SSEPs may be useful for monitoring the clinical course of patients with CIDP, but additional, larger studies are needed.

Hematopoietic stem cell transplantation (HSCT) for chronic inflammatory demyelinating polyradiculoneuropathy (CIDP): Is it CIDP?

Autologous hematopoietic stem cell transplantation (HSCT) is associated with 5-year treatment-free remissions in approximately 80% of patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) who failed or were dependent on intravenous immunoglobulin and or plasmapheresis. Autologous HSCT was associated with significant improvement in strength, independent ambulation, quality of life, nerve conduction velocity, and compound muscle action potential amplitude. The results of HSCT are dependent on proper patient selection, i.e., the right diagnosis and the right stage of the disease. An important caveat is that a significant number of patients with a CIDP diagnostic label are found upon further workup have a peripheral neuropathy of another etiology. Patients undergoing HSCT for CIDP should be reevaluated before HSCT to confirm the diagnosis and those who fail HSCT should be reevaluated for a diagnosis other than CIDP.

Preventing long-term disability in CIDP: the role of timely diagnosis and treatment monitoring in a multicenter CIDP cohort.

BACKGROUND: Chronic inflammatory demyelinating polyneuropathy (CIDP) is an inflammatory disease affecting the peripheral nerves and the most frequent autoimmune polyneuropathy. Given the lack of established biomarkers or risk factors for the development of CIDP and patients' treatment response, this research effort seeks to identify potential clinical factors that may influence disease progression and overall treatment efficacy. METHODS: In this multicenter, retrospective analysis, we have screened 197 CIDP patients who presented to the University Hospitals in Düsseldorf, Berlin, Cologne, Essen, Magdeburg and Munich between 2018 and 2022. We utilized the respective hospital information system and examined baseline data with clinical examination, medical letters, laboratory results, antibody status, nerve conduction studies, imaging and biopsy findings. Aside from clinical baseline data, we analyzed treatment outcomes using the Standard of Care (SOC) definition, as well as a comparison of an early (within the first 12 months after manifestation) versus late (more than 12 months after manifestation) onset of therapy. RESULTS: In terms of treatment, most patients received intravenous immunoglobulin (56%) or prednisolone (39%) as their first therapy. Patients who started their initial treatment later experienced a worsening disease course, as reflected by a significant deterioration in their Inflammatory Neuropathy Cause and Treatment (INCAT) leg disability score. SOC-refractory patients had worse clinical outcomes than SOC-responders. Associated factors for SOC-refractory status included the presence of fatigue as a symptom and alcohol dependence. CONCLUSION: Timely diagnosis, prompt initiation of treatment and careful monitoring of treatment response are essential for the prevention of long-term disability in CIDP and suggest a "hit hard and early" treatment paradigm.

Treatment response in patients with clinical and supportive laboratory features of chronic inflammatory demyelinating polyneuropathy without demyelinative findings on nerve conduction studies: A retrospective study.

INTRODUCTION/AIMS: Not all patients with chronic inflammatory demyelinating polyneuropathy (CIDP) have evidence of demyelination on nerve conduction studies (NCS). Patients with "supportive" evidence of CIDP on cerebrospinal fluid (CSF), magnetic resonance imaging (MRI), ultrasound (US), or nerve biopsy but not on NCS, often receive immunomodulating therapy. We evaluated the treatment response of patients with clinical and supportive features of CIDP lacking NCS evidence of demyelination. METHODS: Retrospective chart review was conducted on 232 patients who met CIDP clinical criteria and were treated with disease-modifying therapy. Patients included did not have NCS criteria of demyelination, but did have supportive CSF, MRI, or US findings consistent with CIDP. A positive treatment response was defined as at least a one-point improvement in the modified Rankin scale (mRS), or a four-point increase in the Medical Research Council sum score (MRCSS). RESULTS: Twenty patients met criteria: 17 of the 18 (94%) patients with CSF protein >45 mg/dL, 6 of the 14 (43%) with MRI lumbosacral root or plexus enhancement, and 4 of the 6 (67%) with enlarged proximal nerves on US. Eighteen patients received intravenous immunoglobulin, 10 corticosteroids, one plasma exchange, and six other immunomodulatory therapies. Twelve patients had a positive treatment response on the MRCSS or mRS. The presence of MRI lumbosacral root or plexus enhancement was associated with a positive treatment response. DISCUSSION: A trial of immunomodulating treatment should be considered for patients with clinical features of CIDP in the absence of NCS evidence of demyelination, particularly when there is MRI lumbosacral root or plexus enhancement.

Treatment response amplitude and timing in chronic inflammatory demyelinating polyneuropathy with routine care: Study of a UK cohort.

BACKGROUND AND PURPOSE: The amplitude, timing, and determinants of improvement with available treatments are uncertain in chronic inflammatory demyelinating polyneuropathy (CIDP). Our primary objective was to quantify categorized outcomes with routine care. METHODS: We retrospectively studied treatment response within 36 months from initiation in 112 consecutive subjects with CIDP. Response was classified into a proposed new "CIDP treatment-response category" (CT-RC), based on achieved endpoints. Determinants of the CT-RC, of timing of maximum improvement, and of treatment discontinuation were ascertained. RESULTS: The CT-RC demonstrated high concurrent validity with current outcome measures. Thirty-six subjects (32.1%) achieved a "complete response," 37 (33%) a "good partial response," 10 (8.9%) a "moderate partial response," and 15 (13.4%) a "poor partial response." Fourteen subjects (12.5%) were "nonresponsive." The CT-RC was independently predicted only by age. Mean time to maximum improvement was 12.1 months (range = 1-36) and was not associated with any pretreatment covariate. Treatment discontinuation occurred in 24 of 62 (38.2%) partial responders and was only associated with shorter pretreatment disease duration. Nonresponders were older and received a similar number of treatments compared to responders. CONCLUSIONS: CT-RC classification indicates persistent disability in >60% of treatment responders in CIDP. Timing of maximum improvement is variable, frequently delayed, and unpredictable. Treatment withdrawal without deterioration is achievable in approximately 40% of subjects and may be more likely with prompt treatment. Treatment withdrawal in partial responders and limited escalation in nonresponders suggest implication of physician- and patient-related factors in suboptimal response. More effective treatments/treatment methods and better understanding of other factors influencing response are needed in CIDP.

Subcutaneous immunoglobulins (SCIG) for chronic inflammatory demyelinating polyneuropathy (CIDP): A comprehensive systematic review of clinical studies and meta-analysis.

BACKGROUND: Chronic Inflammatory Demyelinating Polyneuropathy (CIDP) presents significant treatment challenges due to its chronic nature, varied clinical presentations, and rarity. Subcutaneous immunoglobulin (SCIG) has emerged as a maintenance therapy, offering potential advantages in administration and patient experience over the previously recognized intravenous immunoglobulin (IVIG). METHODS: We included all clinical studies involving CIDP patients treated with SCIG from eleven databases up to March 2024. RESULTS: 50 clinical studies were included in the systematic review, with 22 involved in the meta-analysis. These studies offer clinical data on around 1400 CIDP patients. Almost all studies considered SCIG a maintenance therapy, with the majority of results suggesting it as a viable substitute that may offer comparable or enhanced advantages. Studies covered aspects such as efficacy, safety, quality of life, practicality, economic evaluation, and patient preference. Meta-analysis showed SCIG significantly improved muscle strength and sensory function, had fewer and milder side effects, reduced relapse rates, and received a strong preference. CONCLUSIONS: Findings suggest that SCIG for CIDP maintenance not only provides a more feasible alternative, with economic evaluations showing considerable cost reductions over time, and patient preference for SCIG being pronounced, but may also deliver comparable or superior health outcomes. Ongoing research lines on formulations, techniques, and direct comparative studies are critical to further illuminate, enhance, and expand SCIG's role in treatment.

New chronic inflammatory demyelinating polyneuropathy/Guillain-Barré syndrome guidelines - impact on clinical practise.

PURPOSE OF REVIEW: There is no diagnostic biomarker that can reliably detect Guillain-Barré syndrome (GBS) or chronic inflammatory demyelinating polyneuropathy (CIDP). Diagnosis relies upon integrating key clinical characteristics and relevant supportive data. Consequently, misdiagnosis and delayed diagnosis are common. Diagnostic criteria have proven valuable resources to improve diagnosis, but are underutilized during routine clinical care. RECENT FINDINGS: In 2021, the EAN/PNS CIDP criteria was published, and were followed by the EAN/PNS GBS criteria in 2023. Both guidelines utilized GRADE methodology to formulate evidence-based recommendations that are intended to be used by adult and paediatric clinicians across diverse care settings to optimize diagnostic accuracy and improve patient outcomes during routine clinical care. SUMMARY: The EAN/PNS GBS and CIDP criteria detail specific clinical, electrophysiological, and laboratory features that raise diagnostic confidence, and call attention to diagnostic mimics. The sensitivity of EAN/PNS and other modern criteria to detect GBS and CIDP is high, but utilization during clinical practice is low. Complexity is one factor limiting widespread application. Strategies are needed to optimize criteria adoption during routine clinical care such that GBS and CIDP diagnosis can be achieved with greater speed and accuracy.

[Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP)]. / Chronische inflammatorische demyelinisierende Polyradikuloneuropathie (CIDP).

Chronic inflammatory demyelinating polyneuropathy (CIDP) is the most common chronic autoimmune disease of the peripheral nervous system. It is often difficult to diagnose, but severaly therapeutic options are nowadays available to reduce neurological deficits and to improve the disease course. This article exemplifies the management of CIDP by a typical case study.

Recurrent CNTN1 antibody-positive nodopathy: a case report and literature review.

Background: Contactin-1 (CNTN1) antibody-positive nodopathy is rare and exhibits distinct clinical symptoms such as tremors and ataxia. However, the mechanisms of these symptoms and the characteristics of the cerebral spinal fluid (CSF) remain unknown. Case presentation: Here, we report a case of recurrent CNTN1 antibody-positive nodopathy. Initially, a 45-year-old woman experiencing numbness in the upper limbs and weakness in the lower limbs was diagnosed with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). Eleven years later, her symptoms worsened, and she began to experience tremors and ataxia. Tests for serum CNTN1, GT1a, and GQ1b antibodies returned positive. Subsequently, she was diagnosed with CNTN1 antibody-positive nodopathy and underwent plasmapheresis therapy, although the treatment's efficacy was limited. To gain a deeper understanding of the disease, we conducted a comprehensive literature review, identifying 52 cases of CNTN1 antibody-positive nodopathy to date, with a tremor prevalence of 26.9%. Additionally, we found that the average CSF protein level in CNTN1 antibody-positive nodopathy was 2.57 g/L, with 87% of patients exhibiting a CSF protein level above 1.5 g/L. Conclusion: We present a rare case of recurrent CNTN1 antibody-positive nodopathy. Our findings indicate a high prevalence of tremor (26.9%) and elevated CSF protein levels among patients with CNTN1 antibody-positive nodopathy.

[Typical CIDP: Update of the Pathogenesis, Diagnosis, and Treatment].

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is the most common chronic immune-mediated demyelinating neuropathy and includes several clinical subtypes. The major phenotype is "typical CIDP," which is characterized by symmetric polyneuropathy and "proximal and distal" muscle weakness. In typical CIDP, the nerve roots and distal nerve terminals, where the blood-nerve barrier is anatomically deficient, are preferentially affected, and therefore antibody-mediated immune pathogenesis is likely to have a major role. Currently, CIDP is considered a syndrome including typical CIDP and CIDP variants. In 2021, the European Academy of Neurology/Peripheral Nerve Society Guideline was published, whereas the Japanese CIDP/ Multifocal Motor Neuropathy Clinical Practice Guideline will be available in May 2024. This review article summarizes the immunopathogenesis, diagnosis, and treatment for typical CIDP.

[Management of chronic inflammatory demyelinating polyradiculoneuropathy]. / Prise en charge de la polyradiculoneuropathie inflammatoire démyélinisante chronique.

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is the most common chronic autoimmune neuropathy. Its management has considerably evolved over the last decade. In 2021, the diagnostic guidelines for CIDP were updated and the diagnostic criteria simplified. They enable better characterization of the electro-clinical phenotype of the disease, and emphasize supportive criteria, in particular neuro-muscular imaging. In terms of pathophysiology, the discovery of antibodies directed against antigens in the nodal and paranodal regions has given rise to the concept of autoimmune nodopathy. Finally, the preliminary results of the ADHERE study on efgartigimod have rekindled hopes of a new, effective therapy for CIDP.

La polyradiculoneuropathie inflammatoire démyélinisante chronique (PIDC) est la neuropathie auto-immune chronique la plus fréquente. Sa prise en charge a largement évolué durant la dernière décennie. En 2021, les recommandations diagnostiques de la PIDC ont été mises à jour et les critères diagnostiques simplifiés. Ils permettent une meilleure caractérisation du phénotype électroclinique de la maladie et mettent en avant les critères de support diagnostiques, en particulier l'imagerie neuromusculaire. Sur le plan physiopathologique, la découverte d'anticorps dirigés contre des antigènes des régions nodale et paranodale a fait naître le concept de nodopathie auto-immune. Enfin, les résultats préliminaires de l'étude ADHERE sur l'efgartigimod font émerger l'espoir d'une nouvelle thérapie efficace dans la PIDC.

[Cutting edge of diagnosis and treatment for chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) based on the EAN/PNS guideline 2021].

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a most common chronic immune-mediated demyelinating neuropathy, and includes a number of clinical subtypes. The major phenotype is "typical CIDP", which is characterized by symmetric polyneuropathy and "proximal and distal" muscle weakness. During the historical changes in the concept of CIDP, multifocal motor neuropathy, anti-myelin-associated glycoprotein (MAG) neuropathy, and autoimmune nodopathy have been excluded. Currently CIDP is considered as a syndrome including typical CIDP and CIDP variant such as distal CIDP and multifocal CIDP. In 2021, the international guideline of diagnosis and treatment for CIDP, European Academy of Neurology (EAN)/Peripheral Nerve Society (PNS) Guideline, was published. This review article introduces the putline of the guideline with medical-social situation in Japan. The diagnosis of CIDP is based on (1) phenotype of typical CIDP or variant, (2) electrophysiologic evidence of peripheral nerve demyelination, and (3) exclusion criteria. The first-line treatments are corticosteroids or immunoglobulin therapy, and plasma exchange should be considered if the 2 treatments were not effective sufficiently. This guideline recommends intravenous or subcutaneous immunoglobulin as a maintenance therapy, and suggests other immune-suppressive agents. In the near future, new treatment with biologics, such as monoclonal antibodies against neonatal Fc receptors, complements, and CD19/20 will be approved.

Physician awareness and understanding of chronic inflammatory demyelinating polyradiculoneuropathy in Japan: a web-based study.

OBJECTIVES: To investigate potential knowledge gaps between neurologists and non-specialists and identify challenges in the current management of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), with a focus on 'early diagnosis' and 'appropriate treatment' for CIDP. DESIGN: A non-interventional, cross-sectional, web-based quantitative survey of physicians working in healthcare clinics or hospitals in Japan. SETTING: Participants were recruited from the Nikkei Business Publications panel from 18 August to 14 September 2022. PARTICIPANTS: Responses from 360 physicians (120 each of internists, orthopaedists and neurologists) were collected. OUTCOME MEASURES: Responses relating to a CIDP hypothetical case and current understanding were assessed to determine awareness, collaboration preferences and diagnosis and treatment decisions. RESULTS: Understanding of CIDP was 90.8% among neurologists, 10.8% among orthopaedists and 13.3% among internists; >80% of orthopaedists and internists answered that neurologists are preferable for treatment. Diagnostic assessment using a hypothetical case showed 95.0% of neurologists, 74.2% of orthopaedists and 72.5% of internists suspected CIDP. Among orthopaedists and internists suspecting CIDP, >70% considered referring to neurology, while ~10% considered continuing treatment without a referral. Among neurologists, 69.4% chose intravenous immunoglobulin (IVIg) as first-line treatment and determined effectiveness to be ≤3 months. CONCLUSIONS: Orthopaedists and internists had lower CIDP awareness compared with neurologists, which may lead to inadequate referrals to neurology. Evaluation of IVIg effectiveness for maintenance therapy occurred earlier than the guideline recommendations (6-12 months), risking premature discontinuation. Improving CIDP knowledge among orthopaedists and internists is critical for better diagnosis and collaboration with neurologists. Neurologists should consider slow and careful evaluation of IVIg maintenance therapy. TRIAL REGISTRATION NUMBER: UMIN000048516.

Anti-MAG neuropathy: historical aspects, clinical-pathological correlations, and considerations for future therapeutical trials.

BACKGROUND: Patients with anti-MAG neuropathy present with distal demyelinating polyneuropathy, IgM monoclonal gammopathy, and elevated titers of anti-MAG antibodies. OBJECTIVE: This paper reviews what is known about the clinical presentation, course, pathophysiology, and treatment of anti-MAG neuropathy, with considerations for the design of therapeutic trials. METHODS: A literature review of the medical and scientific literature related to anti-MAG neuropathy, and the design of therapeutic clinical trials in peripheral neuropathy. RESULTS: Anti-MAG neuropathy can remain indolent for many years but then enter a progressive phase. Highly elevated antibody titers are diagnostic, but intermediate titers can also occur in chronic inflammatory demyelinating polyneuropathy (CIDP). The peripheral nerves can become inexcitable, thereby masking the demyelinating abnormalities. There is good evidence that the anti-MAG antibodies cause neuropathy. Reduction of the autoantibody concentration by agents that target B-cells was reported to result in clinical improvement in case series and uncontrolled trials, but not in controlled clinical trials, probably due to inadequate trial design. CONCLUSION: We propose that therapeutic trials for anti-MAG neuropathy include patients with the typical presentation, some degree of weakness, highly elevated anti-MAG antibody titers, and at least one nerve exhibiting demyelinating range abnormalities. Treatment with one or a combination of anti-B-cell agents would aim at reducing the autoantibody concentration by at least 60%. A trial duration of 2 years may be required to show efficacy. The neuropathy impairment score of the lower extremities (NIS-LL) plus the Lower Limb Function (LLF) score would be a suitable primary outcome measure.

ANTECEDENTES: Pacientes com neuropatia anti-MAG apresentam polineuropatia desmielinizante distal, gamopatia monoclonal IgM e títulos elevados de anticorpos anti-MAG. OBJETIVO: Este artigo revisa o que se sabe sobre a apresentação clínica, curso, fisiopatologia e tratamento da neuropatia anti-MAG, com considerações para o desenho de ensaios terapêuticos. MéTODOS: Revisão bibliográfica da literatura médica e científica relacionada à neuropatia anti-MAG e desenho de ensaios clínicos terapêuticos em neuropatia periférica. RESULTADOS: A neuropatia anti-MAG pode permanecer indolente durante muitos anos, mas depois entra numa fase progressiva. Títulos de anticorpos altamente elevados são diagnósticos, mas títulos intermediários também podem ocorrer na polineuropatia desmielinizante inflamatória crônica (CIDP). Os nervos periféricos podem tornar-se inexcitáveis, mascarando, assim, as anomalias desmielinizantes. Há boas evidências de que os anticorpos anti-MAG causam a neuropatia. Foi relatado que a redução da concentração de autoanticorpos por agentes direcionados às células B resultou em melhora clínica em séries de casos e ensaios não controlados, mas não em ensaios clínicos controlados, provavelmente devido ao desenho inadequado dos ensaios. CONCLUSãO: Propomos que os ensaios terapêuticos para neuropatia anti-MAG incluam pacientes com apresentação típica, algum grau de fraqueza, títulos de anticorpos anti-MAG altamente elevados e pelo menos um nervo exibindo anormalidades na faixa desmielinizante. O tratamento com um ou uma combinação de agentes anticélulas B teria como objetivo reduzir a concentração de autoanticorpos em pelo menos 60%. Pode ser necessária uma duração de ensaio de 2 anos para demonstrar eficácia. A pontuação de comprometimento da neuropatia das extremidades inferiores (NIS-LL) mais a pontuação da função dos membros inferiores (LLF) seria uma medida de resultado primário adequada.

Prevalence, Clinical Profiles, and Prognosis of CIDP in Japanese Nationwide Survey: Analyses of 1,257 Diagnosis-Confirmed Patients.

BACKGROUND AND OBJECTIVES: To investigate the current epidemiology, clinical profile, and treatment of chronic inflammatory demyelinating polyneuropathy (CIDP) using a nationwide survey in Japan. METHODS: We conducted a nationwide survey using an epidemiologic method established in 2021. Questionnaire sheets were sent to the hospital departments of neurology and pediatric neurology throughout Japan. A primary questionnaire was used to determine the number of patients and their prevalence, and a second questionnaire was used to collect detailed clinical information. RESULTS: The primary survey showed that the estimated number of patients with CIDP was 4,180, with a prevalence of 3.3 per 100,000 persons. In the secondary survey, detailed clinical data were available for 1,257 patients. The male-to-female ratio was 1.5:1, and the median age at onset was 52 years. Typical CIDP was the most frequent subtype (52%), followed by distal (17%) and multifocal/focal CIDP (17%). Initial treatments included immunoglobulin therapy (72%), corticosteroids (15%), and others (13%). Among patients with CIDP, 78% had a progressive/relapsing course, 14% did not respond to first-line treatments, and 18% could not walk independently at the last visit. Among the subtypes, typical CIDP had the most severe disability before treatment (44% of patients could not walk independently). However, they showed a more favorable response to treatment than those with distal or multifocal CIDP. In the subgroup analyses, logistic regression analyses showed that younger age at onset, no muscle atrophy, and abnormal median-normal sural sensory nerve responses were associated with a higher probability of independent walking. DISCUSSION: Our study represents the largest cohort study on CIDP to demonstrate the current epidemiologic and clinical status of CIDP in Japan. Clinical subtypes seem to be associated with different treatment responses and outcomes; therefore, an appropriate treatment strategy according to the pathophysiology of each subtype is required to improve the prognosis of CIDP.