Evaluation of diagnostic yield of the 2021 European Academy of Neurology/Peripheral Nerve Society diagnostic criteria for CIDP.

INTRODUCTION/AIMS: It is unclear whether the revised European Academy of Neurology/Peripheral Nerve Society diagnostic criteria (EAN/PNS 2021 criteria) improved the diagnostic yield for chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) compared with the previous version. Therefore, this study aimed to compare the sensitivity and specificity of the EAN/PNS 2021 criteria and the European Federation of Neurological Societies/Peripheral Nerve Society 2010 diagnostic criteria (EFNS/PNS 2010 criteria), with a specific focus on the electrodiagnostic criteria. METHODS: Data of patients with clinically suspected CIDP who exhibited objective treatment response, and of those with chronic axonal neuropathies, obtained between 2009 and 2021, were extracted retrospectively from our database. Patients who underwent nerve conduction studies in at least unilateral upper and lower extremities were enrolled. We compared the sensitivity and specificity of the EAN/PNS 2021 and EFNS/PNS 2010 criteria. RESULTS: In total, 55 patients with clinically suspected CIDP and 36 patients with chronic axonal neuropathies were enrolled. When considering the "possible CIDP" category, the EAN/PNS 2021 criteria showed lower sensitivity than the EFNS/PNS 2010 criteria (78% vs. 93%, p < .05), whereas its specificity was higher (78% vs. 61%, p < .05). The lower sensitivity was caused mainly by the failure to fulfill the sensory nerve conduction criteria. The revised definition of abnormal temporal dispersion of the tibial nerve contributed markedly to the improved specificity. DISCUSSION: To improve the sensitivity of the EAN/PNS 2021 criteria, increasing the number of tested sensory nerves may be necessary.

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.

The difference in nerve ultrasound and motor nerve conduction studies between autoimmune nodopathy and chronic inflammatory demyelinating polyneuropathy.

INTRODUCTION/AIMS: Nerve enlargement has been described in autoimmune nodopathy and chronic inflammatory demyelinating polyneuropathy (CIDP). However, comparisons of the distribution of enlargement between autoimmune nodopathy and CIDP have not been well characterized. To fill this gap, we explored differences in the ultrasonographic and electrophysiological features between autoimmune nodopathy and CIDP. METHODS: Between March 2015 and June 2023, patients fulfilling diagnostic criteria for CIDP were enrolled; among them, those with positive antibodies against nodal-paranodal cell-adhesion molecules were distinguished as autoimmune nodopathy. Nerve ultrasound and nerve conduction studies (NCS) were performed. RESULTS: Overall, 114 CIDP patients and 13 patients with autoimmune nodopathy were recruited. Cross-sectional areas (CSA) at all sites were larger in patients with CIDP and autoimmune nodopathy than in healthy controls. CSAs at the roots and trunks of the brachial plexus were significantly larger in patients with anti-neurofascin-155 (NF155), anti-contactin-1 (CNTN1), and anti-contactin-associated protein 1 (CASPR1) antibodies than in CIDP patients. The patients with anti-NF186 antibody did not have enlargement in the brachial plexus. NCS showed more frequent probable conduction block at Erb's point in autoimmune nodopathy than in CIDP (61.9% vs. 36.6% for median nerve, 52.4% vs. 39.5% for ulnar nerve). Markedly prolonged distal motor latencies were also present in autoimmune nodopathy. DISCUSSION: Patients with autoimmune nodopathies had distinct distributions of peripheral nerve enlargement revealed by ultrasound, as well as distinct NCS patterns, which were different from CIDP. This suggests the potential utility of nerve ultrasound and NCS to supplement clinical characteristics for distinguishing nodopathies from CIDP.

Impact of 2021 European Academy of Neurology/Peripheral Nerve Society diagnostic criteria on diagnosis and therapy of chronic inflammatory demyelinating polyradiculoneuropathy variants.

BACKGROUND AND PURPOSE: There are different criteria for the diagnosis of different variants of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). The 2021 European Academy of Neurology/Peripheral Nerve Society (EAN/PNS) guidelines provide specific clinical criteria for each CIDP variant even if their therapeutical impact has not been investigated. METHODS: We applied the clinical criteria for CIDP variants of the 2021 EAN/PNS guidelines to 369 patients included in the Italian CIDP database who fulfilled the 2021 EAN/PNS electrodiagnostic criteria for CIDP. RESULTS: According to the 2021 EAN/PNS clinical criteria, 245 patients achieved a clinical diagnosis of typical CIDP or CIDP variant (66%). We identified 106 patients with typical CIDP (29%), 62 distal CIDP (17%), 28 multifocal or focal CIDP (7%), four sensory CIDP (1%), 27 sensory-predominant CIDP (7%), 10 motor CIDP (3%), and eight motor-predominant CIDP (2%). Patients with multifocal, distal, and sensory CIDP had milder impairment and symptoms. Patients with multifocal CIDP had less frequently reduced conduction velocity and prolonged F-wave latency and had lower levels of cerebrospinal fluid protein. Patients with distal CIDP more frequently had reduced distal compound muscle action potentials. Patients with motor CIDP did not improve after steroid therapy, whereas those with motor-predominant CIDP did. None of the patients with sensory CIDP responded to steroids, whereas most of those with sensory-predominant CIDP did. CONCLUSIONS: The 2021 EAN/PNS criteria for CIDP allow a better characterization of CIDP variants, permitting their distinction from typical CIDP and more appropriate treatment for patients.

Rate and characteristics of inflammatory neuropathies associated with brentuximab vedotin therapy.

BACKGROUND AND PURPOSE: Peripheral neuropathy is a frequent complication of brentuximab vedotin (BV), used in CD30+ lymphoma treatment. Classic BV-induced neuropathy (BV-CN) is a mild distal sensory axonal polyneuropathy. Severe BV-induced inflammatory neuropathies (BV-IN) have been described. BV-IN contribute to lymphoma-associated morbidity but might be immunotherapy-responsive. Our primary objective was to evaluate the rate of BV-IN. Our secondary objectives were to determine risk factors and warning signs. METHODS: We conducted a retrospective cohort study on all patients treated with BV at our center between April 2014 and September 2021. Clinical, biological, and electrophysiological data were collected. BV-induced neuropathy was defined as the occurrence of neuropathy up to 3 months after BV discontinuation. BV-IN was defined with criteria adapted from European Academy of Neurology/Peripheral Nerve Society 2021 electrodiagnostic criteria for chronic inflammatory demyelinating polyradiculoneuropathy. Other neuropathies were classified as BV-CN. RESULTS: Among 83 patients, 41 (49%) developed neuropathy: 35 BV-CN and 6 BV-IN. Thus, the rate of BV-IN was 7.2%. Compared to patients with BV-CN, no predisposing factor was identified. However, patients with BV-IN more frequently presented muscle weakness (67% vs. 5.7%, p < 0.05), gait disorders (83% vs. 20%, p < 0.05), or acute or subacute onset (67% vs. 14%, p < 0.05). BV-IN was frequently more severe (Common Terminology Criteria for Adverse Events grade ≥3; 50% vs. 0%, p < 0.05). Four patients were treated with immunotherapy. CONCLUSIONS: Brentuximab vedotin-induced neuropathy is an overlooked complication. Based on four easily identifiable "red flags", we provide an algorithm to help non-neurologist physicians that care for BV-treated patients to detect BV-IN. The aim of the algorithm is to decrease the diagnostic and management delay of this disabling neuropathy.

Cytokines and chemokines in patients with chronic inflammatory demyelinating polyradiculoneuropathy and multifocal motor neuropathy: A systematic review.

Advances in the understanding of cytokines have revolutionized mechanistic treatments for chronic inflammatory and autoimmune diseases, as exemplified by rheumatoid arthritis. We conducted a systematic literature review on the role of cytokines and chemokines in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and multifocal motor neuropathy (MMN). Ovid Medline, EMBASE and Web of Science were searched until August 31, 2022 for human studies investigating cytokines levels in CIDP or MMN. Fifty-five articles on 1061 CIDP patients and 86 MMN patients were included, with a median of 18 patients per study (range 3-71). Studies differed in the inclusion criteria, type of assay, manufacturer, control subjects, and tested biological material. Only a minority of studies reported data on disease activity. Interleukin (IL)-6, IL-17, CXCL10, and tumor necrosis factor alpha (TNF-α), were elevated in CIDP compared to controls in most of the studies. IL-6 and TNF-α levels are also correlated with disability. In MMN patients, IL-1Ra was elevated in the majority of the reports. While acknowledging the challenges in comparing studies and the various limitations of the studies, including small patient numbers, particularly in MMN, our review suggests that IL-6, IL-17, CXCL10, and TNF-α might play a role in CIDP pathogenesis. Larger studies are needed in MMN.

Synergistic effects of immune checkpoints and checkpoint inhibitors in inflammatory neuropathies: Implications and mechanisms.

Immune checkpoint molecules play pivotal roles in the regulation of immune homeostasis. Disruption of the immune checkpoints causes autoimmune/inflammatory as well as malignant disorders. Over the past few years, the immune checkpoint molecules with inhibitory function emerged as potential therapeutic targets in oncological conditions. The inhibition of the function of these molecules by using immune checkpoint inhibitors (ICIs) has brought paradigmatic changes in cancer therapy due to their remarkable clinical benefits, not only in improving the quality of life but also in prolonging the survival time of cancer patients. Unfortunately, the ICIs soon turned out to be a "double-edged sword" as the use of ICIs caused multiple immune-related adverse effects (irAEs). The development of inflammatory neuropathies such as Guillain-Barré syndrome (GBS) and Chronic Inflammatory Demyelinating Polyradiculoneuropathy (CIDP) as the secondary effects of immunotherapy appeared very challenging as these conditions result in significant and often permanent disability. The underlying mechanism(s) through which ICIs trigger inflammatory neuropathies are currently not known. Compelling evidence suggests autoimmune reaction and/or inflammation as the independent risk mechanism of inflammatory neuropathies. There is a lack of understanding as to whether prior exposure to the risk factors of inflammatory neuropathies, the presence of germline genetic variants in immune function-related genes, genetic variations within immune checkpoint molecules, the existence of autoantibodies, and activated/memory T cells act as determining factors for ICI-induced inflammatory neuropathies. Herein, we highlight the available pieces of evidence, discuss the mechanistic basis, and propose a few testable hypotheses on inflammatory neuropathies as irAEs of immunotherapy.

Effects of oral steroid sparing immunosuppressive drugs in long term maintenance treatment of chronic inflammatory demyelinating polyradiculoneuropathy.

Background and objectives: Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an acquired treatable autoimmune disorder. Due to limited availability and affordability of IV immunoglobulins and therapeutic plasma exchange in Pakistan, oral immunosuppressive drugs (ISDs) are used despite limited role in literature. The study aimed to determine the response to ISDs in CIDP patients by assessing the frequency of remission, reduction of disability using a neuropathy related disability score called Inflammatory Neuropathy Cause and Treatment score (or INCAT score), as well as reduction in steroid maintenance dose. Methods: The retrospective observational study of six months duration (May to October, 2020) was carried out in Aga Khan University Hospital, Karachi, Pakistan. Medical record of all the patients with idiopathic CIDP taking oral ISDs in last five years was selected which included bio-data, clinical signs and symptoms, medication details, and INCAT scores. Descriptive statistics were described i.e. frequency, percentages, mean/standard deviation using Microsoft Excel v.2021. Results: Out of thirteen patients, Azathioprine was used in nine, Mycophenolate mofetil in two and Cyclosporine in two, with remission (INCAT score improvement ≥ 1) achieved in eight, one and zero patients respectively. Duration of ISDs ranged from three to twenty-four months (average 15.8 months). Patients with monoclonal paraproteinemia and prior exposure to ISDs had a poor response to the introduction of subsequent ISDs. Conclusion: The study describes preliminary experience of the potential role of relatively cheaper and more convenient oral ISDs (especially Azathioprine) as an alternative or sparing agent to first line agents for CIDP and sets the stage for larger scale studies and randomized controlled trials.

Chronic inflammatory demyelinating polyradiculoneuropathy in a patient with systemic lupus erythematosus without systemic activity.

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an uncommon subtype of peripheral neuropathy, especially in systemic lupus erythematosus (SLE). We report a case of SLE presenting with CIDP successfully treated. The patient presented with bilateral, progressive, ascending, sensory, and motor neuropathy. Electrodiagnostic tests reported active motor and sensitive demyelinating polyneuropathy, and the diagnosis of CIDP was confirmed according to the European Federation of Neurological Societies/Peripheral Nerve Society criteria. Initial management with intravenous immunoglobulin and high-dose steroids was administered, then 6-month intravenous cyclophosphamide was initiated with improvement according to clinical scales. In conclusion, CIDP in SLE is rare, reported in just 0.2%. Immunosuppressive therapy should be considered whether initial improvement is not evidenced, as seen in our case requiring cyclophosphamide; interestingly, systemic activity was in remission as the peripheral nervous system is not part of neurological compromise, and we suggest evaluating this unusual presentation into rheumatological practice.

A diagnostic score for anti-myelin-associated-glycoprotein neuropathy or chronic inflammatory demyelinating polyradiculoneuropathy in patients with anti-myelin-associated-glycoprotein antibody.

BACKGROUND AND PURPOSE: A diagnostic score was developed to discriminate anti-myelin-associated-glycoprotein (MAG) neuropathy from chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and applied it to patients with atypical anti-MAG neuropathy. METHODS: The clinical and electrophysiological features of patients with a diagnosis of typical anti-MAG neuropathy were compared to those of patients with a diagnosis of CIDP. The association of each feature with the diagnosis was assessed in the two groups. Features showing a significant association with the diagnosis were included in a multivariable logistic regression model and adjusted odds ratios were estimated for each feature. A score ranging from 1 to 3 was applied to each feature based on the magnitude of the estimated odds ratios. The score was then applied to patients with a clinical diagnosis of CIDP who also had high anti-MAG antibody titers (CIDP-MAG). RESULTS: Thirty-one anti-MAG neuropathy patients, 45 typical CIDP patients and 16 CIDP-MAG patients were included. Scores in anti-MAG antibody patients ranged from 1 to 5 and in CIDP patients from -7 to -1. Using the score, 4/16 CIDP-MAG patients were diagnosed to have anti-MAG neuropathy and 12/16 patients to have CIDP. Response to intravenous immunoglobulin in the CIDP-MAG patients classified as CIDP was similar to that of definite CIDP patients and higher than that of anti-MAG neuropathy patients. CONCLUSIONS: Our score allowed an accurate discrimination to be made, amongst patients with anti-MAG antibodies, of those affected by CIDP and the patients with anti-MAG neuropathy. This score may help proper treatment to be chosen for patients with anti-MAG antibodies with a CIDP-like presentation.

Chronic inflammatory demyelinating polyradiculoneuropathy: Diagnostic problems in clinical practice in Serbia.

Making diagnosis of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is challenging since it can mimic a multitude of disorders, and is misdiagnosed in at least 50% of cases. We sought to determine the frequency of CIDP misdiagnosis in clinical practice in Serbia, to uncover CIDP mimics, and to identify factors that may aid in CIDP diagnosis. Our longitudinal retrospective cohort study included 86 eligible adult patients referred to the Neurology Clinic, University Clinical Centre of Serbia, with a diagnosis of CIDP. We also included 15 patients referred to us with different diagnoses that ended up having CIDP as their final diagnosis. Exactly half of patients referred as CIDP failed to meet the established diagnostic criteria (non-CIDP) and were given an alternative diagnosis at the first hospitalization. At the 1-year follow-up, the diagnosis was further revised in four subjects. Confirmed CIDP patients usually had their initial diagnosis based on the nerve conduction studies (NCS), a typical presentation with symmetrical involvement of all four limbs, as well as higher frequencies of elevated protein levels and albuminocytologic dissociation in the cerebrospinal fluid (CSF). CIDP patients also responded better to immune therapy. We found that 52% of the patients initially referred to our Clinic as CIDP were given other diagnoses after a 1-year follow-up. Out of all CIDP cases, 27% had been unrecognized prior to referral to our Center. Utilization of clear and objective indicators - conclusive NCS, improvement on therapy, and elevated CSF proteins may provide greater certainty in diagnosing CIDP.

Hyaluronidase-facilitated subcutaneous immunoglobulin 10% as maintenance therapy for chronic inflammatory demyelinating polyradiculoneuropathy: The ADVANCE-CIDP 1 randomized controlled trial.

BACKGROUND AND AIMS: ADVANCE-CIDP 1 evaluated facilitated subcutaneous immunoglobulin (fSCIG; human immunoglobulin G 10% with recombinant human hyaluronidase) efficacy and safety in preventing chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) relapse. METHODS: ADVANCE-CIDP 1 was a phase 3, double-blind, placebo-controlled trial conducted at 54 sites in 21 countries. Eligible adults had definite or probable CIDP and adjusted Inflammatory Neuropathy Cause and Treatment (INCAT) disability scores of 0-7 (inclusive), and received stable intravenous immunoglobulin (IVIG) for ≥12 weeks before screening. After stopping IVIG, patients were randomized 1:1 to fSCIG 10% or placebo for 6 months or until relapse/discontinuation. fSCIG 10% was administered at the same dose (or matching placebo volume) and interval as pre-randomization IVIG. The primary outcome was patient proportion experiencing CIDP relapse (≥1-point increase in adjusted INCAT score from pre-subcutaneous treatment baseline) in the modified intention-to-treat population. Secondary outcomes included time to relapse and safety endpoints. RESULTS: Overall, 132 patients (mean age 54.4 years, 56.1% male) received fSCIG 10% (n = 62) or placebo (n = 70). CIDP relapse was reduced with fSCIG 10% versus placebo (n = 6 [9.7%; 95% confidence interval 4.5%, 19.6%] vs n = 22 [31.4%; 21.8%, 43.0%], respectively; absolute difference: -21.8% [-34.5%, -7.9%], p = .0045). Relapse probability was higher with placebo versus fSCIG 10% over time (p = .002). Adverse events (AEs) were more frequent with fSCIG 10% (79.0% of patients) than placebo (57.1%), but severe (1.6% vs 8.6%) and serious AEs (3.2% vs 7.1%) were less common. INTERPRETATION: fSCIG 10% more effectively prevented CIDP relapse than placebo, supporting its potential use as maintenance CIDP treatment.

Autonomic nervous system involvement in chronic inflammatory demyelinating polyradiculoneuropathy: a literature review.

BACKGROUND AND AIMS: Although dysautonomia is a well-recognized complication of acute demyelinating polyradiculoneuropathy, it is rarely reported and evaluated in chronic demyelinating neuropathies. The purpose of this review is to search and synthesize the current literature on the prevalence and type of autonomic dysfunction (AD) in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). METHODS: PubMed and Web of Science were searched for studies reporting AD in CIDP. RESULTS: Twelve studies, including 346 patients with CIDP, were found eligible for the review. Seven studies used autonomic tests only as an additional component of the comprehensive clinical evaluation, and found that dysautonomia in CIDP may indicate the presence of a comorbid disease (e.g., diabetes) and facilitate the differentiation of CIDP from other neuropathies (e.g., amyloid neuropathy). Five studies performed quantitative assessment of autonomic function in CIDP as a primary goal. Two studies have used the Composite Autonomic Severity Score (CASS) to assess severity and distribution of dysautonomia. The reported prevalence of dysautonomia in CIDP during quantitative assessment of autonomic function ranged from 25 to 89%, depending on the battery of tests used, with CASS not exceeding 4 points. The abnormalities in autonomic tests indicated both sympathetic and parasympathetic dysfunction and did not correlate with the duration, severity and variant of CIDP. CONCLUSIONS: Clinical or subclinical involvement of the ANS has been shown to be common and relatively mild in CIDP. The impact of autonomic impairment on disability and of its possible response to therapy in CIDP needs to be further investigated.

Two Case Reports of Chronic Inflammatory Demyelinating Polyneuropathy After COVID-19 Vaccination.

The occurrence of chronic inflammatory demyelinating polyneuropathy (CIDP) related to coronavirus disease 2019 (COVID-19) has rarely been reported. We describe two patients who were diagnosed with CIDP after COVID-19 vaccination. A 72-year-old man presented with a progressive tingling sensation and weakness below both knees for two weeks. He had been vaccinated against COVID-19 (mRNA-1273 vaccine) a month before the appearance of symptoms. Demyelinating polyneuropathy was observed in the nerve conduction studies (NCS). Intravenous immunoglobulin (IVIg) was administered under the diagnosis of Guillain-Barré syndrome (GBS), and his symptoms were improved. However, his symptoms relapsed at 10 weeks from the onset. Oral prednisolone, azathioprine, and IVIg were administered as treatment. The second case was a 50-year-old man who complained of a bilateral leg tingling sensation and gait disturbance lasting four weeks. He had received the Ad26.COV2.S vaccine against COVID-19 five weeks prior. Demyelinating polyneuropathy was observed in the NCS. He was treated with oral prednisolone, azathioprine, and IVIg for CIDP because his symptoms had lasted for more than 12 weeks from the onset. A causal relationship has not been established between COVID-19 vaccination and CIDP; however, CIDP may follow COVID-19 vaccination. As CIDP treatment is different from that for GBS, clinicians should closely monitor patients diagnosed with GBS associated with COVID-19 whether they deteriorate after initial treatment.

Acute-onset polyradiculoneuropathy after SARS-CoV2 vaccine in the West and North Midlands, United Kingdom.

INTRODUCTION/AIMS: We aimed to determine whether specific severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) vaccines may be associated with acute-onset polyradiculoneuropathy and if they may result in particular clinical presentations. METHODS: We retrospectively reviewed records of all persons presenting with acute-onset polyradiculoneuropathy from January 1, 2021, to June 30, 2021, admitted to two Neuroscience centers, of the West and North Midlands, United Kingdom. We compared subjects with previous SARS-CoV2 vaccine exposure with a local cohort of persons with acute-onset polyradiculoneuropathy admitted between 2005 and 2019 and compared admission numbers for the studied time frame with that of the previous 3 years. RESULTS: Of 24 persons with acute-onset polyradiculoneuropathy, 16 (66.7%) presented within 4 weeks after first SARS-CoV2 vaccine. Fourteen had received the AstraZeneca vaccine and one each, the Pfizer and Moderna vaccines. The final diagnosis was Guillain-Barré syndrome (GBS) in 12 and acute-onset chronic inflammatory demyelinating polyneuropathy in 4. Among AstraZeneca vaccine recipients, facial weakness in nine persons (64.3%), bulbar weakness in seven (50%), and the bifacial weakness and distal paresthesias GBS variant in three (21.4%), were more common than in historical controls (P = .01; P = .004, and P = .002, respectively). A 2.6-fold (95% confidence interval: 1.98-3.51) increase in admissions for acute-onset polyradiculoneuropathy was noted during the studied time frame, compared to the same period in the previous 3 years. DISCUSSION: Despite a low risk, smaller than that of SARS-CoV2 infection and its complications, exposure to the first dose of AstraZeneca SARS-CoV2 vaccine may be a risk factor for acute-onset polyradiculoneuropathy, characterized by more common cranial nerve involvement.

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.

Axonal damage determines clinical disability in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP): A prospective cohort study of different CIDP subtypes and disease stages.

BACKGROUND AND PURPOSE: Monitoring of patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is challenging in daily medical practice because the interrelationship between clinical disability, CIDP subtype, and neuronal degeneration is still elusive. The aim of this prospective cohort study was to investigate the role of different electrophysiological variables in CIDP monitoring. METHODS: Comprehensive bilateral nerve conduction studies (NCS) and structured clinical examinations were performed in 95 patients with typical CIDP and CIDP variants (age at inclusion 58.6 ± 11.6 years; median [range] inflammatory neuropathy cause and treatment overall disability score (INCAT-ODSS) 3 [0-9]), at time of first diagnosis in 25 of these patients (based on data from the prospective Immune-mediated Neuropathies Biobank registry). After 12 months, 33 patients underwent follow-up examination. Typical CIDP patients and patients with CIDP variants were characterized electrophysiologically and each individual NCS variable and the overall sum score for axonal damage and demyelination were then correlated to clinical disability scores (INCAT-ODSS, modified Medical Research Council (MRS) sum score, and INCAT sensory score). RESULTS: As opposed to demyelination markers, the NCS axonal damage variable correlated strongly with disability at both first diagnosis and advanced disease stages in cross-sectional and longitudinal analyses. Distal compound muscle action potential amplitudes of the upper limbs were found to have the strongest correlation with overall clinical function. Typical and atypical CIDP variants had distinct electrophysiological characteristics but, in typical CIDP, axonal degeneration markers were more strongly associated with clinical disability. CONCLUSIONS: Total disability is largely determined by the degree of axonal damage, especially in typical CIDP. Although most patients have symptoms predominantly in the legs, NCS of the upper limbs are essential for the monitoring of patients with CIDP and CIDP variants.

Epidemiology of chronic inflammatory demyelinating polyradiculoneuropathy in The Netherlands.

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a rare but disabling disorder that often requires long-term immunomodulatory treatment. Background incidence rates and prevalence and risk factors for developing CIDP are still poorly defined. In the current study, we used a longitudinal population-based cohort study in The Netherlands to assess these rates and demographic factors and comorbidity associated with CIDP. We determined the incidence rate and prevalence of CIDP between 2008 and 2017 and the occurrence of potential risk factors in a retrospective Dutch cohort study using the Integrated Primary Care Information (IPCI) database. Cases were defined as CIDP if the diagnosis of CIDP was described in the electronic medical file. In a source population of 928 030 persons with a contributing follow-up of 3 525 686 person-years, we identified 65 patients diagnosed with CIDP. The overall incidence rate was 0.68 per 100 000 person-years (95% CI 0.45-0.99). The overall prevalence was 7.00 per 100 000 individuals (95% CI 5.41-8.93). The overall incidence rate was higher in men compared to woman (IRR 3.00, 95% CI 1.27-7.11), and higher in elderly of 50 years or older compared with people <50 years of age (IRR 17 95% CI 4-73). Twenty percent of CIDP cases had DM and 9% a co-existing other auto-immune disease. These background rates are important to monitor changes in the frequency of CIDP following infectious disease outbreaks, identify potential risk factors, and to estimate the social and economic burden of CIDP.

Chronic inflammatory demyelinating polyradiculoneuropathy concomitant with nephropathy.

BACKGROUND: Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is one of the most common autoimmune peripheral neuropathies in adults. Membranous nephropathy (MN), focal segmental glomerulosclerosis (FSGS), and other nephropathy have been reported in CIDP patients and are possibly correlated to CIDP pathogenesis. This study reviewed the previously described cases of patients with CIDP and nephropathy in order to provide comprehensive evidence on the diagnosis and treatment regarding CIDP patients in the context of renal diseases. METHOD: We reviewed our database to identify patients with CIDP and nephropathy. Online database including PubMed, EMBASE, and OVID were searched for relevant cases. RESULTS: We identified a total of 18 cases with CIDP and nephropathy, including 2 cases from our database and 16 ones from online searching. A predominance of male was observed [14 (77.8%)] with the mean age of 53.3 (standard deviation, SD: 16.6) years old. Almost all patients complained paresthesia in distal limbs (94.4%), except one only presented weakness of four extremities. Corticosteroids were prescribed for 14 (77.8%) patients, and 10 showed responsiveness. Three patients experienced relapses during the gradual tapering of steroids. CONCLUSION: The same immune-mediated pathogenesis may be involved in CIDP and concomitant nephropathy. Male and sensory-predominant CIDP are red flags for complications of renal diseases in CIDP patients. Corticosteroids remain the first-line treatment for CIDP when complicated with renal diseases. Slower tapering or long-term maintenance of steroids may be beneficial for the prognosis of patients with CIDP and nephropathy.

Nerve ultrasound may help predicting response to immune treatment in chronic inflammatory demyelinating polyradiculoneuropathy.

BACKGROUNDS: Nerve ultrasound has been proven to be an accurate tool in diagnosing chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). However, its value in guiding treatment has not been well evaluated. The aim of this study was to explore whether nerve ultrasound and its changing trend could predict the response to immune treatment in CIDP. METHODS: Eighty-nine therapy-naive CIDP patients were recruited prospectively and treated with steroids and/or intravenous immunoglobulin (IVIG). Ultrasonographic and electrophysiological studies were performed on the median and ulnar nerves before treatment in all patients and followed up in 45 patients. The cross-sectional area (CSA) was measured at ten sites on both the median and ulnar nerves. RESULTS: The response rate to steroids (95%) was significantly higher than that to IVIG (70%) (P = 0.001) in patients with normal or moderately enlarged CSA, while there was no significant difference in the response rate between steroid therapy (84%) and IVIG (75%) (P = 0.653) in patients with markedly enlarged CSA. CSAs decreased in 15 patients during follow-up, most of whom had good IVIG and steroid responses (83%) and no need for immune suppressant treatment (82%). CONCLUSIONS: Nerve ultrasonography could help guide treatment strategies in patients with CIDP. Patients with normal or moderately enlarged CSA may respond better to steroids than to IVIG. The decrease in CSA after treatment may also indicate better prognosis.