Chronic inflammatory demyelinating polyneuropathy

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.

Whole-body magnetic resonance neurography in patients with chronic inflammatory demyelinating polyneuropathy

INTRODUCTION/AIMS

Whole-body magnetic resonance neurography (MRN) is an imaging modality that shows peripheral nerve signal change in patients with chronic inflammatory demyelinating polyneuropathy (CIDP). We aimed to explore the diagnostic potential of whole-body MRN and its potential as a monitoring tool after immunotherapy in treatment-naïve CIDP patients.

METHODS

Whole-body MRN using coronal 3-dimensional short tau inversion recovery (STIR) sampling perfection with application-optimized contrasts by using different flip angle evolution (SPACE) techniques was performed in patients being investigated for CIDP and in healthy controls. Baseline clinical neuropathy scales and electrophysiologic parameters were collected, and MRN findings were compared before and after CIDP treatment.

RESULTS

We found highly concordant symmetrical thickening and increased T2 signal intensities in the brachial/lumbosacral plexus, femoral, or sciatic nerves in five of the eight patients with a final diagnosis of CIDP and none of the healthy controls. There were no treatment-related imaging changes in five patients with CIDP who completed a follow-up study. Diffuse, symmetrical thickening, and increased T2 signal in root, plexus, and peripheral nerves were found in two patients ultimately excluded due to a diagnosis of polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, skin changes (POEMS) syndrome in addition to signal changes in the muscles, bony lesions, organomegaly, and lymphadenopathy.

DISCUSSION

Whole-body MRN imaging shows promise in detecting abnormalities in proximal nerve segments in patients with CIDP. Future studies evaluating the role of MRN in assessing treatment response should consider follow-up scans after treatment durations of more than 4 months.

Ultramicronized Palmitoylethanolamide in the Management of Neuropathic Pain Related to Chronic Inflammatory Demyelinating Polyneuropathy: A Proof-of-Concept Study

Background/Objectives: Chronic inflammatory demyelinating polyneuropathy (CIDP) is a rare autoimmune disease. Neuropathic pain (NP), related to peripheral inflammation, is among its earliest manifestations. This preliminary open-label investigation aimed to evaluate the efficacy of ultramicronized Palmitoylethanolamide (umPEA) in the management of NP. Methods: A total of 14 patients with CIDP, already undergoing immunoglobulin (Ig) therapy, were divided into two groups: Group A received umPEA 600 mg twice daily in addition to Ig for 60 days, followed by Ig alone until the end of the observation (180 days); Group B received Ig alone for 120 days and subsequently umPEA + Ig in the last 60 days of the study. Painful symptom intensity and quality of life were assessed by the Numeric Rating Scale, Neuropathic Pain Symptoms Inventory, and Five Dimensions Health Questionnaire. The safety umPEA profile was evaluated. Results: UmPEA in addition to immunoglobulins allowed for a significant improvement over time in all NP symptoms intensity (p = 0.0007) and in patients' quality of life (p = 0.0036). Conclusions: This study suggests umPEA as a safe and effective treatment in addition to immunoglobulins to improve NP, ameliorating the patient's health status. These results highlight the importance of neuroinflammation modulation in the management of CIDP's painful symptoms, drawing attention to umPEA's potential use also in neuropathies of different etiologies.

Recurrent acute-onset of chronic inflammatory demyelinating polyneuropathy after COVID-19 vaccination

This is the case of 54-year-old male with a past medical history of Chronic Inflammatory Demyelinating Polyneuropathy (CIPD) who was found to have an acute exacerbation of CIPD shortly after receiving his 1st COVID 19 booster (3rd dose of vaccination series) and was successfully treated with intravenous immunoglobulin (IVIG) and then was found to have another acute exacerbation of CIDP 6 months later after receiving his 2nd COVID 19 booster (4th dose of vaccination series) that required intubation and long term tracheostomy. CIPD is an acquired immune-mediated polyneuropathy that mainly affects the peripheral nerve roots nerves. It typically presents with relapsing/remitting, or progressive symmetrical muscle weakness and sensory involvement and can cause decreased respiratory effort. COVID-19 is mainly a respiratory disease, but it has been associated with a wide variety of neurological conditions. Although there have been several findings of acute inflammatory demyelinating polyneuropathy in association with COVID-19, CIDP exacerbation as a result of COVID-19 has rarely been seen in the literature. Furthermore, CIDP exacerbation as a result of COVID-19 vaccination is even less frequently seen.

Immune-Mediated Neuropathies: Pathophysiology and Management

Dysfunction of the immune system can result in damage of the peripheral nervous system. The immunological mechanisms, which include macrophage infiltration, inflammation and proliferation of Schwann cells, result in variable degrees of demyelination and axonal degeneration. Aetiology is diverse and, in some cases, may be precipitated by infection. Various animal models have contributed and helped to elucidate the pathophysiological mechanisms in acute and chronic inflammatory polyradiculoneuropathies (Guillain-Barre Syndrome and chronic inflammatory demyelinating polyradiculoneuropathy, respectively). The presence of specific anti-glycoconjugate antibodies indicates an underlying process of molecular mimicry and sometimes assists in the classification of these disorders, which often merely supports the clinical diagnosis. Now, the electrophysiological presence of conduction blocks is another important factor in characterizing another subgroup of treatable motor neuropathies (multifocal motor neuropathy with conduction block), which is distinct from Lewis-Sumner syndrome (multifocal acquired demyelinating sensory and motor neuropathy) in its response to treatment modalities as well as electrophysiological features. Furthermore, paraneoplastic neuropathies are also immune-mediated and are the result of an immune reaction to tumour cells that express onconeural antigens and mimic molecules expressed on the surface of neurons. The detection of specific paraneoplastic antibodies often assists the clinician in the investigation of an underlying, sometimes specific, malignancy. This review aims to discuss the immunological and pathophysiological mechanisms that are thought to be crucial in the aetiology of dysimmune neuropathies as well as their individual electrophysiological characteristics, their laboratory features and existing treatment options. Here, we aim to present a balance of discussion from these diverse angles that may be helpful in categorizing disease and establishing prognosis.

Vision Loss as a Presenting Feature of Chronic Inflammatory Demyelinating Polyneuropathy: A Case Series

BACKGROUND

Chronic inflammatory demyelinating polyneuropathy (CIDP) is an acquired, immune-mediated, and clinically heterogeneous demyelinating disease affecting the nerve roots and peripheral nerves. We report a series of 4 patients who presented with early and progressive vision loss in the context of new-onset CIDP: 3 due to papilledema and 1 due to optic neuropathy without papilledema.

METHODS

This was a retrospective case series of 4 patients with vision loss as a presenting feature of CIDP evaluated at the Hospital of the University of Pennsylvania from January 2016 to August 2021. Demographic, clinical, diagnostic, and treatment data were collected via retrospective medical record review.

RESULTS

Case 1 was a 51-year-old man with 2 months of progressive bilateral papilledema associated with reduced visual acuity (count fingers at 1 foot in each eye) and severely constricted visual fields. Case 2 was a 36-year-old man with 4 months of worsening headaches, reduced visual acuity (count fingers at 1 foot in each eye), severely constricted visual fields, and papilledema. Case 3 was a 39-year-old man with papilledema causing progressive vision loss (20/80 in both eyes), headaches, and relapsing limb sensorimotor deficits. Case 4 was a 19-year-old man with 3 months of progressive bilateral visual decline (20/400 in the right eye, 20/600 in the left eye), central scotoma, and optic disc pallor consistent with optic neuropathy without papilledema. All 4 patients met clinical and electrodiagnostic criteria of CIDP. Cases 3 and 4 each tested positive for serum neurofascin-155 IgG4 antibodies. All patients were managed with immunomodulatory therapy. Cases 1 and 2 also each required surgical intervention with bilateral optic nerve sheath fenestration and cerebrospinal fluid (CSF) shunting procedures.

CONCLUSION

Vision loss from optic neuropathy with or without papilledema has rarely been reported in CIDP, and typically has been described in the context of longstanding disease. Our cases highlight how CIDP can present with early vision loss that may be profound and challenging to manage if diagnosis is delayed. CIDP should be considered in any patient with new progressive vision loss when associated with peripheral sensorimotor symptoms and elevated CSF protein. The small subgroup of CIDP patients with neurofascin-155 antibodies may be at particular risk of optic nerve involvement.

Role of tubulin post-translational modifications in peripheral neuropathy

Peripheral neuropathy is a common disorder that results from nerve damage in the periphery. The degeneration of sensory axon terminals leads to changes or loss of sensory functions, often manifesting as debilitating pain, weakness, numbness, tingling, and disability. The pathogenesis of most peripheral neuropathies remains to be fully elucidated. Cumulative evidence from both early and recent studies indicates that tubulin damage may provide a common underlying mechanism of axonal injury in various peripheral neuropathies. In particular, tubulin post-translational modifications have been recently implicated in both toxic and inherited forms of peripheral neuropathy through regulation of axonal transport and mitochondria dynamics. This knowledge forms a new area of investigation with the potential for developing therapeutic strategies to prevent or delay peripheral neuropathy by restoring tubulin homeostasis.

Repurposing MS immunotherapies for CIDP and other autoimmune neuropathies: unfulfilled promise or efficient strategy?

Despite advances in the treatment of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and other common autoimmune neuropathies (AN), still-many patients with these diseases do not respond satisfactorily to the available treatments. Repurposing of disease-modifying therapies (DMTs) from other autoimmune conditions, particularly multiple sclerosis (MS) and neuromyelitis optica spectrum disorders (NMOSD), is a promising strategy that may accelerate the establishment of novel treatment choices for AN. This approach appears attractive due to homologies in the pathogenesis of these diseases and the extensive post-marketing experience that has been gathered from treating MS and NMOSD patients. The idea is also strengthened by a number of studies that explored the efficacy of DMTs in animal models of AN but also in some CIDP patients. We here review the available preclinical and clinical data of approved MS therapeutics in terms of their applicability to AN, especially CIDP. Promising therapeutic approaches appear to be B cell-directed and complement-targeting strategies, such as anti-CD20/anti-CD19 agents, Bruton's tyrosine kinase inhibitors and anti-C5 agents, as they exert their effects in the periphery. This is a major advantage because, in contrast to MS, their action in the periphery is sufficient to exert significant immunomodulation.

Processing speed impairment in chronic inflammatory demyelinating polyneuropathy patients: a cross-sectional study

BACKGROUND

There is a lack of evidence of cognitive involvement in chronic inflammatory demyelinating polyneuropathy (CIDP) and, the reports about the involvement of the brain and central nervous system (CNS) are few and controversial. The Five Digit Test (FDT) evaluates processing speed (PS) and executive functions orally.

OBJECTIVE

To evaluate the performance on the FDT of CIDP patients with and without CNS (brain/cerebellum) alterations observed on brain Magnetic Resonance Imaging (MRI) scans.

METHODS

The Hospital Anxiety and Depression Scale (HADS, to assess neuropsychiatry symptoms), the Rasch-built Overall Disability Scale (R-ODS; to assess disability), and the FDT (to assess cognition) were applied to 14 CIDP patients and 24 age-matched healthy control subjects. The patients were submitted to routine brain MRI and, according to the results, they were divided into two groups: those with abnormalities on the MRI (CIDPabnl) and those with normal parameters on the MRI (CIDPnl). The FDT data of five CIDPnl patients and nine CIDPabnl subjects were analyzed. Comparisons between the groups were performed for each task of the FDT.

RESULTS

We found statistical differences for both groups of CIDP patients in terms of PS, for the patients spent more time performing the PS tasks than the controls. The PS measures were negatively associated with disability scores (reading: r = -0.47; p = 0.003; counting: r = -0.53; p = 0.001).

CONCLUSIONS

Our data suggested the presence of PS impairment in CIDP patients. Disability was associated with slow PS.

Axonal loss at time of diagnosis as biomarker for long-term disability in chronic inflammatory demyelinating polyneuropathy

INTRODUCTION/AIMS

We hypothesized that early, pretreatment axonal loss would predict long-term disability, supported by a pilot study of selected patients with chronic inflammatory demyelinating polyneuropathy (CIDP). To further test this hypothesis, we examined a larger consecutive group of CIDP patients.

METHODS

Needle electromyography and motor and sensory nerve conduction studies were carried out in 30 CIDP patients at pretreatment and follow-up 5 to 28 years later. Changes in amplitudes were expressed as axonal Z scores and changes in conduction as demyelination Z scores and correlated with findings of the Inflammatory Rasch-built Overall Disability Scale (I-RODS), the Neuropathy Impairment Score (NIS), and isokinetic dynamometry (IKS).

RESULTS

At follow-up, the median I-RODS score was 73, the NIS was 23, and the IKS was 56%. The median axonal Z score was unchanged at follow-up. Conversely, the corresponding demyelination Z scores improved. The initial axonal loss was correlated with the clinical outcome and was an independent predictor of outcome by multivariate regression analysis. Axonal loss at follow-up was also correlated with the clinical outcome. Only the follow-up demyelination Z score was correlated with the clinical outcomes. Furthermore, the latency until treatment initiation was predictive of all three clinical outcome scores at follow-up, and of axonal loss and demyelination at follow-up.

DISCUSSION

The present study findings indicate that pretreatment axonal loss at diagnosis in CIDP is predictive of long-term disability, neurological impairment, and strength. A delay in treatment is associated with more pronounced axonal loss and a worse clinical outcome.

Intravenous immunoglobulin in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP): mechanisms of action and clinical and genetic considerations

INTRODUCTION

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an autoimmune peripheral nerve disorder that is characterized by subacute onset, progressive or relapsing weakness, and sensory deficits. Proven treatments include intravenous immunoglobulin (IVIg), corticosteroids, and plasma exchange. This review focuses on the mechanisms of action, pharmacodynamics, genetic variations, and disease characteristics that can affect the efficacy of IVIg.

AREAS COVERED

The proposed mechanisms of action of IVIg that can mediate its therapeutic effects are reviewed. These include anti-idiotypic interactions, inhibition of neonatal Fc receptors (FcRn), anti-complement activity, upregulation of inhibitory FcγRIIB receptors, and downregulation of macrophage activation or co-stimulatory and adhesion molecules. Clinical and genetic factors that can affect the therapeutic response include misdiagnosis, degree of axonal damage, pharmacokinetic variability, and genetic variations.

EXPERT OPINION

The mechanisms of action of IVIg in CIDP and their relative contribution to its efficacy are subject of ongoing investigation. Studies in other autoimmune neurological conditions, in addition, highlight the role of key immunopathological pathways and factors that are likely to be affected. Further investigation into the pathogenesis of CIDP and the mechanisms of action of IVIg may lead to the development of improved diagnostics, better utilization of IVIg, and more targeted and effective therapies.

Autoimmune Disease Classification Based on PubMed Text Mining

Autoimmune diseases (AIDs) are often co-associated, and about 25% of patients with one AID tend to develop other comorbid AIDs. Here, we employ the power of datamining to predict the comorbidity of AIDs based on their normalized co-citation in PubMed. First, we validate our technique in a test dataset using earlier-reported comorbidities of seven knowns AIDs. Notably, the prediction correlates well with comorbidity (R = 0.91) and validates our methodology. Then, we predict the association of 100 AIDs and classify them using principal component analysis. Our results are helpful in classifying AIDs into one of the following systems: (1) gastrointestinal, (2) neuronal, (3) eye, (4) cutaneous, (5) musculoskeletal, (6) kidneys and lungs, (7) cardiovascular, (8) hematopoietic, (9) endocrine, and (10) multiple. Our classification agrees with experimentally based taxonomy and ranks AID according to affected systems and gender. Some AIDs are unclassified and do not associate well with other AIDs. Interestingly, Alzheimer’s disease correlates well with other AIDs such as multiple sclerosis. Finally, our results generate a network classification of autoimmune diseases based on PubMed text mining and help map this medical universe. Our results are expected to assist healthcare workers in diagnosing comorbidity in patients with an autoimmune disease, and to help researchers in identifying common genetic, environmental, and autoimmune mechanisms.

Clinical Course and Diagnostic Findings of Biopsy Controlled Presumed Immune-Mediated Polyneuropathy in 70 European Cats

There is a paucity of information on the clinical course and outcome of young cats with polyneuropathy. The aim of the study was to describe the clinical features, diagnostic investigations, and outcome of a large cohort of cats with inflammatory polyneuropathy from several European countries. Seventy cats with inflammatory infiltrates in intramuscular nerves and/or peripheral nerve biopsies were retrospectively included. Information from medical records and follow up were acquired via questionnaires filled by veterinary neurologists who had submitted muscle and nerve biopsies (2011–2019). Median age at onset was 10 months (range: 4–120 months). The most common breed was British short hair (25.7%), followed by Domestic short hair (24.3%), Bengal cat (11.4%), Maine Coon (8.6%) and Persian cat (5.7%), and 14 other breeds. Male cats were predominantly affected (64.3%). Clinical signs were weakness (98.6%) and tetraparesis (75.7%) in association with decreased withdrawal reflexes (83.6%) and, less commonly, cranial nerve signs (17.1%), spinal pain/hyperesthesia (12.9%), and micturition/defecation problems (14.3%). Onset was sudden (30.1%) or insidious (69.1%), and an initial progressive phase was reported in 74.3%. Characteristic findings on electrodiagnostic examination were presence of generalized spontaneous electric muscle activity (89.6%), decreased motor nerve conduction velocity (52.3%), abnormal F-wave studies (72.4%), pattern of temporal dispersion (26.1%) and unremarkable sensory tests. The clinical course was mainly described as remittent (49.2%) or remittent-relapsing (34.9%), while stagnation, progressive course or waxing and waning were less frequently reported. Relapses were common and occurred in 35.7% of the cats' population. An overall favorable outcome was reported in 79.4% of patients. In conclusion, young age at the time of diagnosis and sudden onset of clinical signs were significantly associated with recovery (p < 0.05). Clinical and electrodiagnostic features and the remittent-relapsing clinical course resembles juvenile chronic inflammatory demyelinating polyneuropathy (CIDP), as seen in human (children/adolescents), in many aspects.

Tacrolimus treatment for relapsing-remitting chronic inflammatory demyelinating polyradiculoneuropathy: Two case reports

BACKGROUND

This study describes the efficacy of a tacrolimus treatment regimen used to treat two patients with relapsing-remitting chronic inflammatory demyelinating polyradiculoneuropathy (CIDP).

CASE SUMMARY

Two patients (17-year-old female and 27-year-old male) were enrolled in the current study and were followed up for 12 mo. The first patient was administered tacrolimus (2 mg/d) for 12 mo and prednisolone (40 mg/d) for six months. The second patient was administered tacrolimus (3 mg/d) for six months. Both patients were followed up for 12 mo and the degree of recurrent weakness or normalized motor function was monitored. In addition, nerve conduction studies and tacrolimus levels were recorded. Following tacrolimus treatment, both patients showed marked improvement in clinical outcomes. In the first patient, prednisolone treatment was successfully withdrawn after six months. Sensory as well as motor nerve conduction velocities showed evident recovery following treatment. However, conduction velocities did not completely return to normal, suggesting that electrophysiological recovery can be slower than clinical recovery.

CONCLUSION

Neither patient exhibited any adverse effects due to the tacrolimus therapy. Therefore, tacrolimus can be effective for the treatment of patients with steroid-resistant CIDP.

Pathogenic TNF-α drives peripheral nerve inflammation in an Aire-deficient model of autoimmunity

Immune cells infiltrate the peripheral nervous system (PNS) after injury and with autoimmunity, but their net effect is divergent. After injury, immune cells are reparative, while in inflammatory neuropathies (e.g., Guillain Barré Syndrome and chronic inflammatory demyelinating polyneuropathy), immune cells are proinflammatory and promote autoimmune demyelination. An understanding of immune cell phenotypes that distinguish these conditions may, therefore, reveal new therapeutic targets for switching immune cells from an inflammatory role to a reparative state. In an autoimmune regulator (Aire)-deficient mouse model of inflammatory neuropathy, we used single-cell RNA sequencing of sciatic nerves to discover a transcriptionally heterogeneous cellular landscape, including multiple myeloid, innate lymphoid, and lymphoid cell types. Analysis of cell-cell ligand-receptor interactions uncovered a macrophage-mediated tumor necrosis factor-α (TNF-α) signaling axis that is induced by interferon-γ and required for initiation of autoimmune demyelination. Developmental trajectory visualization suggested that TNF-α signaling is associated with metabolic reprogramming of macrophages and polarization of macrophages from a reparative state in injury to a pathogenic, inflammatory state in autoimmunity. Autocrine TNF-α signaling induced macrophage expression of multiple genes (Clec4e, Marcksl1, Cxcl1, and Cxcl10) important in immune cell activation and recruitment. Genetic and antibody-based blockade of TNF-α/TNF-α signaling ameliorated clinical neuropathy, peripheral nerve infiltration, and demyelination, which provides preclinical evidence that the TNF-α axis may be effectively targeted to resolve inflammatory neuropathies.

CIDP: Current Treatments and Identification of Targets for Future Specific Therapeutic Intervention

Chronic inflammatory demyelinating polyneuropathy (CIDP) is an acquired immune-mediated inflammatory disorder of the peripheral nervous system. This clinically heterogeneous neurological disorder is closely related to Guillain–Barré syndrome and is considered the chronic counterpart of that acute disease. Currently available treatments are mostly empirical; they include corticosteroids, intravenous immunoglobulins, plasma exchange and chronic immunosuppressive agents, either alone or in combination. Recent advances in the understanding of the underlying pathogenic mechanisms in CIDP have brought a number of novel ways of possible intervention for use in CIDP. This review summarizes selected pre-clinical and clinical findings, highlights the importance of using adapted animal models to evaluate the efficacy of novel treatments, and proposes the outlines of future directions to ameliorate the conditions of patients with CIDP.

LPA1 signaling drives Schwann cell dedifferentiation in experimental autoimmune neuritis

BACKGROUND

Lysophosphatidic acid (LPA) is a pleiotropic lipid messenger that addresses at least six specific G-protein coupled receptors. Accumulating evidence indicates a significant involvement of LPA in immune cell regulation as well as Schwann cell physiology, with potential relevance for the pathophysiology of peripheral neuroinflammation. However, the role of LPA signaling in inflammatory neuropathies has remained completely undefined. Given the broad expression of LPA receptors on both Schwann cells and cells of the innate and adaptive immune system, we hypothesized that inhibition of LPA signaling may ameliorate the course of disease in experimental autoimmune neuritis (EAN).

METHODS

We induced active EAN by inoculation of myelin protein 2 peptide (P2_55-78) in female Lewis rats. Animals received the orally available LPA receptor antagonist AM095, specifically targeting the LPA₁ receptor subtype. AM095 was administered daily via oral gavage in a therapeutic regimen from 10 until 28 days post-immunization (dpi). Analyses were based on clinical testing, hemogram profiles, immunohistochemistry and morphometric assessment of myelination.

RESULTS

Lewis rats treated with AM095 displayed a significant improvement in clinical scores, most notably during the remission phase. Cellular infiltration of sciatic nerve was only discretely affected by AM095. Hemogram profiles indicated no impact on circulating leukocytes. However, sciatic nerve immunohistochemistry revealed a reduction in the number of Schwann cells expressing the dedifferentiation marker Sox2 paralleled by a corresponding increase in differentiating Sox10-positive Schwann cells. In line with this, morphometric analysis of sciatic nerve semi-thin sections identified a significant increase in large-caliber myelinated axons at 28 dpi. Myelin thickness was unaffected by AM095.

CONCLUSION

Thus, LPA₁ signaling may present a novel therapeutic target for the treatment of inflammatory neuropathies, potentially affecting regenerative responses in the peripheral nerve by modulating Schwann cell differentiation.

Guillain-Barré Syndrome Presenting as Facial Diplegia after COVID-19 Vaccination: A Case Report

Background: Guillain-Barré Syndrome (GBS) is a rapidly progressive immune-mediated polyneuropathy often associated with an antecedent infectious illness or vaccination. The classic presentation of GBS is characterized by ascending limb weakness and numbness with loss of reflexes. However, atypical variants involving the face and arms or with purely sensory symptoms also exist. In up to 30% of cases, GBS progresses to respiratory failure, with patients requiring mechanical ventilation.

Case Report: We report a case of atypical GBS occurring after Coronavirus disease 2019 (COVID-19) vaccination in an otherwise healthy 38-year-old man. The patient's clinical presentation was characterized by bilateral hand and foot paresthesias, dysarthria, bilateral facial weakness, and an absence of classic ascending limb weakness. Albuminocytological dissociation within the cerebrospinal fluid was suggestive of GBS. The patient received intravenous immunoglobulin therapy, with modest improvement in his symptoms at the time of his discharge from the hospital.

Why Should an Emergency PhysicianBe Aware of This? Patients with GBS are at risk for life-threatening complications, including respiratory failure requiring mechanical ventilation. It is critical for emergency physicians to be aware of the manifold presentations of GBS for early recognition and treatment. This may be of particular importance in the context of a worldwide vaccination campaign in response to the COVID-19 pandemic.

Bortezomib: a proteasome inhibitor for the treatment of autoimmune diseases

Autoimmune diseases (ADs) are conditions in which the immune system cannot distinguish self from non-self and, as a result, tissue injury occurs primarily due to the action of various inflammatory mediators. Different immunosuppressive agents are used for the treatment of patients with ADs, but some clinical cases develop resistance to currently available therapies. The proteasome inhibitor bortezomib (BTZ) is an approved agent for first-line therapy of people with multiple myeloma. BTZ has been shown to improve the symptoms of different ADs in animal models and ameliorated symptoms in patients with systemic lupus erythematous, rheumatoid arthritis, myasthenia gravis, neuromyelitis optica spectrum disorder, Chronic inflammatory demyelinating polyneuropathy, and autoimmune hematologic diseases that were nonresponsive to conventional therapies. Proteasome inhibition provides a potent strategy for treating ADs. BTZ represents a proteasome inhibitor that can potentially be used to treat AD patients resistant to conventional therapies.

Dysregulation of lncRNAs in autoimmune neuropathies

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and Guillain-Barré syndrome (GBS) are inflammatory neuropathies with different clinical courses but similar underlying mechanisms. Long non-coding RNAs (lncRNAs) might affect pathogenesis of these conditions. In the current project, we have selected HULC, PVT1, MEG3, SPRY4-IT1, LINC-ROR and DSCAM-AS1 lncRNAs to appraise their transcript levels in the circulation of CIDP and GBS cases versus controls. Expression of HULC was higher in CIDP patients compared with healthy persons (Ratio of mean expression (RME) = 7.62, SE = 0.72, P < 0.001). While expression of this lncRNA was not different between female CIDP cases and female controls, its expression was higher in male CIDP cases compared with male controls (RME = 13.50, SE = 0.98, P < 0.001). Similarly, expression of HULC was higher in total GBS cases compared with healthy persons (RME = 4.57, SE = 0.65, P < 0.001) and in male cases compared with male controls (RME = 5.48, SE = 0.82, P < 0.001). Similar pattern of expression was detected between total cases and total controls. PVT1 was up-regulated in CIDP cases compared with controls (RME = 3.04, SE = 0.51, P < 0.001) and in both male and female CIDP cases compared with sex-matched controls. Similarly, PVT1 was up-regulated in GBS cases compared with controls (RME = 2.99, SE = 0.55, P vale < 0.001) and in total patients compared with total controls (RME = 3.02, SE = 0.43, P < 0.001). Expression levels of DSCAM-AS1 and SPRY4-IT1 were higher in CIDP and GBS cases compared with healthy subjects and in both sexes compared with gender-matched healthy persons. Although LINC-ROR was up-regulated in total CIDP and total GBS cases compared with controls, in sex-based comparisons, it was only up-regulated in male CIDP cases compared with male controls (RME = 3.06, P = 0.03). Finally, expression of MEG3 was up-regulated in all subgroups of patients versus controls except for male GBS controls. SPRY4-IT could differentiate CIDP cases from controls with AUC = 0.84, sensitivity = 0.63 and specificity = 0.97. AUC values of DSCAM-AS1, MEG3, HULC, PVT1 and LINC-ROR were 0.80, 0.75, 0.74, 0.73 and 0.72, respectively. In differentiation between GBS cases and controls, SPRY4-IT and DSCAM-AS1 has the AUC value of 0.8. None of lncRNAs could appropriately differentiate between CIDP and GBS cases. Combination of all lncRNAs could not significantly enhance the diagnostic power. Taken together, these lncRNAs might be involved in the development of CIDP or GBS.

Neuropathies périphériques associées aux syndromes lymphoprolifératifs : spectre clinique et démarche diagnostique

Lymphoproliferative syndromes (multiple myeloma, Waldenström's disease, chronic lymphocytic leukemia, lymphomas) may be associated with peripheral neuropathies. The mechanism can be dysimmune, associated or not with monoclonal gammopathies; paraneoplastic; infiltrative; or more commonly, iatrogenic or due to vitamin deficiency. The diagnosis can be complex, especially when the neuropathy is the presenting manifestation, requiring a close cooperation between internists and neurologists. The positive diagnosis of the neuropathy is based on a systematic electro-clinical investigation, which specifies the topography and the mechanism of the nerve damage, sometimes reinforced by imaging examinations, in particular, nerve and/or plexus MRI. The imputability of the neuropathy to a lymphoproliferative syndrome is based on a set of arguments including the clinical context (B signs, tumour syndrome), first-line laboratory tests (hemogram, protein electrophoresis, viral serologies, complement), auto-antibodies discussed according to the neuropathy (anti-MAG, anti-gangliosides) and sometimes more invasive examinations (bone marrow or neuro-muscular biopsies).

Assessment of Expression of SOCS Genes in Acquired Immune-Mediated Polyneuropathies

Acquired immune-mediated polyneuropathies are classified to some subtypes among them are acute and chronic inflammatory demyelinating polyradiculoneuropathies (AIDP and CIDP). These two conditions share some common signs and underlying mechanisms. Based on the roles of Suppressor of cytokine signaling (SOCS) genes in the modulation of immune system reactions, these genes might be involved in the pathogenesis of these conditions. We evaluated expression of SOCS1-3 and SOCS5 genes in the leukocytes of 32 cases of CIDP, 19 cases of AIDP and 40 age- and sex-matched controls using real time PCR method. The Bayesian regression model was used to estimate differences in mean values of genes expressions between cases and control group. Expression levels of SOCS1 and SOCS2 were significantly lower in male patients compared with controls. This sex-specific pattern was also observed for SOCS3 down-regulation. Based on the area under curve values in Receiver Operating Characteristics (ROC) curve, diagnostic powers of SOCS1, SOCS2, SOCS3 and SOCS5 genes in the mentioned disorder were 0.61, 0.73, 0.68 and 0.58, respectively. Expression of none of genes was correlated with age of enrolled cases. The current study shows evidences for participation of SOCS genes in the pathophysiology of acquired immune-mediated polyneuropathies.

Outcome measures and biomarkers in chronic inflammatory demyelinating polyradiculoneuropathy: from research to clinical practice

Introduction: Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an immune-mediated syndrome characterized clinically by weakness and/or numbness that evolves over 2 months or more. The heterogeneity of clinical features necessitates an individualized approach to disease monitoring that takes lessons learned from clinical trials and applies them to clinical practice.Areas covered: This review discusses the importance of clinimetrics and biomarkers in CIDP diagnosis and disease monitoring. Highlighted are the challenges of defining responses to immunotherapy, the usefulness, and limitations of utilizing evidence-based clinical outcome measures during routine clinical care, and the evolving understanding of how diagnostic and disease activity biomarkers may reshape our treatment and disease monitoring paradigms.Expert opinion: Although disability and impairment outcome measures are commonly used in CIDP to indicate disease status, the nonspecific nature of these metrics limits the ability to attribute a change in any given metric to a change in CIDP. This interpretive challenge may be magnified by inconsistencies in the direction of change as well as a strong placebo effect. There is a need to improve our understanding of minimally important changes in existing outcome measures as a means to personalize treatment and to better assess disease activity status with biomarker discovery.

Emerging Role of C5 Complement Pathway in Peripheral Neuropathies: Current Treatments and Future Perspectives

The complement system is a key component of innate immunity since it plays a critical role in inflammation and defense against common pathogens. However, an inappropriate activation of the complement system is involved in numerous disorders, including peripheral neuropathies. Current strategies for neuropathy-related pain fail to achieve adequate pain relief, and although several therapies are used to alleviate symptoms, approved disease-modifying treatments are unavailable. This urgent medical need is driving the development of therapeutic agents for this condition, and special emphasis is given to complement-targeting approaches. Recent evidence has underscored the importance of complement component C5a and its receptor C5aR1 in inflammatory and neuropathic pain, indicating that C5a/C5aR1 axis activation triggers a cascade of events involved in pathophysiology of peripheral neuropathy and painful neuro-inflammatory states. However, the underlying pathophysiological mechanisms of this signaling in peripheral neuropathy are not fully known. Here, we provide an overview of complement pathways and major components associated with dysregulated complement activation in peripheral neuropathy, and of drugs under development targeting the C5 system. C5/C5aR1 axis modulators could represent a new strategy to treat complement-related peripheral neuropathies. Specifically, we describe novel C5aR allosteric modulators, which may potentially become new tools in the therapeutic armory against neuropathic pain.

Spinal cord compression from hypertrophic nerve roots in chronic inflammatory demyelinating polyradiculoneuropathy - A case report

Background:

Spinal cord compression secondary to nerve root hypertrophy is often attributed to hereditary neuropathies. However, to avoid misdiagnosis, rare immune-mediated neuropathy such as chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) should not be overlooked. This report presents a case of multilevel nerve root hypertrophy leading to significant cord compression from CIDP.

Case Description:

We report a 56-year-old gentleman with type two diabetes mellitus who presented with subacute cervical cord syndrome following a fall. Mixed upper and lower motor neuron features were noted on examination. Magnetic resonance imaging showed significant pan-spinal proximal nerve root hypertrophy, compressing the cervical spinal cord. Initial radiological opinion raised the possibility of neurofibromatosis type 1 (NF-1), but neurophysiology revealed both axonal and demyelinating changes that were etiologically non-specific. C6 root and sural nerve biopsies taken at cervical decompression displayed striking features suggestive for CIDP. Although NF-1 is the most observed condition associated with root hypertrophy, other important and potentially treatable differentials need to be entertained.

Conclusion:

While rare, CIDP can cause significant spinal cord compression. Furthermore, clinical manifestations of CIDP can mimic those of inherited peripheral neuropathies. Neurologists and neurosurgeons should be aware of this condition to optimize subsequent therapeutic decision-making.

Chronic inflammatory demyelinating polyradiculoneuropathy presenting as predominantly sciatic monomelic neuropathy

Background

Chronic inflammatory demyelinating polyneuropathy (CIDP) is a common yet underdiagnosed cause of potentially treatable chronic sensorimotor neuropathy. The classical form of the disease is characterised by symmetrical weakness in both distal and proximal muscle groups accompanied by sensory dysfunction and diminished tendon reflexes lasting more than 2 months.

Method

The diagnosis of CIDP is supplemented by electrodiagnostic studies and biopsy findings confirming demyelination, in accordance with well-established diagnostic criteria. Atypical presentations of CIDP often pose a diagnostic challenge.

Results

In this paper, we present a case of isolated lower limb involvement due to CIDP to raise awareness of this focal lower limb variant. Of particular, significance is the use of lumbosacral plexus MRI to assist in the diagnosis.

Conclusion

Focal CIDP is an atypical presentation that should be considered in patients presenting with chronic monomelic neuropathy and should be investigated with electrodiagnostic studies, lumbar puncture, nerve biopsy and MRI of the nerve roots and plexuses.

Monoclonal Antibodies as Neurological Therapeutics

Over the last 30 years the role of monoclonal antibodies in therapeutics has increased enormously, revolutionizing treatment in most medical specialties, including neurology. Monoclonal antibodies are key therapeutic agents for several neurological conditions with diverse pathophysiological mechanisms, including multiple sclerosis, migraines and neuromuscular disease. In addition, a great number of monoclonal antibodies against several targets are being investigated for many more neurological diseases, which reflects our advances in understanding the pathogenesis of these diseases. Untangling the molecular mechanisms of disease allows monoclonal antibodies to block disease pathways accurately and efficiently with exceptional target specificity, minimizing non-specific effects. On the other hand, accumulating experience shows that monoclonal antibodies may carry class-specific and target-associated risks. This article provides an overview of different types of monoclonal antibodies and their characteristics and reviews monoclonal antibodies currently in use or under development for neurological disease.

Evaluation of Expression of STAT Genes in Immune-Mediated Polyneuropathies

Immune-mediated polyneuropathies are acquired conditions that can be categorized to acute and chronic forms based on the disease course. Although the basic mechanism of these conditions has not been clarified yet, genes that regulate immune responses are putative contributors in their development. In the current study, we assessed expression of signal transducer and activator of transcription (STAT)1-3 and STAT5a genes in peripheral blood of 51 patients and 40 healthy subjects. Expression of STAT1 was higher in female patients compared with female controls (Posterior Beta = 3.622, P = 0.044). The gender*group interaction was significant for this gene which indicates different direction of association in males and females. Expressions of other STAT genes were not different between cases and controls. The diagnostic power of STAT1 in female subjects was estimated to be 0.72 with sensitivity of 68.75% and specificity of 84.62%. There was no significant correlation either between expression of different STAT genes or between their expression and age of study participants. The current study potentiates STAT1 as a putative factor in the pathophysiology of acquired immune-mediated polyneuropathies in females and suggests conduction of further functional studies to elaborate the molecular mechanism of this contribution.

Successful Nucleoside Analog and Corticosteroid Therapy for Chronic Inflammatory Demyelinating Polyneuropathy in a Patient With Hepatitis B Virus Liver Cirrhosis

Here, we describe the case of a 44-year-old man with chronic hepatitis B virus (HBV) infection, who was admitted with progressive muscle weakness and paresthesia in all extremities. He showed slight icterus. Positive HBV e-antigen test, significant HBV-deoxyribonucleic acid load, hypoalbuminemia, hyperbilirubinemia, mild ascites, and demyelinating peripheral axonal lesions in both sensory and motor nerves led to the diagnosis of Child-Pugh class B HBV cirrhosis with chronic inflammatory demyelinating polyneuropathy. Oral lamivudine, intravenous steroids, calcium, and vitamin D therapy led to a significant recovery of muscle strength within 6 weeks and a gradual return to normal after 24 weeks.

A comparison of IL-17 and IL-34 concentrations in the cerebrospinal fluid of patients with acute inflammatory demyelinating neuropathy and chronic inflammatory demyelinating polyneuropathy

OBJECTIVE

The role of interleukins, such as IL-17 and IL-34, in the pathogenesis of autoimmune diseases has been established in the literature. In the current study, we aimed to identify the concentrations of IL-17 (IL-17A, IL-17F) and IL-34 in the cerebrospinal fluid (CSF) of patients with chronic inflammatory demyelinating polyneuropathy (CIDP) and acute inflammatory demyelinating neuropathy (AIDN).

METHODS

We included in this study 8 patients with CIDP (none of them receiving immunomodulatory or immunosuppressant therapy), 7 patients with Guillain-Barre syndrome (GBS, AIDN), and 7 control subjects. The CIDP and AIDN diagnoses were made by clinical evaluation and electrophysiological investigations according to international criteria. CSF samples were obtained appropriately, and the levels of IL-17A, IL-17F, and IL-34 were measured by ELISA kits.

RESULTS

The concentrations of IL-17A, IL-17F, and IL-34 were higher in those with CIDP and AIDN compared to the controls (p=0.005, p=0.01, and p=0.001, respectively). While IL-34 levels were significantly higher in AIDN patients than in CIDP patients (p=0.04), there were no significant differences between the AIDN and CIDP groups with regard to the levels of IL-17A and IL-17F (p=0.4 and p=0.2, respectively).

CONCLUSION

Our results indicate that IL-17A, IL-17F, and IL-34 levels may have a role in CIDP and AIDN. Furthermore, the difference in the IL-34 levels of patients with AIDN and CIDP may indicate an important difference between the pathogenesis of these two sets of the disease.

Association between chronic inflammatory demyelinating polyneuropathy and gastrointestinal malignancies

Chronic inflammatory demyelinating polyneuropathy (CIDP) is an uncommon and under-recognized immune-mediated disorder of the peripheral nervous system. It is associated with both infectious and non-infectious etiologies and presents in several variant forms. In rare instances, CIDP has been reported in association with gastrointestinal (esophageal, hepatic, colorectal, and pancreatic) malignancies. The diagnosis of malignancy is typically preceded by weeks to months by that of CIDP, though the inverse may also be seen. As with other etiologies of CIDP, cases associated with gastrointestinal malignancies are often treated with corticosteroids, intravenous immunoglobulins, and/or plasma exchange, with improvement or resolution of neurological symptoms in the majority of cases. In this review, we provide a practical overview of CIDP, with an emphasis on recognizing the clinical association between CIDP and gastrointestinal malignancies.

Chronic inflammatory demyelinating polyradiculoneuropathy: can a diagnosis be made in patients not fulfilling electrodiagnostic criteria?

BACKGROUND AND PURPOSE

The aim was to identify the clinical and diagnostic investigations that may help to support a diagnosis of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) in patients not fulfilling the European Federation of Neurological Societies and Peripheral Nerve Society (EFNS/PNS) electrodiagnostic criteria.

METHODS

The data from patients with a clinical diagnosis of CIDP included in a national database were retrospectively reviewed.

RESULTS

In all, 535 patients with a diagnosis of CIDP were included. This diagnosis fulfilled the EFNS/PNS criteria in 468 patients (87.2%) (definite in 430, probable in 33, possible in three, while two had chronic immune sensory polyradiculopathy). Sixty-seven patients had a medical history and clinical signs compatible with CIDP but electrodiagnostic studies did not fulfill the EFNS/PNS criteria for CIDP. These patients had similar clinical features and frequency of abnormal supportive criteria for the diagnosis of CIDP compared to patients fulfilling EFNS/PNS criteria. Two or more abnormal supportive criteria were present in 40 (61.2%) patients rising to 54 (80.6%) if a history of a relapsing course as a possible supportive criterion was also included. Increased cerebrospinal fluid proteins and response to immune therapy most frequently helped in supporting the diagnosis of CIDP. Response to therapy was similarly frequent in patients fulfilling or not EFNS/PNS criteria (87.3% vs. 85.9%).

CONCLUSIONS

Patients with a clinical diagnosis of CIDP had similar clinical findings, frequency of abnormal supportive criteria and response to therapy compared to patients fulfilling EFNS/PNS criteria. The presence of abnormal supportive criteria may help in supporting the diagnosis of CIDP in patients with a medical history and clinical signs compatible with this diagnosis but non-diagnostic nerve conduction studies.

Electrophysiological testing in chronic inflammatory demyelinating polyneuropathy patients treated with subcutaneous immunoglobulin: The Polyneuropathy And Treatment with Hizentra (PATH) study

OBJECTIVE

To assess electrophysiology parameters that can reflect patients' clinical status and show changes in nerve function with treatment, in a study of subcutaneous immunoglobulin in chronic inflammatory demyelinating polyneuropathy.

METHODS

Nerve conduction studies (latency, conduction velocity, conduction block and compound muscle action potential [CMAP] on upper limb median, ulnar, and lower limb peroneal motor nerves) were conducted in the placebo-controlled PATH (Polyneuropathy And Treatment with Hizentra) study of two doses of maintenance subcutaneous immunoglobulin (SCIG) IgPro20 in CIDP.

RESULTS

Averaged proximal latency substantially increased with placebo (+1.1 ms) indicating electrophysiologic deterioration but remained stable with IgPro20 (0.2 g/kg bodyweight [bw]: +0.1 ms; 0.4 g/kg bw: -0.1 ms). Distal latencies were also more prolonged with placebo versus IgPro20. Averaged motor nerve conduction velocity substantially decreased with placebo (-1.6 m/s) versus increasing in both IgPro20 groups (+0.2 m/s and +1.0 m/s, respectively). Conduction block and CMAP amplitudes did not change substantially.

CONCLUSION

These findings support the effectiveness of maintenance IgPro20, as nerve function changed in the direction of increasing nerve dysfunction with placebo but remained stable with ongoing IgPro20 therapy.

SIGNIFICANCE

Electrophysiology testing can support assessment of clinical status in CIDP to determine treatment efficacy.

Comparative Pathology of the Peripheral Nervous System

The peripheral nervous system (PNS) relays messages between the central nervous system (brain and spinal cord) and the body. Despite this critical role and widespread distribution, the PNS is often overlooked when investigating disease in diagnostic and experimental pathology. This review highlights key features of neuroanatomy and physiology of the somatic and autonomic PNS, and appropriate PNS sampling and processing techniques. The review considers major classes of PNS lesions including neuronopathy, axonopathy, and myelinopathy, and major categories of PNS disease including toxic, metabolic, and paraneoplastic neuropathies; infectious and inflammatory diseases; and neoplasms. This review describes a broad range of common PNS lesions and their diagnostic criteria and provides many useful references for pathologists who perform PNS evaluations as a regular or occasional task in their comparative pathology practice.

NK cell markers predict the efficacy of IV immunoglobulins in CIDP

Objective

To assess whether IV immunoglobulins (IVIgs) as a first-line treatment for chronic inflammatory demyelinating polyneuropathy (CIDP) have a regulative effect on natural killer (NK) cells that is related to clinical responsiveness to IVIg.

Methods

In a prospective longitudinal study, we collected blood samples of 29 patients with CIDP before and after initiation of IVIg treatment for up to 6 months. We used semiquantitative PCR and flow cytometry in the peripheral blood to analyze the effects of IVIg on the NK cells. The results were correlated with clinical aspects encompassing responsiveness.

Results

We found a reduction in the expression of several typical NK cell genes 1 day after IVIg administration. Flow cytometry furthermore revealed a reduced cytotoxic CD56^dim NK cell population, whereas regulatory CD56^bright NK cells remained mostly unaffected or were even increased after IVIg treatment. Surprisingly, the observed effects on NK cells almost exclusively occurred in IVIg-responsive patients with CIDP.

Conclusions

The correlation between the altered NK cell population and treatment efficiency suggests a crucial role for NK cells in the still speculative mode of action of IVIg treatment. Analyzing NK cell subsets after 24 hours of treatment initiation appeared as a predictive marker for IVIg responsiveness. Further studies are warranted investigating the potential of NK cell status as a routine parameter in patients with CIDP before IVIg therapy.

Classification of evidence

This study provides Class I evidence that NK cell markers predict clinical response to IVIg in patients with CIDP.

MRI quantifies lumbosacral nerve root and sciatic nerve hypertrophy in chronic inflammatory demyelinating polyradiculoneuropathy

PURPOSE

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a treatable, immune-mediated condition characterised by progressive or relapsing motor and sensory neurological deficits. The diagnosis is based on a combination of clinical, neurophysiological and supportive criteria, but can be challenging. In this study, we quantified the diameter and cross-sectional area of the lumbosacral nerve roots, and explored the imaging characteristics of the sciatic nerves, in patients with CIDP versus healthy controls using MRI.

METHODS

MRI of the lumbosacral plexus and both thighs was performed at 3 T. Orthogonal diameter and cross-sectional area of the lumbosacral nerve roots were measured, along with sciatic nerve cross-sectional area at the mid-thigh level. The MRI appearance of the sciatic nerves was also evaluated qualitatively. All measurements were performed by an observer blinded to the diagnosis.

RESULTS

10 patients with CIDP and 10 healthy controls (age and sex-matched) were studied. Lumbosacral nerve root diameter and cross-sectional area were significantly increased in patients with CIDP compared to controls (mean diameter 6.0 ± 1.1 mm vs 4.8 ± 0.3 mm; p = 0.006), with a high sensitivity (89 %) and specificity (90 %) on ROC analysis. Sciatic nerve cross sectional area was also significantly increased in the CIDP group, and was accompanied by qualitative MRI changes.

CONCLUSIONS

Quantitative MRI reveals significant hypertrophy of the lumbosacral nerve roots and sciatic nerves in patients with CIDP compared to controls. This study provides further evidence for the inclusion of lumbosacral nerve root and sciatic nerve hypertrophy on MRI as a supportive feature in the diagnostic criteria for CIDP.

Increased Levels of IL-34 in Acquired Immune-Mediated Neuropathies

Interleukin (IL)-34 is ligand for the colony-stimulating factor (CSF)-1 receptor. This cytokine has fundamental roles the pathogenesis of a number of autoimmune and neurologic disorders. However, its role in the pathogenesis of acute and chronic inflammatory demyelinating polyneuropathies (AIDP and CIDP) has not been assessed yet. We measured serum levels of IL-34 33 CIDP cases, 16 AIDP cases, and 33 control subjects using commercial ELISA kits. IL-34 levels were significantly higher in both AIDP (44.87 ± 4.38) and CIDP (44.87 ± 4.38) groups compared with healthy subjects (30.10 ± 1.05) (P = 0.046 and P = 0.01, respectively). Differences between female subgroups were insignificant. However, levels of this cytokine were significantly higher in male subjects with CIDP compared with male controls (P = 0.042). Thus, levels of this cytokine might be regarded as biomarkers for these kinds of autoimmune disorders. Future studies are needed to verify these results and find the molecular mechanism of participation of IL-34 in the pathogenesis of AIDP/CIDP.

Immune-Mediated Neuropathies

The immune-mediated neuropathies are a broad category of diseases differentiated by time course, affected nerve fibers, and disease associations. This article spans the common, well-defined inflammatory demyelinating polyradiculoneuropathies (Guillain-Barré syndrome and chronic inflammatory demyelinating polyradiculoneuropathy) to the rarer, acquired demyelinating neuropathy variants (Miller-Fisher syndrome and multifocal motor neuropathy), vasculitic neuropathies, and sensory neuronopathies (dorsal root ganglionopathies). These case studies illustrate the characteristic clinical patterns of the immune-mediated neuropathies encountered in neurologic practice. Recommendations for diagnostic evaluation and treatment approach accompany each case. Prompt recognition of these disorders is imperative; delays in treatment may result in prolonged morbidity and permanent disability.

High Levels of Il-19 in Patients with Chronic Inflammatory Demyelinating Polyneuropathy

Immune-mediated neuropathies include some specific types such as acute and chronic inflammatory demyelinating polyneuropathy (AIDP and CIDP). Previous studies have demonstrated abnormal cellular or humoral immune responses in these conditions. Although aberrant regulation of several cytokines have been reported in AIDP and CIDP, the significance of interleukin 19 (IL-19) in these conditions have not been elucidated yet. In the current study, we assessed serum levels of IL-19 in 12 CIDP patients (female/male ratio, 4/8), 9 AIDP patients (female/male ratio, 3/6), and 27 normal subjects (female/male ratio. 8/19) using commercial ELISA kits. Notably, we detected higher levels of this cytokine in CIDP patients (136.4 ± 8.57 ng/l) compared with both AIDP patients (93.89 ± 2.26 ng/l) and controls (83.78 ± 1.72 ng/l). However, the differences between AIDP patients and controls were not significant. The current study demonstrates the role of IL-19 in the pathogenesis of CIDP and potentiates this cytokine as a biomarker for this condition.

Long-term treatment with subcutaneous immunoglobulin in patients with chronic inflammatory demyelinating polyradiculoneuropathy: a follow-up period up to 7 years

Chronic Inflammatory Demyelinating Polyneuropathy (CIDP) is a rare and heterogeneous acquired sensory-motor polyneuropathy with autoimmune pathogenesis. Intravenous immunoglobulins (IVIG) are a well-established therapy for CIDP: it is well known that at least two-thirds of these patients need these infusions for several years. More recently, Subcutaneous Immunoglobulins (SCIg) have been proved to be effective: this finding has been confirmed either in isolated cases or in few randomized trials. However, it appeared that the longest SCIg treatment follow up lasted no longer than 48 months. We report herein the results of a long-term SCIg treatment with a follow up period up to 7 years (84 months), considering safety, tolerability and patients’ perception of SCIg treatment in a CIDP population. We studied 17 patients (10 M; 7 F) with a diagnosis of CIDP, defined according to the EFNS/PNS criteria, successfully treated with IVIG every 4/6 weeks before being switched to SCIg treatment. Clinical follow-up included, apart from a routinely clinical assessment, the administration of Medical Research Council (MRC) sum-score, the Overall Neuropathy Limitation Scale (ONLS) and the Life Quality Index questionnaire (LQI). The results showed that, in the majority of this pre-selected group of CIDP patients (16/17), SCIg were well tolerated and were preferred over IVIG. Strength and motor functions remained stable or even improved during the long term follow-up (up to 84 months) with benefits on walking capability and resistance, manual activity performances and fatigue reduction.

Assessment of IL-38 Levels in Patients with Acquired Immune-Mediated Polyneuropathies

Acute and chronic inflammatory demyelinating polyneuropathy (AIDP and CIDP) are two types of immune-mediated neuropathies in which abnormal cellular or humoral immune responses have been observed. Although dysregulation of several cytokines has been detected in these disorders, expression of interleukin 38 (IL-38) has not yet been assessed in AIDP and CIDP. In the current study, we evaluated serum concentrations of this member of the IL-1 family of cytokines in 24 patients with CIDP, 13 patients with AIDP and 27 healthy subjects. We detected higher levels of IL-38 in CIDP patients compared with controls. When assessing study subgroups based on gender, there were no significant differences in IL-38 levels among the three female subgroups (P = 0.14). However, the difference among male subgroups was significant (P = 0.010). A Tukey test showed significant differences between male CIDP patients and male controls (P = 0.014). Considering the proposed anti-inflammatory role of IL-38, higher levels of this cytokine in CIDP might reflect the presence of a compensatory mechanism to reduce inflammatory processes in these patients. Further longitudinal assessment of this cytokine is need to test this hypothesis.

RELEVANCE OF DIAGNOSTIC INVESTIGATIONS IN CHRONIC INFLAMMATORY DEMYELINATING POLIRADICULONEUROPATHY: DATA FROM THE ITALIAN CIDP DATABASE

Background and aims to report the clinical features and the relevance of diagnostic investigations in patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). We retrospectively reviewed data from patients with a clinical diagnosis of CIDP included in a national database. Among the 500 included patients with a clinical diagnosis of CIDP, 437 patients (87%) fulfilled the EFNS/PNS criteria for CIDP (definite in 407, probable in 26, possible in four). In 352 patients (86%) motor nerve conduction abnormalities consistent with demyelination were sufficient for the diagnosis of definite CIDP. In 55 patients this diagnosis required the addition of one or two (from probable or from possible CIDP, respectively) supportive tests, while in 20 cases they improved the diagnosis from possible to probable CIDP, seven patients did not change diagnosis. Considering these 85 patients, CSF studies were performed in 79 cases (93%) upgrading the certainty of diagnosis in 59% of examined patients. Sensory nerve conduction studies were performed in 85% of patients with an improvement of diagnosis in 32% of cases. Nerve biopsy and US/MRI exams resulted positive in about 40% of examined patients, but they were performed in few patients (7 patients and 16 patients, respectively). A response to therapy was present in 84% of treated patients (n = 77), contributing to support the diagnosis in 40 patients in whom the other supportive criteria were not sufficient. In most patients with CIDP the diagnosis is possible solely with motor nerve conduction studies while other investigations may help improving the diagnosis in a minority of patients. This article is protected by copyright. All rights reserved.

Evaluation of Quality of Life in Patients With Chronic Inflammatory Demyelinating Polyneuropathy in Iran

OBJECTIVES

In addition to the physical disability in chronic inflammatory demyelinating polyneuropathy (CIDP), various aspects of quality of life (QoL) are affected by the disease. Our goal was to evaluate the QoL in Iranian patients with CIDP and to study the association of clinical and demographic factors with QoL parameters.

METHODS

Twenty-six Iranian patients with CIDP were asked to complete a standardized Persian version of SF-36, and the association of demographic and functional parameters with QoL parameters was assessed.

RESULTS

Sex, living place, and income had no significant effect on QoL. Mean physical composite score was 37.7 ± 9.4, and mean mental composite score was 37.2 ± 15.2 that was lower than similar studies. There was a positive correlation between QoL and muscle strength of different muscle groups [hand (r = 0.41, P = 0.04); hip (r = 0.44, P = 0.02); and foot (r = 0.41, P = 0.04); total manual muscle testing (r = 0.46, P = 0.02)] and a significant negative correlation between the duration of illness and mean physical composite score (r = -0.61, P = 0.00).

CONCLUSIONS

Our patients achieved low scores in both the physical and mental aspects of QoL compared with other studies. We found a significant correlation between the physical domain of the SF-36 score and muscle strength of the hand, hip, and foot muscle group and with total manual muscle testing, suggesting that physical disability is the most crucial factor affecting QoL. Also, there was a significant negative association between the duration of the disease and the physical domain.

Guidelines on the Use of Therapeutic Apheresis in Clinical Practice - Evidence-Based Approach from the Writing Committee of the American Society for Apheresis: The Eighth Special Issue

The American Society for Apheresis (ASFA) Journal of Clinical Apheresis (JCA) Special Issue Writing Committee is charged with reviewing, updating and categorizing indications for the evidence-based use of therapeutic apheresis (TA) in human disease. Since the 2007 JCA Special Issue (Fourth Edition), the committee has incorporated systematic review and evidence-based approaches in the grading and categorization of apheresis indications. This Eighth Edition of the JCA Special Issue continues to maintain this methodology and rigor in order to make recommendations on the use of apheresis in a wide variety of diseases/conditions. The JCA Eighth Edition, like its predecessor, continues to apply the category and grading system definitions in fact sheets. The general layout and concept of a fact sheet that was introduced in the Fourth Edition, has largely been maintained in this edition. Each fact sheet succinctly summarizes the evidence for the use of TA in a specific disease entity or medical condition. The Eighth Edition comprises 84 fact sheets for relevant diseases and medical conditions, with 157 graded and categorized indications and/or TA modalities. The Eighth Edition of the JCA Special Issue seeks to continue to serve as a key resource that guides the utilization of TA in the treatment of human disease.

Membrane property changes in most distal motor axons in chronic inflammatory demyelinating polyneuropathy

INTRODUCTION

Distal nerve terminals, where the blood-nerve barrier is anatomically deficient, are preferentially affected in immune-mediated neuropathies. Excitability alterations near the motor nerve terminals may be more prominent than the nerve trunk in typical chronic inflammatory demyelinating polyneuropathy (CIDP).

METHODS

In 20 patients with typical CIDP, motor nerve excitability testing was performed at the motor point and wrist of the ulnar nerve, and results were compared with those in 20 healthy persons.

RESULTS

Chronic inflammatory demyelinating polyneuropathy patients showed greater threshold changes in hyperpolarizing threshold electrotonus at the motor point (P < .05) but not at the wrist. Strength-duration time constant did not show significant differences between CIDP and controls at both sites.

DISCUSSION

Axonal property changes in CIDP are more prominent in distal portions of axons compared with the nerve trunk, presumably due to salient demyelination near the distal nerve terminals. Motor point excitability measurements could elucidate underlying pathophysiology in immune-mediated neuropathies.

Human leukocyte antigens class II in CIDP spectrum neuropathies

CIDP spectrum encompasses several clinical variants and the reasons of the heterogeneous clinical expression and the variable response to therapy are scarcely known. HLA associations are common in dysimmune conditions. In CIDP, few studies reported no associations or HLA-DR13/DQ6 association in some populations but, to date, a clear confirmed association is lacking. We analyzed expression of HLA-DR and DQ haplotypes in 24 CIDP patients and 216 healthy subject. HLA-DR3 and DR3/DQ2 were significantly more frequent in CIDP patients than in the control group. The DR3 and DR3/DQ2 positive patients present with more frequent relapsing course, worse response to IVIg, higher inflammatory neuropathy sensory sumscore (ISS) and Rotterdam Inflammatory Neuropathy Cause and Treatment Scale (INCAT) than negative patients.