Pain in Chronic Inflammatory Demyelinating Polyradiculoneuropathy: A Systematic Review and Meta-Analysis

Pediatric Chronic Inflammatory Demyelinating Polyneuropathy: Challenges in Diagnosis and Therapeutic Strategies

Chronic inflammatory demyelinating polyneuropathy (CIDP) is a rare autoimmune neurological disorder seen in both pediatric and adult populations. CIDP typically presents with progressive and persistent weakness over at least 4 weeks in addition to sensory symptoms in the extremities. Although CIDP shares common clinical features between children and adults, it sometimes presents as a distinct clinical entity in children that requires close attention and recognition. A major caveat when diagnosing a child with CIDP is the clinical and diagnostic overlap with inherited neuropathies, most commonly Charcot-Marie-Tooth disease (CMT). Demyelinating CMT (dCMT) and CIDP might share similar clinical presentations, and sometimes it might be difficult to differentiate them on the basis of the electrodiagnostic findings or cerebrospinal fluid (CSF) albumino-cytological dissociation. This indeed merits early consideration for genetic testing in patients who do not respond to conventional CIDP therapies. Current treatment options for CIDP include intravenous immunoglobulins (IVIG), corticosteroids (CS), and plasmapheresis (PLEX). The need for novel therapies is essential in instances where patients continue to have symptoms despite the standard therapies or due to adverse effects of long-term use of standard therapies such as CS. This paper reviews the challenges in the diagnosis of CIDP in children and the current as well as novel therapies for CIDP.

Biopsychosocial factors associated with pain management in older adults with limited English proficiency

Chronic pain is a prevalent issue among older adults, and effective communication plays a crucial role in accurately conveying the nature of their pain. However, older immigrant adults with limited English proficiency (LEP) encounter significant challenges in expressing the severity and type of pain they experience, creating additional obstacles in their interactions with healthcare providers. This study explored the experience of managing pain among 26 Farsi-speaking older adults with chronic pain. Semi-structured interviews were conducted and data were analyzed using grounded theory methodology. Using the biopsychosocial framework, three main categories of psychological, social, and biological factors arose from data. Depression, stress, sleep disturbances, lack of social support, health literacy, and misdiagnosis or underdiagnosis affected managing pain among older immigrants with LEP. Providing culturally and linguistically competent healthcare providers, particularly in states with a higher number of LEP immigrants, will help maximize the quality of care for patients with chronic pain.

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.

Sensory Chronic Inflammatory Demyelinating Polyradiculoneuropathy: Neglected Immunotherapy-Responsive Sensory Neuropathy

BACKGROUND AND PURPOSE

To report an improvement with immunotherapy in 34 (85%)/40 patients who required an immunotherapy among 56 patients with sensory chronic inflammatory demyelinating polyradiculoneuropathy (CIDP).

METHODS

Sensory CIDP was diagnosed when two inclusion criteria are met: 1) acquired, chronic progressive or relapsing symmetrical or asymmetrical sensory polyneuropathy that had progressed for >2 months; and 2) definite electrophysiological and/or biopsy evidence of demyelinating neuropathy.

RESULTS

Fifty-six patients with sensory CIDP were identified. Evidence of demyelination was obtained from by the routine motor nerve conduction study (NCS) in 39 (70%) patients, from a nerve biopsy in 10, and from a near-nerve needle sensory NCS in 7 patients. The most prominent laboratory abnormality was a high protein level in the cerebrospinal fluid in 21 (49%) of 43 tested patients. Immunotherapy was required in 41 (79%) of the 52 followed-up patients. An improvement with immunotherapy was observed in 36 (88%)/41 patients. In three patients, motor weakness developed in 5-8 years' follow-up period and so, their diagnosis was changed to CIDP.

CONCLUSIONS

Sensory CIDP is responded to an immunotherapy in 88% of the treated patients. Sensory CIDP was diagnosed by the routine motor NCS in 70% of patients and by a sural nerve biopsy in 18% of patients. Thus, sensory CIDP should be recognized as a treatable CIDP variant among the different types of "idiopathic sensory neuropathy."

Development of Good Manufacturing Practice-Compatible Isolation and Culture Methods for Human Olfactory Mucosa-Derived Mesenchymal Stromal Cells

Demyelination in the central nervous system (CNS) resulting from injury or disease can cause loss of nerve function and paralysis. Cell therapies intended to promote remyelination of axons are a promising avenue of treatment, with mesenchymal stromal cells (MSCs) a prominent candidate. We have previously demonstrated that MSCs derived from human olfactory mucosa (hOM-MSCs) promote myelination to a greater extent than bone marrow-derived MSCs (hBM-MSCs). However, hOM-MSCs were developed using methods and materials that were not good manufacturing practice (GMP)-compliant. Before considering these cells for clinical use, it is necessary to develop a method for their isolation and expansion that is readily adaptable to a GMP-compliant environment. We demonstrate here that hOM-MSCs can be derived without enzymatic tissue digestion or cell sorting and without culture antibiotics. They grow readily in GMP-compliant media and express typical MSC surface markers. They robustly produce CXCL12 (a key secretory factor in promoting myelination) and are pro-myelinating in in vitro rodent CNS cultures. GMP-compliant hOM-MSCs are comparable in this respect to those grown in non-GMP conditions. However, when assessed in an in vivo model of demyelinating disease (experimental autoimmune encephalitis, EAE), they do not significantly improve disease scores compared with controls, indicating further pre-clinical evaluation is necessary before their advancement to clinical trials.

What's New in Neuropathy?

Neuropathic pain presents diagnostic and treatment challenges. Despite recent advances in our understanding of the diagnosis and treatment of neuropathy, much remains to be elucidated. Familiar with neuropathy is the paradox that aberrant nerve signaling causes both sensory loss and pain. Voltage-gated sodium channels play an important role in neuronal electrogenesis and communication among neurons, and their dysregulation leads to hyperexcitability and pain. While numerous validated diagnostic assessment tools are available for neuropathy, patients often experience a diagnostic delay about the cause of their neuropathy. New research is defining more specific types of neuropathy beyond peripheral and central forms. The prevalence of pain varies by type of neuropathy, with chronic idiopathic axonal polyneuropathy associated with the highest proportion of patients experiencing pain. In the majority of types, it exceeds 50%. Gluten neuropathy, a form of peripheral neuropathy, is a new diagnostic consideration. It may require electrochemical conductance testing of hands and feet to test for sudomotor dysfunction. Among those with serologically confirmed gluten sensitivity or celiac disease, gluten neuropathy is a common neurological manifestation and may be addressed at least partially by a gluten-free diet. In Greece, a new neuropathic pain registry was created in 2014 in order to help gather data from real-world neuropathic pain patients. While still in its earliest phase, this registry has already produced demographic and treatment data that suggest suboptimal prescribing and less than recommended use of interventional procedures. Awareness campaigns are underway to encourage more Greek pain clinics to participate in this important registry.

Intravenous Immunoglobulin Treatment Patterns and Outcomes in Patients with Chronic Inflammatory Demyelinating Polyradiculoneuropathy: A US Claims Database Analysis

INTRODUCTION

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a rare progressive or relapsing inflammatory disease. Intravenous immunoglobulin (IVIG) is recommended as a first-line therapy. The aim of this study was to describe real-world treatment patterns and outcomes of patients with CIDP in the Define initiating IVIG treatment.

METHODS

This cohort study used health insurance claims data from the Merative MarketScan Research Databases (2008-2018). Adult patients (≥ 18 years old) with CIDP without prior immunoglobulin treatment were identified using International Statistical Classification of Diseases and Related Health Problems (ICD) codes, and patients subsequently initiating IVIG were included in the analysis. Real-world IVIG treatment patterns and treatment and safety outcomes (assessed via ICD codes) were described.

RESULTS

In total, 3975 patients (median age 58 years) with CIDP who initiated IVIG were identified. After the initial IVIG loading period, patients received IVIG at a median dosing interval of 21 days (quartile [Q]1, Q3: 7, 28), and continued treatment for a median of 129 days (Q1, Q3: 85, 271). After the 2-year follow-up period, 55% of patients had discontinued all IVIG treatment; more than one-half of these discontinuations occurred within 4 months. Diagnoses of impaired functional status were evident in more than 30% of patients at baseline, but at lower rates during follow-up. Rates of new-onset safety outcomes after IVIG treatment were low.

CONCLUSION

This real-world analysis of IVIG treatment patterns and treatment and safety outcomes of patients with CIDP who initiated IVIG highlights the unmet need for improved long-term management. Further research is needed to evaluate the use of functional status measures as endpoints for immunoglobulin treatment effectiveness.

Treatment of CIDP

Chronic inflammatory demyelinating polyneuropathy is a disabling but treatable disorder. However, misdiagnosis is common, and it can be difficult to optimise its treatment. Various agents are used both for first and second line. First-line options are intravenous immunoglobulin, corticosteroids and plasma exchange. Second-line therapies may be introduced as steroid-sparing agents or as more potent escalation therapy. It is also important to consider symptomatic treatment of neuropathic pain and non-pharmacological interventions. We discuss the evidence for the various treatments and explain the practicalities of the different approaches. We also outline strategies for monitoring response and assessing the ongoing need for therapy.

French recommendations for the management of adult & pediatric chronic inflammatory demyelinating polyradiculoneuropathy (CIDP)

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a rare autoimmune disorder of the peripheral nervous system, primarily affecting the myelin sheath. The pathophysiology of CIDP is complex, involving both humoral and cellular immunity. The diagnosis of CIDP should be suspected in patients with symmetrical proximal and distal motor weakness and distal sensory symptoms of progressive onset, associated with decreased/abolished tendon reflexes. Treatments include intraveinous immunoglobulins, steroids and plasma exchange, with usually an induction phase followed by a maintenance therapy with progressive weaning. Treatment should be rapidly initiated to prevent axonal degeneration, which may compromise recovery. CIDP outcome is variable, ranging from mild distal paresthesiae to complete loss of ambulation. There have been several breakthroughs in the diagnosis and management of CIDP the past ten years, e.g. discovery of antibodies against the node of Ranvier, contribution of nerve ultrasound and magnetic resonance imaging to diagnosis, and demonstration of subcutaneous immunoglobulins efficiency. This led us to elaborate French recommendations for the management of adult & pediatric CIDP patients. These recommendations include diagnosis assessment, treatment, and follow-up.

Prevalence and determinants of pain in chronic inflammatory demyelinating polyneuropathy: results from the German INHIBIT registry

INTRODUCTION

Pain, fatigue and depression in chronic inflammatory demyelinating polyneuropathy (CIDP) are often underestimated, as the focus lies on sensorimotor dysfunction and gait instability. The aim of this study was to investigate their prevalence, characteristics and contribution to disability in a prospective cohort of 84 patients with CIDP.

METHODS

Pain, fatigue, depression and quality of life were measured using Pain Detect Questionnaire, Krupp's Fatigue Severity Scale, Beck Depression Inventory-II and German Short-Form-36 Health Survey. Sensorimotor deficits and disability were assessed using the Inflammatory Neuropathy Cause and Treatment overall disability score, the Rasch-built Overall Disability Scale, the Medical Research Council Sum Score and the INCAT-sensory sum-score. The interrelation between the five factors was assessed using analysis of variance and linear regression analysis.

RESULTS

Pain was reported in 62%, mostly of moderate and severe intensity, whereas pain characteristics indicated of neuropathic pain (NP) in 29%. Sensory dysfunction was stronger in NP-patients compared to pain-free patients (p=0.001). Pain of any type, especially NP, was associated with more pronounced fatigue symptoms (p=0.010). Depressive symptoms were more frequent in patients with pain compared to the pain-free patients (61% vs. 33%, p=0.02) and were more severe and frequent in NP-patients than in non-NP (p=0.005). Patients with pain had a worse physical quality of life than pain-free patients (p=0.001).

CONCLUSION

Pain, depression and fatigue are relevant disability factors in CIDP affecting quality of life. Sensory dysfunction is associated with NP. Therefore, evaluation of CIDP-related disability should include pain and sensory function for adequate monitoring of therapeutic interventions.

Contemporary challenges in the diagnosis and management of chronic inflammatory demyelinating polyneuropathy

INTRODUCTION

Despite extensive research, multiple inter-related diagnostic and management challenges remain for chronic inflammatory demyelinating polyneuropathy (CIDP).

AREAS COVERED

A literature review was performed on diagnosis and treatment in CIDP. The clinical features and disease course were evaluated. Investigative techniques, including electrophysiology, cerebrospinal fluid examination, neuropathology, imaging and neuroimmunology, were considered in relation to technical aspects, sensitivity, specificity, availability and cost. Available evidenced-based treatments and those with possible efficacy despite lack of evidence, were considered, as well as current methods for evaluation of treatment effects.

EXPERT OPINION

CIDP remains a clinical diagnosis, supported first and foremost by electrophysiology. Other investigative techniques have limited impact. Most patients with CIDP respond to available first-line treatments and immunosuppression may be efficacious in those who do not. Consideration of the natural history and of the high reported remission rate, of under-recognised associated disabling features, of treatment administration modalities and assessment methods, require enhanced attention.

Adjuvant physical exercise for the management of painful polyneuropathy

INTRODUCTION

Physical exercise appeared to be effective, when implemented as an adjuvant to the pharmacotherapy option, in a variety of painful conditions. Peripheral neuropathic pain (PNP) is very prevalent and affects up to two-thirds of individuals with polyneuropathy (PN), regardless of etiology. The aim of this systematic review was to evaluate the currently available studies that assess adjuvant physical exercise for the management of PNP.

METHODS

A systematic literature search was conducted in the PubMed international database. For the systematic search, three medical subject headings (MeSH) were used. Term A was 'physical exercise' OR 'exercise' OR 'activity' OR 'workout' OR 'training'; term B was 'pain' OR 'painful'; term C was 'neuropathy' OR 'polyneuropathy.' Additionally, three filters were used: human subjects, English language, and full text. The reference lists of eligible papers and relevant reviews were also meticulously searched in order to include further relevant studies. Six papers eligible to be included were identified.

RESULTS

Physical exercise in various forms can be of benefit in the management of PNP when used as an adjuvant to the standard care. Overall, using the American Society of Interventional Pain Physicians (ASIPP) criteria, the current best available evidence exists for both aerobic and muscle strengthening exercise programs (level II evidence). The intensity of the exercise seems to play a significant role, with higher intensity interval training programs being more promising, though this remains to be confirmed in future studies.

CONCLUSIONS

Physical exercise is a promising non-pharmacological intervention for the management of PNP. Future RCTs should be conducted to make a face-to-face comparison of the available exercise treatments with the aim to design specific exercise programs for patients with PNP.

Sudomotor dysfunction in patients with gluten neuropathy

BACKGROUND AND AIM

Gluten neuropathy (GN) is a common neurological manifestation of gluten sensitivity (GS), characterized by serological evidence of GS, while other risk factors for developing neuropathy are absent. The degree of small fiber dysfunction in GN has not been studied in depth to date. Small fiber involvement may lead to pain, thermal perception abnormalities, and sweat gland dysfunction. Sudomotor innervation refers to the cholinergic innervation of the sympathetic nervous system through small fibers in the sweat glands. The aim of our study was to assess the sudomotor function of GN patients.

METHODS

Patients with GN were recruited. Clinical and neurophysiological data were obtained. HLA-DQ genotyping was performed. The skin electrochemical conductance (ESC) was measured with SUDOSCAN^TM.

RESULTS

Thirty-two patients (25 males, mean age 69.5±10.2 years) were recruited. Thirteen patients (40.6%) had abnormal sudomotor function of the hands. Sixteen patients (50%) had abnormal sudomotor function of the feet. Twenty-one patients (65.6%) had abnormal sudomotor function of either the hands or feet. Sudomotor dysfunction did not correlate with the type of neuropathy (length-dependent neuropathy or sensory ganglionopathy), gluten-free diet adherence, severity of neuropathy, and duration of disease or HLA-DQ genotype. No differences in the ESC were found between patients with painful and patients with painless GN.

CONCLUSION

Sudomotor dysfunction affects two-thirds of patients with GN. The lack of correlation between pain and sudomotor dysfunction suggests different patterns of small fiber involvement in patients with GN.

Sensory root demyelination: Transforming touch into pain

The normal feeling of touch is vital for nearly every aspect of our daily life. However, touching is not always felt as touch, but also abnormally as pain under numerous diseased conditions. For either mechanistic understanding of the faithful feeling of touch or clinical management of chronic pain, there is an essential need to thoroughly dissect the neuropathological changes that lead to painful touch or tactile allodynia and their corresponding cellular and molecular underpinnings. In recent years, we have seen remarkable progress in our understanding of the neural circuits for painful touch, with an increasing emphasis on the upstream roles of non-neuronal cells. As a highly specialized form of axon ensheathment by glial cells in jawed vertebrates, myelin sheaths not only mediate their outstanding neural functions via saltatory impulse propagation of temporal and spatial precision, but also support long-term neuronal/axonal integrity via metabolic and neurotrophic coupling. Therefore, myelinopathies have been implicated in diverse neuropsychiatric diseases, which are traditionally recognized as a result of the dysfunctions of neural circuits. However, whether myelinopathies can transform touch into pain remains a long-standing question. By summarizing and reframing the fragmentary but accumulating evidence so far, the present review indicates that sensory root demyelination represents a hitherto underappreciated neuropathological change for most neuropathic conditions of painful touch and offers an insightful window into faithful tactile sensation as well as a potential therapeutic target for intractable painful touch.

Gabapentin versus Pregabalin for management of chronic inflammatory demyelinating polyradiculoneuropathy

INTRODUCTION

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a chronic autoimmune demyelinating peripheral neuropathy that leads to symmetrical muscular weakness, sensory deficit, hyporeflexia, chronic fatigue, and impaired quality of life (QoL). The current study aims to investigate the effects of gabapentin versus pregabalin on pain, sleep disturbances, and QoL in CIDP patients.

METHODS

This clinical trial was conducted on 40 patients diagnosed with CIDP randomly allocated to treatment with 100-500 mg gabapentin (n=20) or 50-300 mg pregabalin (n=20) both co-medicated with 37.5 mg venlafaxine. The dose of gabapentin/pregabalin was adjusted based on the patient's tolerability/response to the treatment. Visual analogue scale (VAS), Pittsburg Sleep Quality Questionnaire and Short Form Health Survey (SF-36) were filled at baseline, within three, six, nine and 12 months after the interventions to assess pain severity, sleep quality and QoL, respectively. The Iranian Registry of Clinical Trials (IRCT) code: IRCT20200217046523N16, https://fa.irct.ir/search/result?query=IRCT20200217046523N16.

RESULTS

Gabapentin revealed a dose-dependent efficacy in pain severity (P-value =0.004, r=0.287), sleep quality (P-value <0.001, r=0.387) and QoL (P-value =0.001, r=-0.378), but pregabalin (P-value >0.05). Co-medication of gabapentin plus venlafaxine could significantly improve sleep quality (P-value =0.009) and QoL (P-value =0.004), but pain severity (P-value =0.796). Pregabalin plus venlafaxine showed statistically significant improvement in pain (P-value =0.046), sleep quality (P-value <0.001) and QoL (P-value <0.001). The comparison of the two medications revealed the superiority of pregabalin in pain relief (P-value >0.001) and QoL (P-value =0.03) to pregabalin.

CONCLUSION

Based on this study, the co-medication of pregabalin and venlafaxine led to remarkable superior outcomes compared to venlafaxine plus gabapentin in the management of pain, sleep quality, and QoL due to CIDP.

European Academy of Neurology/Peripheral Nerve Society guideline on diagnosis and treatment of chronic inflammatory demyelinating polyradiculoneuropathy: Report of a joint Task Force-Second revision

OBJECTIVE

To revise the 2010 consensus guideline on chronic inflammatory demyelinating polyradiculoneuropathy (CIDP).

METHODS

Seventeen disease experts, a patient representative, and two Cochrane methodologists constructed 12 Population/Intervention/Comparison/Outcome (PICO) questions regarding diagnosis and treatment to guide the literature search. Data were extracted and summarized in GRADE summary of findings (for treatment PICOs) or evidence tables (for diagnostic PICOs).

RESULTS

Statements were prepared according to the GRADE Evidence-to-Decision frameworks. Typical CIDP and CIDP variants were distinguished. The previous term "atypical CIDP" was replaced by "CIDP variants" because these are well characterized entities (multifocal, focal, distal, motor, or sensory CIDP). The levels of diagnostic certainty were reduced from three (definite, probable, possible CIDP) to only two (CIDP and possible CIDP), because the diagnostic accuracy of criteria for probable and definite CIDP did not significantly differ. Good Practice Points were formulated for supportive criteria and investigations to be considered to diagnose CIDP. The principal treatment recommendations were: (a) intravenous immunoglobulin (IVIg) or corticosteroids are strongly recommended as initial treatment in typical CIDP and CIDP variants; (b) plasma exchange is strongly recommended if IVIg and corticosteroids are ineffective; (c) IVIg should be considered as first-line treatment in motor CIDP (Good Practice Point); (d) for maintenance treatment, IVIg, subcutaneous immunoglobulin or corticosteroids are recommended; (e) if the maintenance dose of any of these is high, consider either combination treatments or adding an immunosuppressant or immunomodulatory drug (Good Practice Point); and (f) if pain is present, consider drugs against neuropathic pain and multidisciplinary management (Good Practice Point).

European Academy of Neurology/Peripheral Nerve Society guideline on diagnosis and treatment of chronic inflammatory demyelinating polyradiculoneuropathy: Report of a joint Task Force-Second revision

To revise the 2010 consensus guideline on chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). Seventeen disease experts, a patient representative, and two Cochrane methodologists constructed 12 Population/Intervention/Comparison/Outcome (PICO) questions regarding diagnosis and treatment to guide the literature search. Data were extracted and summarized in GRADE summary of findings (for treatment PICOs) or evidence tables (for diagnostic PICOs). Statements were prepared according to the GRADE Evidence-to-Decision frameworks. Typical CIDP and CIDP variants were distinguished. The previous term "atypical CIDP" was replaced by "CIDP variants" because these are well characterized entities (multifocal, focal, distal, motor, or sensory CIDP). The levels of diagnostic certainty were reduced from three (definite, probable, possible CIDP) to only two (CIDP and possible CIDP), because the diagnostic accuracy of criteria for probable and definite CIDP did not significantly differ. Good Practice Points were formulated for supportive criteria and investigations to be considered to diagnose CIDP. The principal treatment recommendations were: (a) intravenous immunoglobulin (IVIg) or corticosteroids are strongly recommended as initial treatment in typical CIDP and CIDP variants; (b) plasma exchange is strongly recommended if IVIg and corticosteroids are ineffective; (c) IVIg should be considered as first-line treatment in motor CIDP (Good Practice Point); (d) for maintenance treatment, IVIg, subcutaneous immunoglobulin or corticosteroids are recommended; (e) if the maintenance dose of any of these is high, consider either combination treatments or adding an immunosuppressant or immunomodulatory drug (Good Practice Point); and (f) if pain is present, consider drugs against neuropathic pain and multidisciplinary management (Good Practice Point).

Neurological Causes of Chest Pain

PURPOSE OF REVIEW

Chest pain is a very common presenting complaint among patients in the hospital, a large proportion of whom have non-cardiac chest pain (NCCP). Neurological causes of NCCP have not been previously reviewed although several causes have been identified.

RECENT FINDINGS

Chest pain has been reported as a symptom of multiple neurological conditions such as migraine, epilepsy, and multiple sclerosis, with varying clinical presentations. The affected patients are often not formally diagnosed for long periods of time due to difficulties in recognizing the symptoms as part of neurological disease processes. This paper will briefly summarize well-known etiologies of chest pain and, then, review neurological causes of NCCP, providing an overview of current literature and possible pathophysiologic mechanisms.

Pharmacological Management of Painful Peripheral Neuropathies: A Systematic Review

Introduction

Peripheral neuropathic pain (PNP) arises either acutely or in the chronic phase of a lesion or disease of the peripheral nervous system and is associated with a notable disease burden. The management of PNP is often challenging. The aim of this systematic review was to evaluate current evidence, derived from randomized controlled trials (RCTs) that have assessed pharmacological interventions for the treatment of PNP due to polyneuropathy (PN).

Methods

A systematic search of the PubMed database led to the identification of 538 papers, of which 457 were excluded due to not meeting the eligibility criteria, and two articles were identified through screening of the reference lists of the 81 eligible studies. Ultimately, 83 papers were included in this systematic review.

Results

The best available evidence for the management of painful diabetic polyneuropathy (DPN) is for amitriptyline, duloxetine, gabapentin, pregabalin and venlafaxine as monotherapies and oxycodone as add-on therapy (level II of evidence). Tramadol appears to be effective when used as a monotherapy and add-on therapy in patients with PN of various etiologies (level II of evidence). Weaker evidence (level III) is available on the effectiveness of several other agents discussed in this review for the management of PNP due to PN.

Discussion

Response to treatment may be affected by the underlying pathophysiological mechanisms that are involved in the pathogenesis of the PN and, therefore, it is very important to thoroughly investigate patients presenting with PNP to determine the causes of this neuropathy. Future RCTs should be conducted to shed more light on the use of pharmacological approaches in patients with other forms of PNP and to design specific treatment algorithms.

Electronic supplementary material

The online version of this article (10.1007/s40122-020-00210-3) contains supplementary material, which is available to authorized users.

Non-Pharmacological Management of Painful Peripheral Neuropathies: A Systematic Review

INTRODUCTION

Peripheral neuropathic pain (PNP) is defined as the neuropathic pain that arises either acutely or in the chronic phase of a lesion or disease affecting the peripheral nervous system. PNP is associated with a remarkable disease burden, and there is an increasing demand for new therapies to be used in isolation or combination with currently available treatments. The aim of this systematic review was to evaluate the current evidence, derived from randomized controlled trials (RCTs) that assess non-pharmacological interventions for the treatment of PNP.

METHODS

After a systematic Medline search, we identified 18 papers eligible to be included.

RESULTS

The currently best available evidence (level II of evidence) exist for painful diabetic peripheral neuropathy. In particular, spinal cord stimulation as adjuvant to conventional medical treatment can be effectively used for the management of patients with refractory pain. Similarly, adjuvant repetitive transcranial magnetic stimulation of the motor cortex is effective in reducing the overall pain intensity, whereas adjuvant static magnetic field therapy can lead to a significant decrease in exercise-induced pain. Weaker evidence (level III of evidence) exists for the use of acupuncture as a monotherapy and neurofeedback, either as an add-on or a monotherapy approach, for treatment of painful chemotherapy-induced peripheral neuropathy CONCLUSIONS: Future RCTs should be conducted to shed more light in the use of non-pharmacological approaches in patients with PNP.

Repetitive Magnetic Stimulation for the Management of Peripheral Neuropathic Pain: A Systematic Review

INTRODUCTION

Repetitive magnetic stimulation (rMS) is a safe and well-tolerated intervention. Transcranial magnetic stimulation (TMS) is used for the treatment of depression and for the treatment and prevention of migraine. Over the last few years, several reports and randomised controlled studies of the use of rMS for the treatment of pain have been published. The aim of this systematic review was to identify the available literature regarding the use of rMS in the treatment of peripheral neuropathic pain.

METHODS

After a systematic Medline search we identified 12 papers eligible to be included in this review.

RESULTS

The majority of the studies were on patients with phantom limb pain, followed by radiculopathy, plexopathy, post-traumatic pain and peripheral neuropathy. The treatment protocols vary significantly from study to study and, therefore, pooling the results together is currently difficult. However, rMS has a definite immediate effect in pain relief which, in the majority of studies, is maintained for a few weeks.

CONCLUSION

rMS seems to be a promising intervention in the treatment of peripheral neuropathic pain. Further research is in the field is needed. Use of neuronavigation might increase the precision of stimulation and subsequently its effectiveness.

Prognostic factor of poor outcome in anti-MAG neuropathy: clinical and electrophysiological analysis of a French Cohort

BACKGROUND

Anti-MAG polyneuropathy (anti-MAG PN) is an immune-mediated peripheral sensorimotor neuropathy characterized by distal demyelination and ataxia. However, this disorder, unlike other immune-mediated neuropathies, is difficult to treat in most cases.

METHOD

We retrospectively collected all anti-MAG PN patients followed in two hospitals for a period of 12 years to determine prognostic factors, especially those that indicated a good response to the various therapeutic strategies used.

RESULTS

Forty-seven patients were included in the study; of these, 61% had a classical 'distal demyelinating pattern', 34.2% had a 'CIDP-like pattern', and the others had an 'axonal pattern'. The most commonly used treatments were intravenous immunoglobulin (IVIg) as the first-line treatment and rituximab as the second- or third-line treatment. No prognostic factor was identified for IVIg, but electrophysiological parameters at onset were better in patients with a good response to rituximab than in non-responder patients, even though mild or high disability was observed in nearly half the patients at last examination.

CONCLUSION

Even though disability seems to progress in most cases despite the treatments used, our results suggest that an early electrophysiological reduction in sensory nerves could be considered a 'red flag' for the prompt initiation of rituximab to try to delay long-term disability.