Physical training and fatigue, fitness, and quality of life in Guillain-Barré syndrome and CIDP

Many patients with Guillain-Barré syndrome (GBS) and chronic inflammatory demyelinating polyneuropathy (CIDP) experience excessive fatigue, which may persist for years and reduce quality of life. The authors performed a 12-week study of bicycle exercise training in 20 patients with severe fatigue, 16 with relatively good recovery from GBS, and 4 with stable CIDP. Training seemed well tolerated, and self-reported fatigue scores decreased 20% (p = 0.001). Physical fitness, functional outcome, and quality of life were improved.     

Nerve conduction studies in relation to residual fatigue in Guillain-Barré syndrome

Many Guillain-Barré syndrome (GBS) and Chronic Inflammatory Demyelinating Polyneuropathy (CIDP) patients recover well, but suffer from excessive fatigue, which may persist for years and reduce the quality of life considerably. In order to determine whether residual subclinical peripheral nerve dysfunction is a possible underlying mechanism of fatigue, we performed standardized nerve conduction (NC) studies in 16 fatigued patients, mean 6.5 years after diagnosis. Thirteen were relatively well recovered from GBS and 3 had stable CIDP. In contrast to CIDP, most NC values in GBS patients were remarkably restored and within normal values.No correlations were found between the electrophysiological findings and the fatigue scores,muscle strength, or functional scores. This study demonstrates that fatigue in GBS is not explained by residual nerve dysfunction, using conventional NC measurements.     

Analysis of data from the CDC/FDA Vaccine Adverse Event Reporting System (1990-2009) on Guillain-Barre syndrome after hepatitis vaccination in the USA

We used data from the Vaccine Adverse Event Reporting System, supplemented by additional data provided by the Center for Biologics Evaluation and Research, to identify 189 patients with Guillain–Barré syndrome (GBS) reported after hepatitis vaccination with a mean age of 30.65 years, affecting men and women equally. Among vaccinated patients, 133 (70%) developed GBS within six weeks, 30 (15.9%) after six weeks, and for the remaining 26 (13.7%), the time between GBS occurrence and vaccination was not specified. The reporting rate of post-hepatitis vaccine GBS is approximately 3.4 cases per one million vaccinations, which is in the range expected in the general population. The unbalanced distribution of reports in the first six weeks after vaccination suggests that some cases of GBS may be triggered by vaccination. Nonetheless, the low incidence of hepatitis vaccine-associated GBS, and the dramatic incidence reduction of hepatitis and its complications after vaccination, support the current guidelines for vaccination.     

Long‐term outcome of Guillain‐Barré syndrome in children

The objective of this study is to determine the long‐term outcome and consequences of Guillain‐Barré syndrome (GBS) in children. This is an observational cross‐sectional cohort study of children diagnosed with GBS (0–18 years old) at the Sophia Children's Hospital in Rotterdam from 1987 to 2009. All patients were invited for a structured interview, questionnaires, and full neurologic exam to record their current clinical condition focused on complaints and symptoms, neurological deficits, disabilities, behavior, and quality of life. Thirty‐seven patients participated, 23 were now adults, with a median age of 20 years (range 4–39 years) and a median follow‐up time of 11 years (range 1–22 years). Residual complaints were reported by 24 (65%) patients, including paresthesias (38%), unsteadiness of gait in the dark (37%), painful hands or feet (24%), and severe fatigue (22%). Four patients had severe neurological deficits, including facial diplegia and limb weakness. Two patients had had a recurrence of GBS. In 10 patients (26%), GBS had a negative impact on their school career. Questionnaires identified a wide range of behavioral problems. Quality of life was below normal on the subscale vitality, and above normal on the subscales social functioning and positive emotions in the adult group. Most children show good recovery of neurological deficits after GBS, but many have persisting long‐term residual complaints and symptoms that may lead to psychosocial problems interfering with participation in daily life.     

Chronic inflammatory demyelinating polyneuropathy and ventilatory failure: report of seven new cases and review of the literature

Živković SA, Peltier AC, Iacob T, Lacomis D. Chronic inflammatory demyelinating polyneuropathy and ventilatory failure: report of seven new cases and review of the literature.
Acta Neurol Scand: 2011: 124: 59–63.
© 2010 John Wiley & Sons A/S. Background – Ventilatory involvement is rarely reported in chronic inflammatory demyelinating polyneuropathy (CIDP), but small prospective studies showed frequent involvement of phrenic nerves, which is usually overshadowed by severe limb weakness. Objectives – To report the clinical features of CIDP associated with ventilatory failure. Results – There were seven patients (43% women), with a mean age of 58.6 (range 38–82). The clinical courses were relapsing in five and progressive in two. Four patients had an initial event simulating Guillain–Barre syndrome (GBS). Ventilatory failure was recurrent in three patients. Five patients had full or nearly complete recoveries; one still requires nocturnal ventilation; and one died (14%) of myocardial infarction while still requiring mechanical ventilation. Conclusions– Clinical ventilatory dysfunction in CIDP is usually not an indicator of poor prognosis, and many patients recover without significant permanent disability. The mortality rate is similar to intubated patients with GBS. Patients with cardiopulmonary comorbidities and acute GBS‐like onset of CIDP may be at higher risk of ventilatory failure which typically responds to ‘standard’ treatments of CIDP. Larger prospective studies are needed to define the prevalence, clinical spectrum and significance of ventilatory involvement in CIDP and to establish guidelines for evaluation and treatment.     

Employment status of patients with chronic inflammatory demyelinating polyradiculoneuropathy

It has been previously shown that patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) who are unemployed or retired have worse quality of life. The aim of this study was to assess predictors of early retirement in CIDP. One hundred five patients with CIDP were included. Following measures were used: questionnaire on employment status, Medical Research Council Sum Score, INCAT disability score, Beck Depression Inventory, and Krupp's Fatigue Severity Scale. At the moment of testing, 2% of patients were students, 15% were employed, 9% were unemployed due to CIDP, 9% were unemployed but not due to CIDP, 28% were retired early due to disability caused by CIDP, and finally 37% were in old‐age pension. Mean age when patients retired due to CIDP was 50 ± 8 years. Mean time from CIDP onset to retirement was 2.7 ± 2.3 years. Older age at onset, lower education, and more severe weakness at the time of diagnosis were significant predictors of early retirement due to CIDP. Retired patients were 12 times more likely to suffer from depression, compared to employed patients (OR = 12.2, 95% CI = 1.41‐100, P < 0.01), and eight times more likely to have fatigue (OR = 8.2, 95% CI = 1.89‐35.82, P < 0.01). Older patients with lower education and more severe weakness at the time of diagnosis were most likely retired due to CIDP. Early retirement was associated with depression and fatigue. Therefore, maintaining employment should be an important aim in the management of CIDP patients.     

Acute‐onset chronic inflammatory demyelinating polyneuropathy: An electrodiagnostic study

Introduction: Acute‐onset chronic inflammatory demyelinating polyneuropathy (A‐CIDP) is an increasingly recognized CIDP subtype. Differentiating A‐CIDP from Guillain–Barré syndrome (GBS) is challenging but important, because there are different treatment outcomes. Methods: We report 3 patients with A‐CIDP who were initially diagnosed with severe GBS but were later confirmed to have CIDP based on their clinical course and electrodiagnostic (EDx) studies. We also report on the long‐term treatment of these patients and review the literature on EDx studies in this syndrome. Results: Three patients were initially diagnosed with GBS and responded to treatment. However, all 3 had arrest in improvement or deterioration during their rehabilitation phases. EDx studies showed prominent demyelinating changes many months after the initial presentation. All responded very well to immunotherapy. Conclusion: Although several features may suggest the diagnosis of A‐CIDP at initial presentation, close follow‐up of GBS patients during the recovery phase is also needed for accurate diagnosis. EDx studies may distinguish patients with A‐CIDP from GBS patients. Muscle Nerve 52 : 900–905, 2015     

Conduction velocity distribution in neurologically well-recovered but fatigued Guillain-Barré syndrome patients

Many patients with Guillain-Barré syndrome (GBS) and chronic inflammatory demyelinating polyneuropathy (CIDP) suffer from excessive fatigue. To assess whether this fatigue might be related to changes in slow-conducting nerve fibers, we determined the conduction velocity distribution (CVD) in the median nerve. Thirteen fatigued but neurologically well-recovered GBS patients, 2 fatigued and stable CIDP patients, and 19 healthy controls participated in this study. Conventional maximal nerve conduction velocities (NCVs) did not show differences between GBS patients and healthy controls. However, in both GBS and CIDP patients the CVD was altered, showing significant narrowing of the velocity distribution with loss of the fastest- and slowest-conducting fibers. These changes were most pronounced in the subgroup of patients with the lowest fatigue scores. We therefore conclude that the observed CVD changes in patients are not likely to contribute to persisting complaints of fatigue after GBS.     

Altered cerebrospinal fluid index of prealbumin, fibrinogen, and haptoglobin in patients with Guillain-Barré syndrome and chronic inflammatory demyelinating polyneuropathy

Zhang H‐L, Zhang X‐M, Mao X‐J, Deng H, Li H‐F, Press R, Fredrikson S, Zhu J. Altered cerebrospinal fluid index of prealbumin, fibrinogen, and haptoglobin in patients with Guillain–Barré syndrome and chronic inflammatory demyelinating polyneuropathy.
Acta Neurol Scand: 2012: 125: 129–135.
© 2011 John Wiley & Sons A/S. Objectives – Guillain–Barré syndrome (GBS) and chronic inflammatory demyelinating polyneuropathy (CIDP) are autoimmune diseases of the peripheral nervous system. A clinical hallmark of GBS and CIDP is the albumino‐cytologic dissociation in the cerebrospinal fluid (CSF). Changes in the CSF levels of proteins other than albumin in patients with GBS and CIDP are not as well studied. If altered, aberrant levels of CSF proteins may render it possible to establish useful biomarkers for GBS and CIDP. Materials and methods – Enzyme‐linked immunosorbent assay (ELISA) was used to measure the levels of prealbumin, fibrinogen, haptoglobin, apolipoprotein E, apolipoprotein A4 in both CSF and plasma samples from 19 patients with GBS and eight with CIDP, 24 controls with multiple sclerosis (MS) as well as 20 patients with other non‐inflammatory neurological disorders (OND). Results – The levels of prealbumin in both the plasma and the CSF were elevated in patients with GBS and MS compared with the controls. The higher levels of fibrinogen were seen in the CSF of patients with GBS and CIDP, but not in the plasma. The levels of CSF prealbumin and fibrinogen, measured by the CSF index of these proteins, were lower in patients with GBS and that of fibrinogen in patients with CIDP compared with controls with OND. Haptoglobin levels in the CSF rather than in the plasma were higher in patients with GBS and CIDP than in controls. The CSF haptoglobin index was higher in patients with CIDP and MS, but not in those with GBS. No correlation was found between levels of CSF proteins and clinical parameters in patients with GBS and CIDP. Conclusions – Our data provide preliminary evidence that GBS is associated with low CSF index levels of prealbumin and fibrinogen, but normal levels of haptoglobin, whereas CIDP is associated with normal CSF index levels of prealbumin, low fibrinogen, and high levels of haptoglobin. Further studies are needed to identify the underlying mechanisms behind these CSF protein alterations and to clarify whether prealbumin, fibrinogen, and haptoglobin can serve as useful biomarkers for GBS and CIDP.     

Health‐related quality of life in Guillain‐Barré syndrome patients: a systematic review

Guillain‐Barré syndrome (GBS) encompasses a broad spectrum of health‐related quality of life (HRQL) determinants, including mobility, fatigue, pain, and depression. We systematically reviewed the literature on functional outcome domains in which GBS patients experience limitations in the short and long terms and evaluated determinants of HRQL in GBS patients. MEDLINE and EMBASE were systematically searched by two independent reviewers for articles covering HRQL data of GBS patients. Of 730 abstracts screened, 17 articles covering data of 14 studies matched the selection criteria. The included articles showed that many GBS patients experienced physical limitations, even years after the acute phase of the disease, while results were inconsistent for perceived levels of pain, fatigue, and general mental well‐being. Only three papers covered HRQL assessments at more than one time point, generally showing large improvements in HRQL in the first year after GBS onset, but not thereafter. We appraised the methodological quality of included studies using a 13‐item checklist; none of the articles fulfilled all items and only seven articles presented data on correlations between HRQL and determinants. In conclusion, the majority of studies on HRQL in GBS patients are cross‐sectional and of low methodological quality. This paper provides guidance for much needed high‐quality studies on patterns of patient‐perceived recovery after GBS onset.     

Impairment measures versus inflammatory RODS in GBS and CIDP: a responsiveness comparison

This study aimed to ‘define responder’ through the concept of minimum clinically important differences using the individually obtained standard errors (MCID‐SE) and a heuristic ‘external criterion’ responsiveness method in patients with Guillain‐Barré syndrome (GBS) and chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). One hundred and fourteen newly diagnosed or relapsing patients (GBS: 55, CIDP: 59) were serially examined (1‐year follow‐up). The inflammatory Rasch‐built overall disability scale (I‐RODS), Rasch‐transformed MRC sum score (RT‐MRC), and Rasch‐transformed modified‐INCAT‐sensory scale (RT‐mISS) were assessed. Being‐a‐responder was defined as having a MCID‐SE cut‐off ≥1.96. Also, the correlations between patients' scores on each scale and the EuroQoL health‐status ‘thermometer’ (external criterion) were determined (higher correlation indicated better responsiveness). In both diseases, the SEs showed a characteristic ‘U’‐shaped dynamic pattern across each scales' continuum. The number of patients showing a meaningful change were higher for the I‐RODS > RT‐MRC > RT‐mISS and were in GBS higher than CIDP patients. The MCID‐SE concept using Rasch‐transformed data demonstrated an individual pattern of ‘being‐a‐responder’ in patients with immune‐mediated neuropathies, and the findings were validated by the external criterion responsiveness method. The I‐RODS showed greater responsiveness compared with the MRC and INCAT‐sensory scales, and its use is therefore recommended in future trials in GBS and CIDP.     

Acute‐onset chronic inflammatory demyelinating polyneuropathy with cranial nerve involvement,dysautonomia, respiratory failure,and autoantibodies

We examined a 27‐year‐old woman who developed rapidly progressive quadriplegia and acute respiratory failure that required mechanical ventilation in the intensive care unit. It was unclear whether this was a presentation of Guillain–Barré syndrome (GBS) or acute‐onset chronic inflammatory demyelinating polyradiculoneuropathy (A‐CIDP). Remarkable features included multiple cranial nerve involvement, respiratory failure, dysautonomia, and skin manifestations. Several autoantibodies were elevated, including antinuclear (ANA), anticardiolipin (aCL), thyroid, and calcium‐sensing receptor (CaSR) autoantibodies. The patient was initially diagnosed with GBS and treated with intravenous immunoglobulin (IVIg). After almost complete recovery, relapse with quadriplegia and respiratory failure was observed 12 weeks after motor symptom onset. She then received IVIg and steroid pulse therapy followed by maintenance oral methylprednisolone and plasma exchange. She recovered completely 4 months after the relapse. The further clinical and serological course was consistent with systemic lupus erythematosus (SLE)‐associated CIDP. Herein we evaluate the association between A‐CIDP and some biological markers of autoimmunity. Muscle Nerve, 2010     

The long‐term functional status in patients with Guillain‐Barré syndrome

Background and purpose: The purpose of this study was to analyse the long‐term impact of Guillain‐Barré syndrome (GBS) on quality of life, and the relationship between clinical variables at disease onset and symptoms at follow‐up to general health status. Methods: Forty‐two GBS patients were examined at median 6 years after disease onset and were compared with 50 healthy controls. The fatigue severity scale (FSS), visual analogue scale (VAS) for pain, disability rating index (DRI) and medical outcome study 36‐item short‐form health status scale (SF‐36) were applied. Variables at onset and symptoms at follow‐up were correlated with outcome measurements in GBS. Results: VAS [2.9 (SD 3.3) vs. 1.5 (SD 1.9); P = 0.01] and DRI [2.5 (SD 2.1) vs. 1.0 (SD 1.5); P < 0.001] were significantly higher in patients with GBS, compared with healthy controls. Decreased physical functioning and general health were found on SF‐36. Differences between GBS patients with shorter (<6 years) and longer (≥6 years) follow‐up after onset were not found. Conclusions: Relatively independent from various variables at onset, patients with GBS seem to have a reduced quality of life and functioning, and the distress seems to have become persistent after the first few years with improvement following the acute disease.     

Anti‐ganglioside antibodies in Guillain–Barré syndrome and chronic inflammatory demyelinating polyneuropathy in Chinese patients

Introduction: In this study we investigated the relationships between anti‐ganglioside antibodies and Guillain–Barré syndrome (GBS) and chronic inflammatory demyelinating polyneuropathy (CIDP). Methods: Samples from 48 Chinese patients diagnosed with GBS and 18 patients diagnosed with CIDP were retrospectively reviewed. Results: In the GBS patients, 62.5% were classified as having acute inflammatory demyelinating polyneuropathy (AIDP), 27.1% were found to have acute motor axonal neuropathy (AMAN), and 10.4% were unclassified. Serum IgG anti‐ganglioside antibodies were detected in 46.2% of the AMAN patients and in 6.7% of the AIDP patients (P < 0.05); 5.6% of the 18 CIDP patients were IgG antibody positive, and 27.8% were IgM antibody positive. Facial palsy and sensory impairment were significantly associated with IgM antibodies. Conclusions: These results suggest that IgG anti‐GM1 antibodies are associated with AMAN, but not with AIDP, and that IgM antibodies against GM1, GM2, and GM3 are associated with facial nerve palsy. Muscle Nerve 55 : 470–475, 2017     

Risk factors for Guillain-Barré syndrome

In 100 cases of Guillain-Barré syndrome (GBS) reported from 10 metropolitan areas to the Centers for Disease Control (CDC) after the 1976-77 influenza vaccination campaign and matched associate or spouse controls, we searched for risk factors for GBS other than A/New Jersey/1976 influenza vaccination and acute respiratory infection. The 47 vaccinated cases recalled influenza vaccination in past years less frequently than did controls (p less than 0.025). Cases and controls did not differ in the number of previous vaccinations or in interval from last vaccination. Cases also gave a history of allergy less frequently than controls. There were no other significant differences.     

T cell reactivity to P0, P2, PMP-22, and myelin basic protein in patients with Guillain-Barre syndrome and chronic inflammatory demyelinating polyradiculoneuropathy

Objectives: It has been suggested that autoimmunity to peripheral myelin proteins is involved in the pathogenesis of Guillain-Barré syndrome (GBS) and chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). We aimed to compare reactivity of peripheral blood mononuclear cells (PBMC) to antigens of peripheral myelin proteins in patients with GBS and patients with CIDP with that of healthy controls and patients with other non-immune mediated neuropathies (ON). Methods: We prepared PBMC from blood from 83 healthy controls and from 64 patients with GBS, 54 with CIDP, and 62 with ON. PBMC were tested in antigen specific proliferation assays against peptides from myelin proteins P0, P2, PMP22, and myelin basic protein (MBP), which is identical to myelin P1, and against whole human MBP. Interferon-gamma (IFN-γ) and interleukin (IL)-5 enzyme linked immunospot (ELISPOT) assays were also performed in some subjects to assess spontaneous and peripheral myelin antigen specific PBMC cytokine secretion. Results: Antigen specific PBMC proliferation assays showed no significant elevation of peptide specific T cell responsiveness in patients with GBS or CIDP compared with healthy controls or patients with ON. Levels of spontaneous ELISPOT IFN-γ secretion were increased in patients with GBS and significantly increased in those with CIDP compared with healthy controls and patients with ON. No convincing differences in antigen specific ELISPOT IFN-γ secretion levels to individual peptides were detectable in patients with GBS. The proportion of patients with CIDP with an increased number of PBMC producing IFN-γ in response to peptide PMP-22_51–64 was significantly increased compared with healthy controls and patients with ON. No significant differences in antigen specific ELISPOT IL-5 secretion levels were detectable in patients with GBS or CIDP compared with controls, but levels of spontaneous IL-5 secretion were significantly higher in patients with CIDP than in healthy controls or patients with ON. Conclusions: Although the lack of significantly increased antigen specific PBMC proliferation in GBS and CIDP does not support a role for T cells, the more sensitive ELISPOT technique detected increased numbers of PBMC secreting IFN-γ spontaneously in 25% of patients with GBS, providing further evidence for a role of T cells in the immunopathology of GBS. Increased numbers of spontaneous IFN-γ and IL-5 secreting cells, and increased IFN-γ secretion in response to PMP-22_51–64, in patients with CIDP provide further evidence for a role of myelin specific T cells in CIDP.     

A retrospective study of the relation between vaccination and occurrence of seizures in Dravet syndrome

Dravet syndrome is a severe epileptic encephalopathy starting in the first year of life. Mutations in SCN1A can be identified in the majority of patients, and epileptic seizures in the setting of fever are a clinical hallmark. Fever is also commonly seen after vaccinations and provocation of epileptic seizures by vaccinations in patients with Dravet syndrome has been reported, but not systematically assessed. In a retrospective evaluation of 70 patients with Dravet syndrome and SCN1A mutations, seizures following vaccinations were reported in 27%. In 58% of these patients vaccination-related seizures represented the first clinical manifestation. The majority of seizures occurred after DPT vaccinations and within 72 h after vaccination. Two-thirds of events occurred in the context of fever. Our findings highlight seizures after vaccinations as a common feature in Dravet syndrome and emphasize the need for preventive measures for seizures triggered by vaccination or fever in these children.     

Comparing the NIS vs. MRC and INCAT sensory scale through Rasch analyses

We performed a comparison between Neuropathy Impairment Scale‐sensory (NISs) vs. the modified Inflammatory Neuropathy Cause and Treatment sensory scale (mISS), and NIS‐motor vs. the Medical Research Council sum score in patients with Guillain‐Barré syndrome (GBS), chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), and IgM monoclonal gammopathy of undetermined significance‐related polyneuropathy (MGUSP). The ordinal data were subjected to Rasch analyses, creating Rasch‐transformed (RT)‐intervals for all measures. Comparison between measures was based on validity/reliability with an emphasis on responsiveness (using the patient's level of change related to the individually obtained varying SE for minimum clinically important difference). Eighty stable patients (GBS: 30, CIDP: 30, and MGUSP: 20) were assessed twice (entry: two observers; 2–4 weeks later: one observer), and 137 newly diagnosed or relapsing patients (GBS: 55, CIDP: 59, and IgM‐MGUSP: 23) were serially examined with 12 months follow‐up. Data modifications were needed to improve model fit for all measures. The sensory and motor scales demonstrated approximately equal and acceptable validity and reliability scores. Responsiveness scores were poor but slightly higher in RT‐mISS compared to RT‐NISs. Responsiveness was equal for the RT‐motor scales, but higher in GBS compared to CIDP; responsiveness was poor in patients with MGUSP, suggesting a longer duration of follow‐up in the latter group of patients.     

Defective Fas-mediated T-cell apoptosis predicts acute onset CIDP

Guillain-Barré syndrome (GBS) and chronic inflammatory demyelinating polyneuropathy (CIDP) are immune-mediated neuropathies. GBS is characterized by acute onset and subsequent remission of symptoms, whereas CIDP displays slow progression over at least 2 months. However, a small proportion of CIDP patients display acute onset CIDP (a-CIDP) resembling that of GBS. The Fas receptor is involved in shutting off the immune response and its defective function predisposes to auto-immune diseases. In CIDP patients, Fas function is lower than in GBS patients and healthy controls. This study is aimed at assessing whether evaluation of T-cell Fas function helps in early discrimination between GBS and a-CIDP. Fas function was evaluated in patients with acute onset polyneuropathy: 55 retrospective patients analyzed after development of GBS or a-CIDP before year 2005; 50 prospective patients analyzed at onset after year 2005 and followed up for development of GBS or a-CIDP. In both groups, a-CIDP patients displayed defective Fas function, whereas GBS patients displayed normal function. These findings suggest that the evaluation of Fas function in acute onset polyneuropathy helps in early prediction of long-term outcome.     

Reductions in muscle quality and quantity in chronic inflammatory demyelinating polyneuropathy patients assessed by magnetic resonance imaging

Introduction: Weakness in patients with chronic inflammatory demyelinating polyneuropathy (CIDP) may be caused by decreases in muscle quantity and quality, but this has not been explored. Methods: Twelve patients with CIDP (mean age 61 years) and 10 age‐matched (mean age 59 years) control subjects were assessed for ankle dorsiflexion strength, and two different MRI scans (T1 and T2) of leg musculature. Results: Isometric strength was 36% lower in CIDP patients compared with controls. Tibialis anterior muscle volumes of CIDP patients were smaller by ～17% compared with controls, and non‐contractile tissue volume was ～58% greater in CIDP patients. When normalized to total muscle or corrected contractile volume, strength was ～29% and ～18% lower, respectively, in CIDP patients. Discussion: These results provide insight into the structural integrity of muscle contractile proteins and pathologic changes to whole‐muscle tissue composition that contribute to impaired muscle function in CIDP. Muscle Nerve 58 : 396–401, 2018