Biochemical features of chronic inflammatory demyelinating polyradiculoneuropathy

Although there are no specific biological markers of chronic inflammatory demyelinating polyneuropathies (CIDP), biological investigations have played an important role in determining the limits of the concept of CIDP. This is best exemplified by the individualisation of demyelinating neuropathies associated with IgM monoclonal proteins reacting with glycolipids. The signification of CIDP associated with diabetes mellitus, monoclonal IgG or IgA, or mutations of myelin proteins has recently been discussed as they may have implications in our understanding of the pathophysiology of CIDP and raise the question of knowing whether they confer to CIDP a particular clinical presentation or evolution.     

Differential diagnosis of chronic dysimmune demyelinating polyneuropathies with and without anti-MAG antibodies

The distinction between chronic demyelinating polyneuropathies associated with IgM paraproteinemia and anti-myelin-associated glycoprotein (MAG) antibodies (MAG-PN) and chronic inflammatory demyelinating polyneuropathies (CIDPs) relies on the anti-MAG antibodies assay. The aim of the study was to identify clinical and electrophysiological features suggesting a diagnosis of MAG-PN. Fourteen patients with MAG-PN and 35 with CIDP were included, and a discriminant analysis was performed to identify the clinical and electrophysiological features suggestive of MAG-PN. Pure sensory clinical phenotype, low median and ulnar terminal latency index, and absence of M responses in the lower limbs were significantly associated with the diagnosis of MAG-PN, and indicate a moderate to large increase in probability of this diagnosis in patients with chronic dysimmune demyelinating polyneuropathies.     

Chronic polyneuropathies in Vest-Agder, Norway

Epidemiological data on chronic polyneuropathies, especially inflammatory types, is limited. The purpose of this study was to examine the spectrum of causes and estimated prevalence of various polyneuropathy types in Vest‐Agder, and to examine the clinical features of the Vest‐Agder population of chronic inflammatory demyelinating polyneuropathy (CIDP). In Vest‐Agder county (population of 155 464), polyneuropathy patients are registered in a database and followed prospectively. We did a measure of the database on October 31 1999. A total of 192 patients were registered. The prevalence for chronic inflammatory demyelinating polyneuropathy (CIDP) was 7.7 per 100 000 population. The course was relapsing in five of fifteen patients, progressive in four patients and slowly progressive in six of fifteen patients. Two of the fifteen patients had pure sensory symptoms. The mean Rankin disability score was 3.4 at maximal deficit and 2.1 at last follow‐up. The prevalence of paraproteinemic polyneuropathy was 5.1 per 100 000 population. None of the patients with paraproteinemic polyneuropathy were worse than slightly disabled (disability score ≤ 2). The prevalences for other polyneuropathies were as follows: polyneuropathy and RA, 1.3; polyneuropathy and Sjögren's syndrome or sicca complex, 4.5 (polyneuropathy was the presenting symptom in five of seven patients); sarcoidosis 1.9; polyneuropathy and chronic Lyme, 0.6; paraneoplastic polyneuropathy, 1.9; diabetic polyneuropathy 23.2; vitamin deficiency, 5.1; alcoholic and toxic polyneuropathy, 19.9; hereditary polyneuropathy, 14.8. Cryptogenic polyneuropathies made up 26% of all polyneuropathies. The mean disability score was 2.0 (SD 1.1). In conclusion, prevalence of CIDP was significantly higher than previously reported, and the prognosis was good in the majority of patients. Patients with paraproteinemic polyneuropathy were not severely disabled. Polyneuropathy was the presenting symptom in the majority of patients with Sjögren's syndrome or sicca complex.     

Chronic acquired demyelinating symmetric polyneuropathy classified by pattern of weakness

OBJECTIVES: To study a representative group of patients with chronic acquired symmetric demyelinating polyneuropathies, and to evaluate classification by pattern of weakness and by presence of immunoglobulin monoclonal protein (M protein). METHODS: In Vest-Agder County, Norway, an unselected population of patients with chronic symmetric polyneuropathies who fulfill electrodiagnostic criteria for demyelination are registered in a database and followed up prospectively. Data were taken from the database on April 2, 2001. Patients with proximal as well as distal weakness were classified as having chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), and patients with only distal symptoms as having distal acquired demyelinating symmetric polyneuropathy (DADS). RESULTS: A total of 29 patients had chronic acquired symmetric demyelinating polyneuropathy; 15 had CIDP and 14 had DADS. The 2 categories differed regarding spinal protein level (mean +/- SD, 0.102 +/- 0.060 g/dL in CIDP vs 0.065 +/- 0.029 g/dL in DADS; P =.05); clinical course (remitting in 6 of 13 patients with CIDP vs 0 of 14 with DADS; P =.02); disability score at diagnosis (mean +/- SD, 3.3 +/- 1.0 in CIDP vs 1.9 +/- 0.6 in DADS; P<.001) and at peak of symptoms (mean +/- SD, 3.6 +/- 1.1 in CIDP vs 2.3 +/- 0.6 in DADS; P<.001); and response to immunosuppressive treatment (11 of 12 patients with CIDP vs 2 of 7 with DADS; P =.01). An M protein was detected in 8 patients (3 with CIDP and 5 with DADS). Patients with polyneuropathy with and without M protein were similar in clinical features, course, disability, and treatment response. CONCLUSION: Classification by presence or absence of proximal weakness separates patients with chronic acquired symmetric demyelinating polyneuropathy into groups that are different in clinical course, disability, and treatment response.     

Immunneuropathien

The Guillain-Barré syndrome (GBS) and chronic inflammatory demyelinating polyneuropathy (CIDP) are the most common immune-mediated polyneuropathies, which can show variable clinical and electrophysiological manifestations. Rarer immune-mediated neuropathies encompass paraproteinemic neuropathies (PPN), multifocal motor neuropathy (MMN) and vasculitic neuropathies. The diagnosis usually relies on the history of symptom evolution, distribution of nerve dysfunction and particularly on characteristic features in nerve conduction studies, aided by cerebrospinal fluid (CSF) examination and nerve biopsy findings. The therapeutic toolbox encompasses corticosteroids, immunoglobulins and plasmapheresis often accompanied by long-term immunosuppression. It is important to note that immune-mediated neuropathies selectively respond to treatment and contraindications need to be considered. Despite treatment a considerable number of patients suffer from permanent neurological deficits.     

Assessing grip strength in healthy individuals and patients with immune-mediated polyneuropathies

Grip strength reference values for a portable dynamometer, the hand-held Vigorimeter, were calculated, and its validity, reliability, and responsiveness were examined in patients with immune-mediated polyneuropathies. We studied 530 healthy controls (age 5-93 years), 113 patients with stable polyneuropathy (83 with Guillain-Barré syndrome [GBS], 22 with chronic inflammatory demyelinating polyneuropathy [CIDP], and 8 with a gammopathy-associated polyneuropathy), and 20 patients with GBS or CIDP and changing clinical conditions (longitudinal group). An arm-disability scale was also assessed. Grip-strength reference values were calculated depending primarily on age and gender. Significant association was obtained between the Vigorimeter and the arm scale (in stable group, Spearman rank: r = -0.52 to -0.62; P or = 0.8) were demonstrated for the Vigorimeter. These results emphasize the clinical usefulness of the Vigorimeter, particularly in patients with immune-mediated polyneuropathies.     

Conventional and unconventional therapies in typical and atypical chronic inflammatory demyelinating polyneuropathy with different clinical course of progression

Intravenous immunoglobulin (IVIG), corticosteroids and therapeutic plasma exchange (TPE) are evidence‐based conventional treatments for chronic inflammatory demyelinating polyneuropathy (CIDP). In many centres, unconventional treatments are frequently used as alternatives. We evaluated the outcome of conventional and unconventional therapies in 31 CIDP patients. Overall response rate with conventional first‐line immunotherapies was 77% (20/26), comparable between IVIG and corticosteroids (80% vs 70%). Use of TPE was limited. Treatment response among typical and atypical CIDP were comparable (76 vs 80%). Non‐responders were patients with progressive form of typical CIDP and DADS. Majority (21/26, 81%) of patients with persistent neurological deficits received maintenance therapy. Two subgroups of patients frequently treated with maintenance immunosuppressants were those with improving or stable disease following first‐line treatment (12, 57%) and those with progressive form of CIDP (2, 10%). Primary indications for immunosuppressant use were corticosteroids‐sparing and additional immunosuppression effects. Nine (64%) patients with improving or stable disease given azathioprine were taken off corticosteroids after a median duration of 14 months (range 12‐108). Two (14%) eventually achieved cure or clinical remission without treatment. Maintenance IVIg was given to 6 (29%) relapsing CIDP patients; none of achieved cure or remission after similar median duration of treatment. Less potent immunosuppressant drugs (azathioprine, mycophenolate mofetil, and methotrexate) were frequently used, with moderate adverse effect profiles. In resource limited setting, unconventional treatments were commonly used among CIDP patients with different clinical course of progression. In most cases, careful risk‐benefit re‐assessment is required to justify its further use.     

血清抗糖脂抗体在自身免疫性多发性周围神经病中的意义

目的 :探讨抗周围神经膜表面糖脂抗体在自身免疫介导的多发性周围神经病中的临床意义。方法 :ELISA法测定格林 巴利综合征和慢性炎性脱髓鞘性周围神经病患者血清中抗硫脂抗体和 7种节苷脂抗体 (GM1、GM2、GA1、GD1a、GD1b、GT1b和GQ1b)的阳性率。结果 :GBS和CIDP组患者抗硫脂抗体、抗GM1、GA1和GD1b抗体的阳性率显著高于非自身免疫性周围神经病组 (P <0 0 5 ) ;此两组患者间的抗体阳性率比较则无显著差异 ;GBS组内有眼 /咽肌麻痹的患者 (17例 )与无眼肌和 (或 )咽喉肌麻痹患者 (2 5例 )的节苷脂抗体阳性率也无显著差异。结论 :血清抗硫脂抗体和抗GM1抗体增高对自身免疫介导的多发性周围神经病患者有一定临床意义。     

Clinimetric evaluation of a new overall disability scale in immune mediated polyneuropathies

OBJECTIVES: To determine the validity, reliability, and responsiveness of a new overall disability sum score in immune mediated polyneuropathies. METHODS: Three impairment measures (MRC sum score, sensory sum score, grip strength (Vigorimeter)) and three disability scales (an overall disability sum score (ODSS), Hughes' functional scale (f score), Rankin scale) were assessed in a cross sectional group of 113 clinically stable patients (83 with Guillain-Barré syndrome, 22 with chronic inflammatory demyelinating polyneuropathy (CIDP), eight with a gammopathy related polyneuropathy). The ODSS was also used serially in 20 patients with recently diagnosed Guillain-Barré syndrome (n = 7) or CIDP (n = 13) and changing clinical conditions. Multiple regression studies were performed to compare the impact of impairment disturbances (independent variables) on the various disability scales (dependent variable). RESULTS: Moderate to good construct validity (stable group: Spearman's rank test (absolute values), r = 0.41-0.79; longitudinal group: multiple correlation coefficient, R = 0.69-0.89; p < 0.006 for all associations) and reliability (intraclass correlation coefficient, R = 0.90-0.95; p < 0.0001) were demonstrated for the ODSS. Its SRM values were high (> 0.8), indicating good responsiveness. Impairment measures accounted for a higher variance proportion of the ODSS compared with the f score and Rankin (R = 0.64 v 0.56 and 0.45, respectively). CONCLUSIONS: All clinimetric requirements were met by the overall (arm and leg) disability sum score in immune mediated polyneuropathies. Its use is therefore suggested in evaluating immune mediated polyneuropathies.     

Polyneuropathy associated with IgG/IgA monoclonal gammopathy: a clinical and electrophysiological study of 15 cases

Peripheral neuropathy has been widely reported in patients with monoclonal gammopathy (MG), more frequently immunoglobulin M (IgM) or IgG than IgA. Nevertheless, it remains unclear whether this association has clinical or pathogenic relevance. In order to clarify the possible role of IgG/IgA MG in neuropathy, we studied the clinical and electrophysiological features of 15 consecutive patients with polyneuropathy and IgG/IgA-MG, and compared them to those of 40 patients with polyneuropathy associated with IgM-MG, previously reported. Nine middle-aged patients (60%) had a chronic progressive or relapsing demyelinating polyneuropathy (DP) that was clinically and electrophysiologically indistinguishable from classic chronic inflammatory demyelinating polyneuropathy (CIDP) and frequently responded to immunosuppressive treatments, both characteristics supporting a dysimmune process. Six older patients (40%) had a chronic axonal distal polyneuropathy similar to the so-called chronic cryptogenic sensory polyneuropathy: there was no clear relationship with the MG in these patients and the response to immunosuppressive treatments was poor. Several features allowed us to distinguish between polyneuropathies associated with IgG/IgA-MG (IgG/IgA-PN) considered together and polyneuropathies associated with IgM-MG (IgM-PN). In the first group, the proportion of patients with a predominantly sensory clinical picture (27%) was less than that in the second group (75%), and there were fewer changes in nerve conduction studies. In addition, we found that the nine patients with DP associated with IgG/IgA-MG (IgG/IgA-DP) differed from the 31 with DP associated with IgM-MG (IgM-DP): clinical and electrophysiological studies clearly showed that the demyelinating pattern was more heterogeneous in IgG/IgA-DP than in IgM-DP. The spectrum of polyneuropathies associated with IgG/IgA-MG is heterogeneous, including DP, which is similar to classic CIDP, and axonal polyneuropathy, in which the pathogenic role of the MG remains elusive. In addition, IgG/IgA-DP differ from IgM-DP on clinical and electrophysiological grounds, suggesting probable different physiopathological mechanisms.     

Chronic inflammatory demyelinating polyneuropathy presenting with features of GBS

The authors report five patients with inflammatory demyelinating polyneuropathy with a Guillain-Barré syndrome (GBS)-like onset and initial clinical features, but with persistent symptoms similar to chronic inflammatory demyelinating polyneuropathy (CIDP). Patients in the chronic phase improved with corticosteroid or IV immunoglobulin therapy. Patients with apparent GBS who show persistent symptoms may benefit from corticosteroids or other treatment that is beneficial in the management of CIDP.     

Psychometric evaluation of a new handicap scale in immune-mediated polyneuropathies

A new handicap measure, the Rotterdam nine-item handicap scale, was developed and its validity, reliability, and responsiveness evaluated in patients with immune-mediated polyneuropathies. We evaluated 113 stable patients, of whom 83 had Guillain--Barré syndrome (GBS), 22 had chronic inflammatory demyelinating polyneuropathy (CIDP), and 8 had a gammopathy-related polyneuropathy. We also studied 20 patients with recently diagnosed GBS (n = 7) or CIDP (n = 13) and changing clinical conditions (longitudinal group). Significant discriminatory validity and correlation with the Rankin scale were demonstrated for the Rotterdam nine-item handicap scale (stable group: Spearman's test, r = minus sign.76 to minus sign.78; longitudinal group: intraclass correlation coefficient, r =.83; P <.0001). Also, good reliability (r =.89--.98; P <.0001) and high responsiveness values (standardized response mean values >.8) were obtained for the Rotterdam nine-item handicap scale. In contrast to the Rankin scale, the Rotterdam scale not only provided information regarding mobility but also highlighted physical independence, occupation, and social integration. These results illustrate the clinical usefulness of the Rotterdam nine-item handicap scale under these conditions.     

Peripheral neuropathy associated with monoclonal IgG of undetermined significance: clinical, electrophysiologic, pathologic and therapeutic study of 14 cases

Fourteen patients with peripheral neuropathy and monoclonal IgG of undetermined significance are reported with a retrospective study of the clinical features, electrophysiologic and sural nerve biopsy findings. There were two groups. Five patients had a relapsing chronic sensorimotor polyneuropathy with clinical (5/5), electrophysiologic (4/5) and pathologic (5/5) features compatible with chronic inflammatory demyelinating polyneuropathies (CIDP). The nine others had a slowly progressive sensory (5/9) (SPNP) or sensorimotor (4/9) (SMPNP) axonal polyneuropathy. Four patients of the first group were treated with intravenous human immunoglobulin (400 mg/kg/day for five days) with significant clinical improvement. The motor conduction velocities and distal latencies of two of these patients improved following treatment, thus matching the clinical improvement. Our results on peripheral nerve biopsies confirm the differentiation of patients with CIDP from those with SMPNP and SPNP. There was no specific immunologic serologic reactivity in any of the cases.     

Motor chronic inflammatory demyelinating polyneuropathy (CIDP) in 17 patients: Clinical characteristics,electrophysiological study,and response to treatment

Motor chronic inflammatory demyelinating polyneuropathy (CIDP) is a rare and poorly described subtype of CIDP. We aimed to study their clinical and electrophysiological characteristics and response to treatment. From a prospective database of CIDP patients, we included patients with definite or probable CIDP with motor signs and without sensory signs/symptoms at diagnosis. Patients were considered to have pure motor CIDP (PM‐CIDP) if sensory conductions were normal or to have motor predominant CIDP (MPred‐CIDP) if ≥2 sensory nerve action potential amplitudes were abnormal. Among the 700 patients with CIDP, 17 (2%) were included (PM‐CIDP n = 7, MPred‐CIDP n = 10); 71% were male, median age at onset was 48 years (range: 13‐76 years), 47% had an associated inflammatory or infectious disease or neoplasia. At the more severe disease stage, 94% of patients had upper and lower limb weakness, with distal and proximal weakness in 4 limbs for 56% of them. Three‐quarters (75%) responded to intravenous immunoglobulins (IVIg) and four of five patients to corticosteroids including three of three patients with MPred‐CIDP. The most frequent conduction abnormalities were conduction blocks (CB, 82%) and F‐wave abnormalities (88%). During follow up, 4 of 10 MPred‐CIDP patients developed mild sensory symptoms; none with PM‐CIDP did so. Patients with PM‐CIDP had poorer outcome (median ONLS: 4; range: 22‐5) compared to MPred‐CIDP (2, range: 0‐4; P = .03) at last follow up. This study found a progressive clinical course in the majority of patients with motor CIDP as well as frequent associated diseases, CB, and F‐wave abnormalities. Corticosteroids might be considered as a therapeutic option in resistant IVIg patients with MPred‐CIDP.     

Chronic inflammatory demyelinating polyneuropathy: a 6-year retrospective clinical study of a hospital-based population.

We reviewed the clinical, electrophysiological, laboratory and neuroimaging features of 25 patients with chronic inflammatory demyelinating polyneuropathy (CIDP) admitted to Aeginition Hospital from 1996 to 2001. We also investigated the response to several treatment modalities. The aim was to reveal the clinical spectrum of the disease; the diagnostic criteria developed by the Ad Hoc Subcommittee of the American Academy of Neurology (AAN) in 1991 were used. The subjects consisted of 17 men (68%) and eight women (32%) aged 18-81 years (mean age: 48.5 years) with CIDP. Eighteen patients (72%) had a symmetric neuropathy, whereas seven (28%) had an asymmetric neuropathy. Two patients (8%) had a pure sensory neuropathy. Nine (36%) presented with cranial nerve involvement and only one (4%) had central nervous system demyelination. Most patients had a satisfactory response after treatment with corticosteroids, intravenous immunoglobulins, plasma exchange and azathioprine. In conclusion, CIDP is a clinically heterogeneous disorder. It is one of the few serious chronic neuropathies that has a good (although not permanent) treatment response.     

Chronic inflammatory demyelinating polyneuropathy--update on pathogenesis, diagnostic criteria and therapy

PURPOSE OF REVIEW: Chronic inflammatory demyelinating polyneuropathy (CIDP) is a treatable but possibly underdiagnosed disorder of the peripheral nerve. This review covers the growing literature of the past years that deals with the pathogenesis, diagnostic criteria and treatment of CIDP. RECENT FINDINGS: The recent development of a biphasic animal model of experimental autoimmune neuritis may provide further insights into the pathogenesis of inflammatory demyelination of the peripheral nerve, such as in CIDP, and may allow the development of further innovative therapeutic strategies. In patients, the contribution of immune processes to the dysfunction in hereditary polyneuropathies and the association of hereditary neuropathy and CIDP has been described. Commonly used therapies remain corticosteroids, intravenous immunoglobulin and plasmapheresis; however, newer immunosuppressant approaches using mycophenolate mofetil or cyclosporin A, or immunomodulating therapies using monoclonal antibodies or interferons are presently under investigation. SUMMARY: The growing body of knowledge on the pathogenesis of CIDP and further diagnostic differentiation of subforms may help to develop more-effective therapies for CIDP in the next few years.     

Clinical spectrum of chronic acquired demyelinating polyneuropathies

A number of presentations of chronic demyelinating polyneuropathy have been identified, each distinguished by its phenotypic pattern. In addition to classic chronic inflammatory demyelinating polyneuropathy (CIDP), which is characterized clinically by symmetric proximal and distal weakness and sensory loss, several regional variants can be recognized: multifocal motor neuropathy (MMN: asymmetric and pure motor), multifocal acquired demyelinating sensory and motor (MADSAM) neuropathy (asymmetric, sensory, and motor), and distal acquired demyelinating symmetric (DADS) neuropathy (symmetric, distal, sensory, and motor). There are also temporal, pathological, and disease-associated variants. This review describes a clinical scheme for approaching the chronic acquired demyelinating polyneuropathies that leads to a rational use of supportive laboratory studies and treatment options. In addition, we propose new diagnostic criteria for CIDP that more accurately reflect current clinical practice.     

Myasthenia gravis and chronic inflammatory demyelinating polyneuropathy

We describe a patient with the previously unreported association of chronic inflammatory demyelinating polyneuropathy (CIDP) and myasthenia gravis (MG). Immunosuppressive treatment with azathioprine and prednisone achieved clinical and electrophysiological remission of MG and improvement of CIDP. As ophthalmoplegia occurs infrequently in CIDP, the possibility of MG should be considered when this sign is present in a patient with CIDP. Since current therapy with corticosteroids, plasma exchange and other immunomodulating agents is effective against both diseases, their association may be undereported.     

<Emphasis Type="Italic">N</Emphasis><Superscript>ε</Superscript>-Carboxymethyllysine in diabetic and non-diabetic polyneuropathies

Increased oxidative stress and advanced glycosylation are important factors in the development of diabetic neuropathy. In non-diabetic neuropathies their influence has not been investigated in detail so far. We studied the localisation of N(epsilon)-carboxymethyllysine (CML) - a biomarker for oxidative stress - by immunohistochemistry in sural nerve biopsies of 31 patients with different polyneuropathies [diabetic polyneuropathy (n=5), alcohol-associated polyneuropathy (n=4), vitamin B12-deficient polyneuropathy (n=6), chronic inflammatory demyelinating polyneuropathy (CIDP) (n=6), vasculitic neuropathy (n=6), Charcot-Marie-Tooth disease type I (CMT I) (n=4)] and 4 normal controls. CML was detected in the perineurium of patients with diabetic, alcohol-associated, vitamin B12-deficient and vasculitic polyneuropathies. Epineurial, perineurial and endoneurial vessels were CML positive in diabetic, vitamin B12-deficient and vasculitic polyneuropathies. CML was also found in mononuclear inflammatory cells in vasculitic neuropathy. In CIDP and normal controls there was only marginal perineurial CML deposition in 2/6 and 1/4 cases. In CMT I no CML was detected. Immunohistochemical results were confirmed by immunoblot. Our data suggest a role of oxidative stress in the pathogenesis not only of diabetic but also of alcohol-associated, vitamin B12-deficient and vasculitic polyneuropathies. It may be a minor pathogenetic factor in CIDP and may not be involved in CMT I. Underlying causes for increased oxidative stress may be an elevated production of reactive oxygen species and an impairment of antioxidative defences. Therefore, an antioxidative treatment should be considered in alcohol-associated, vitamin B12-deficient and vasculitic polyneuropathy.     

Fampridine‐PR (prolonged released 4‐aminopyridine) is not effective in patients with inflammatory demyelination of the peripheral nervous system

Fampridine‐PR is a voltage‐gated potassium channel inhibitor potentially improving nerve conduction in demyelinated axons. Based on its established clinical efficacy in patients with demyelination in the central nervous system, we assessed if fampridine‐PR is also effective in patients with inflammatory demyelination of the peripheral nerve. In this small open‐label study, 10 patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) were treated with fampridine‐PR 10 mg BID for 28 days and assessed clinically as well as by nerve conduction studies. In this study, Fampridine‐PR failed to improve CIDP based on clinical measures and nerve conduction studies. Our findings suggest that Fampridine‐PR appears to be ineffective in demyelinating polyneuropathies. These observations may indicate a more complex mode of action beyond improving action potential conduction in demyelinated axons.