Robert D.M. Hadden

European federation of neurological societies/peripheral nerve society guideline on management of chronic inflammatory demyelinating polyradiculoneuropathy: Report of a joint task force of the European Federation of Neurological Societies and the Peripheral Nerve Society - First Revision

Background:  Consensus guidelines on the definition, investigation, and treatment of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) have been previously published in European Journal of Neurology and Journal of the Peripheral Nervous System.

Pathogenesis of Guillain-Barré syndrome.

Recent neurophysiological and pathological studies have led to a reclassification of the diseases that underlie Guillain-Barré syndrome (GBS) into acute inflammatory demyelinating polyradiculoneuropathy (AIDP), acute motor and sensory axonal neuropathy (AMSAN) and acute motor axonal neuropathy (AMAN). The Fisher syndrome of ophthalmoplegia, ataxia and areflexia is the most striking of several related conditions. Significant antecedent events include Campylobacter jejuni (4-66%), cytomegalovirus (5-15%), Epstein-Barr virus (2-10%), and Mycoplasma pneumoniae (1-5%) infections. These infections are not uniquely associated with any clinical subtype but severe axonal degeneration is more common following C. jejuni and severe sensory impairment following cytomegalovirus. Strong evidence supports an important role for antibodies to gangliosides in pathogenesis. In particular antibodies to ganglioside GM1 are present in 14-50% of patients with GBS, and are more common in cases with severe axonal degeneration associated with any subtype. Antibodies to ganglioside GQ1b are very closely associated with Fisher syndrome, its formes frustes and related syndromes. Ganglioside-like epitopes exist in the bacterial wall of C. jejuni. Infection by this and other organisms triggers an antibody response in patients with GBS but not in those with uncomplicated enteritis. The development of GBS is likely to be a consequence of special properties of the infecting organism, since some strains such as Penner 0:19 and 0:41 are particularly associated with GBS but not with enteritis. It is also likely to be a consequence of the immunogenetic background of the patient since few patients develop GBS after infection even with one of these strains. Attempts to match the subtypes of GBS to the fine specificity of anti-ganglioside antibodies and to functional effects in experimental models continue but have not yet fully explained the pathogenesis. T cells are also involved in the pathogenesis of most or perhaps all forms of GBS. T cell responses to any of three myelin proteins, P2, PO and PMP22, are sufficient to induce experimental autoimmune neuritis. Activated T cells are present in the circulation in the acute stage, up-regulate matrix metalloproteinases, cross the blood-nerve barrier and encounter their cognate antigens. Identification of the specificity of these T cell responses is still at a preliminary stage. The invasion of intact myelin sheaths by activated macrophages is difficult to explain according to a purely T cell mediated mechanism. The different patterns of GBS are probably due to the diverse interplay between antibodies and T cells of differing specificities.

European Federation of Neurological Societies/Peripheral Nerve Society Guideline on management of multifocal motor neuropathy. Report of a Joint Task Force of the European Federation of Neurological Societies and the Peripheral Nerve Society - first revision

A European Federation of Neurological Societies/Peripheral Nerve Society consensus guideline on the definition, investigation, and treatment of multifocal motor neuropathy (MMN) was published in 2006. The aim is to revise this guideline. Disease experts considered references retrieved from MEDLINE and Cochrane Systematic Reviews published between August 2004 and July 2009 and prepared statements that were agreed to in an iterative fashion. The Task Force agreed on Good Practice Points to define clinical and electrophysiological diagnostic criteria for MMN, investigations to be considered, and principal recommendations for treatment.

European Federation of Neurological Societies/Peripheral Nerve Society Guideline on management of chronic inflammatory demyelinating polyradiculoneuropathy: Report of a joint task force of the European Federation of Neurological Societies and the Peripheral Nerve Society - First Revision

Background: Consensus guidelines on the definition, investigation, and treatment of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) have been published (J Peripher Nerv Syst 2005; 10: 220–228, Eur J Neurol 2006; 13: 326–332). Objectives: To revise these guidelines. Methods: Disease experts, including a representative of patients, considered references retrieved from MEDLINE and Cochrane Systematic Reviews published between August 2004 and July 2009 and prepared statements that were agreed in an iterative fashion.

European Federation of Neurological Societies/Peripheral Nerve Society guideline on management of chronic inflammatory demyelinating polyradiculoneuropathy: report of a joint task force of the European Federation of Neurological Societies and the Peripheral Nerve Society

Numerous sets of diagnostic criteria have sought to define chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and randomized trials and systematic reviews of treatment have been published. The objective is to prepare consensus guidelines on the definition, investigation and treatment of CIDP. Disease experts and a patient representative considered references retrieved from MEDLINE and Cochrane Systematic Reviews in May 2004 and prepared statements which were agreed in an iterative fashion. The Task Force agreed on good practice points to define clinical and electrophysiological diagnostic criteria for CIDP with or without concomitant diseases and investigations to be considered. The principal treatment recommendations were: (1) intravenous immunoglobulin (IVIg) or corticosteroids should be considered in sensory and motor CIDP (level B recommendation); (2) IVIg should be considered as the initial treatment in pure motor CIDP (Good Practice Point); (3) if IVIg and corticosteroids are ineffective plasma exchange (PE) should be considered (level A recommendation); (4) If the response is inadequate or the maintenance doses of the initial treatment are high, combination treatments or adding an immunosuppressant or immunomodulatory drug should be considered (Good Practice Point); (5) Symptomatic treatment and multidisciplinary management should be considered (Good Practice Point).

European Federation of Neurological Societies/Peripheral Nerve Society Guideline* on management of chronic inflammatory demyelinating polyradiculoneuropathy. Report of a joint task force of the European Federation of Neurological Societies and the Peripheral Nerve Society

Abstract  Background: Numerous sets of diagnostic criteria have sought to define chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), and randomized trials and systematic reviews of treatment have been published. Objectives: The aim of this guideline was to prepare consensus guidelines on the definition, investigation, and treatment of CIDP. Methods: Disease experts and a representative of patients considered references retrieved from MEDLINE and Cochrane Systematic Reviews in May 2004 and prepared statements that were agreed in an iterative fashion. Recommendations: The Task Force agreed on good practice points to define clinical and electrophysiological diagnostic criteria for CIDP with or without concomitant diseases and investigations to be considered. The principal treatment recommendations were as follows: (1) intravenous immunoglobulin (IVIg) or corticosteroids should be considered in sensory and motor CIDP (level B recommendation); (2) IVIg should be considered as the initial treatment in pure motor CIDP (good practice point); (3) if IVIg and corticosteroids are ineffective, plasma exchange should be considered (level A recommendation); (4) if the response is inadequate or the maintenance doses of the initial treatment are high, combination treatments or adding an immunosuppressant or immunomodulatory drug should be considered (good practice point); and (5) symptomatic treatment and multidisciplinary management should be considered (good practice point).

Peripheral Nerve Society Guideline† on the classification, diagnosis, investigation, and immunosuppressive therapy of non-systemic vasculitic neuropathy: executive summary

Non‐systemic vasculitic neuropathy (NSVN) is routinely considered in the differential diagnosis of progressive axonal neuropathies, especially those with asymmetric or multifocal features. Diagnostic criteria for vasculitic neuropathy, classification criteria for NSVN, and therapeutic approaches to NSVN are not standardized. The aim of this guideline was to derive recommendations on the classification, diagnosis, investigation, and treatment of NSVN based on the available evidence and, where evidence was not available, expert consensus. Experts on vasculitis, vasculitic neuropathy, and methodology systematically reviewed the literature for articles addressing diagnostic issues concerning vasculitic neuropathy and NSVN as well as treatment of NSVN and the small‐to‐medium vessel primary systemic vasculitides using MEDLINE, EMBASE, and the Cochrane Library. The selected articles were analyzed and classified. The group initially reached consensus on a classification of vasculitides associated with neuropathy. Non‐diabetic radiculoplexus neuropathy was incorporated within NSVN. The consensus definition of pathologically definite vasculitic neuropathy required that vessel wall inflammation be accompanied by vascular damage. Diagnostic criteria for pathologically probable vasculitic neuropathy included five predictors of definite vasculitic neuropathy: vascular deposits of IgM, C3, or fibrinogen by direct immunofluorescence; hemosiderin deposits; asymmetric nerve fiber loss; prominent active axonal degeneration; and myofiber necrosis, regeneration, or infarcts in peroneus brevis muscle biopsy (Good Practice Points from class II/III evidence). A case definition of clinically probable vasculitic neuropathy in patients lacking biopsy proof incorporated clinical features typical of vasculitic neuropathy: sensory or sensory‐motor involvement, asymmetric/multifocal pattern, lower‐limb predominance, distal‐predominance, pain, acute relapsing course, and non‐demyelinating electrodiagnostic features (Good Practice Points from class II/III evidence). Proposed exclusionary criteria for NSVN – favoring the alternate diagnosis of systemic vasculitic neuropathy – were clinicopathologic evidence of other‐organ involvement; anti‐neutrophil cytoplasmic antibody (ANCAs); cryoglobulins; sedimentation rate ≥100 mm/h; and medical condition/drug predisposing to systemic vasculitis (Good Practice Points supported by class III evidence). Three class III studies on treatment of NSVN were identified, which were insufficient to permit a level C recommendation. Therefore, the group reviewed the literature on treatment of primary small‐to‐medium vessel systemic vasculitides prior to deriving Good Practice Points on treatment of NSVN. Principal treatment recommendations were: (1) corticosteroid (CS) monotherapy for at least 6 months is considered first‐line; (2) combination therapy should be used for rapidly progressive NSVN and patients who progress on CS monotherapy; (3) immunosuppressive options include cyclophosphamide, azathioprine, and methotrexate; (4) cyclophosphamide is indicated for severe neuropathies, generally administered in IV pulses to reduce cumulative dose and side effects; (5) in patients achieving clinical remission with combination therapy, maintenance therapy should be continued for 18–24 months with azathioprine or methotrexate; and (6) clinical trials to address all aspects of treatment are needed.

Humoral and cellular immune responses to myelin protein peptides in chronic inflammatory demyelinating polyradiculoneuropathy

Objectives: Evidence that chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an autoimmune disease was sought, by studying cellular and humoral immune responses to peripheral nerve myelin proteins. Methods: 40 CIDP, 36 healthy control subjects (HC) and subjects with non-immune mediated neuropathies (other neuropathies, ON) for antibodies were studied by ELISA and cellular responses by cytokine ELISPOT (INFγ, IL10) and ELISA (IL17) to synthetic peptides representing P0, P2 and PMP22. Results: Antibodies to P0, P2 or PMP22 peptides were detected in only a minority of CIDP, both not treated (nT-CIDP) and treated (T-CIDP). IgG antibodies to P280–105 were significantly more frequent in CIDP than in HC (4/30 vs 0/32; p<0.05) but the difference from ON (1/25) was not significant. In ELISPOT assays, IFNγ was detected at a low frequency in CIDP and did not differ from HC or ON. In contrast, IL10 responses against P21–85 were more frequent in nT and T-CIDP (7/24 and 3/16) than HC (0/36; p<0.001 and p<0.05, respectively). The production of IL17 in cell-culture supernatants was not increased. Conclusions: Antibodies to non-conformational antigenic epitopes of myelin proteins rarely occur in CIDP. None of the myelin protein peptides elicited IFNγ responses, but P2 elicited IL10 responses significantly more often in CIDP patients than in controls. This reactivity may be part of an antigen-specific Th2 type pathogenetic or regulatory mechanism or represent a transitory epiphenomenon due to nerve damage. In our study, P2 was the protein antigen most likely to be involved in the aberrant immune responses in CIDP.

Randomized controlled trial of brain‐derived neurotrophic factor in Guillain–Barré syndrome: a pilot study

Brain‐derived neurotrophic factor (BDNF) has the theoretical potential to protect neurones from axonal degeneration. The objective of this study was to discover whether brain‐derived neurotrophic factor is safe in Guillain–Barré syndrome, and to make preliminary observations of its efficacy. This was a parallel group randomized controlled trial of subcutaneous brain‐derived neurotrophic factor 25 µg/kg daily compared with placebo for up to 24 weeks or until patients could walk without aid.

Effects on axonal conduction of anti-ganglioside sera and sera from patients with Guillain-Barré syndrome

The efficacy of plasma exchange as a therapy for Guillain-Barré syndrome (GBS) suggests that humoral factors might contribute to the axonal conduction block responsible for the major symptoms of the disease. To explore this possibility, we have applied sera to rat spinal roots in vitro while monitoring axonal conduction. Neither fresh sera from 12 patients with GBS or Miller-Fisher syndrome (MFS), nor serum from rabbits immunised with Campylobacter jejuni from patients with GBS, MFS or gastroenteritis were effective in causing acute conduction block, despite the presence of antibodies to gangliosides GD3, GM1, GQ1b and GT1a. Potential explanations are advanced.