Treating chronic relapsing Guillain-Barré syndrome by plasma exchange

Plasma exchange for chronic inflammatory demyelinating polyradiculoneuropathy

BACKGROUND

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an uncommon progressive or relapsing paralysing disease caused by inflammation of the peripheral nerves. If the hypothesis that it is due to autoimmunity is correct, removal of autoantibodies in the blood by plasma exchange should be beneficial.

OBJECTIVES

To assess the effects of plasma exchange for treating CIDP.

SEARCH METHODS

On 30 June 2015, we searched the Cochrane Neuromuscular Disease Group Specialized Register, the Cochrane Central Register for Controlled Trials (CENTRAL), MEDLINE, EMBASE, CINAHL Plus, and LILACS. We also scrutinised the bibliographies of the trials, contacted the trial authors and other disease experts, and searched trials registries for ongoing studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) or quasi-RCTs in participants of any age comparing plasma exchange with sham treatment or no treatment.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected the trials, extracted the data, and assessed risk of bias. Where possible the review authors combined data according to the methods of the Cochrane Neuromuscular Disease Review Group.

MAIN RESULTS

PRIMARY OUTCOME MEASURE

one cross-over trial including 18 participants showed after four weeks, 2 (95% confidence interval (CI) 0.8 to 3.0) points more improvement on an 11-point disability scale with plasma exchange (10 exchanges over four weeks) than with sham exchange. Rapid deterioration after plasma exchange occurred in eight of 12 who had improved.

SECONDARY OUTCOME MEASURES

when we combined the results of this cross-over trial and a trial with 29 participants treated in a parallel-group design, there were 31 points (95% CI 16 to 45) more improvement on an impairment scale (maximum score 280) after plasma exchange (six exchanges over three weeks) than after sham exchange. There were significant improvements in both trials in an electrophysiological measure, the proximally evoked compound muscle action potential, after three or four weeks. Nonrandomised evidence indicates that plasma exchange induces adverse events in 3% to 17% of procedures. These events are sometimes serious. Both trials had a low risk of bias. A trial that showed no significant difference in the benefit between plasma exchange and intravenous immunoglobulin is included in the Cochrane review of intravenous immunoglobulin for this condition.

AUTHORS' CONCLUSIONS

Moderate- to high-quality evidence from two small trials shows that plasma exchange provides significant short-term improvement in disability, clinical impairment, and motor nerve conduction velocity in CIDP but rapid deterioration may occur afterwards. Adverse events related to difficulty with venous access, use of citrate, and haemodynamic changes are not uncommon. We need more research to identify agents that will prolong the beneficial action of plasma exchange.

Plasma exchange for chronic inflammatory demyelinating polyradiculoneuropathy

BACKGROUND

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an uncommon progressive or relapsing paralysing disease caused by inflammation of the peripheral nerves. If the hypothesis that it is due to autoimmunity is correct, removal of autoantibodies in the blood by plasma exchange should be beneficial.

OBJECTIVES

To evaluate the efficacy of plasma exchange in CIDP.

SEARCH METHODS

We searched the Cochrane Neuromuscular Disease Group Specialized Register (14 May 2012), CENTRAL (2012, Issue 4), MEDLINE (January 1966 to May 2012), EMBASE (January 1980 to May 2012), CINAHL Plus (January 1937 to May 2012) and LILACS (January 1982 to May 2012). We also scrutinised the bibliographies of the trials, and contacted the trial authors and other disease experts.

SELECTION CRITERIA

Randomised controlled trials (RCTs) or quasi-RCTs in participants of any age comparing plasma exchange with sham treatment or no treatment.

DATA COLLECTION AND ANALYSIS

Two authors selected the trials, extracted the data and assessed risk of bias independently. Where possible data were combined according to the methods of the Cochrane Neuromuscular Disease Review Group.

PRIMARY OUTCOME MEASURE

one cross-over trial including 18 participants showed two (95% confidence interval (CI) 0.8 to 3.0) points more improvement after four weeks on an 11-point disability scale with plasma exchange (10 exchanges over four weeks) than with sham exchange. Rapid deterioration after plasma exchange occurred in eight of 12 who had improved.

SECONDARY OUTCOME MEASURES

when the results of this trial and another with 29 participants treated in a parallel group design trial were combined, there were 31 points (95% CI 16 to 45, maximum score 280) more improvement in an impairment scale after plasma exchange (six exchanges over three weeks) than after sham exchange. There were significant improvements in both trials in an electrophysiological measure, the proximally evoked compound muscle action potential, after three or four weeks. Non-randomised evidence indicates that plasma exchange induces adverse events in 3% to 17% of procedures. These are sometimes serious. A trial showing no significant difference in the benefit between plasma exchange and intravenous immunoglobulin has been included in the Cochrane review of intravenous immunoglobulin for this condition.

AUTHORS' CONCLUSIONS

Moderate to high quality evidence from two small trials showed that plasma exchange provides significant short-term improvement in disability, clinical impairment and motor nerve conduction velocity in CIDP but rapid deterioration may occur afterwards. Adverse events related to difficulty with venous access, use of citrate and haemodynamic changes are not uncommon. More research is needed to identify agents which will prolong the beneficial action of plasma exchange.

Plasmapheresis for chronic inflammatory demyelinating polyradiculoneuropathy

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an immune-mediated disorder characterized by progressive or relapsing symmetrical motor or sensory symptoms and signs in more than one limb, developing over at least 2 months. It may cause prolonged periods of disability and even death. Evidence from trials suggests that plasma exchange provides significant short-term benefit in about two thirds of patients with chronic inflammatory demyelinating polyradiculoneuropathy. This review evaluates the role of plasmapheresis in CIDP.

Plasma exchange for chronic inflammatory demyelinating polyradiculoneuropathy

BACKGROUND

Chronic inflammatory demyelinating polyradiculoneuropathy is an uncommon progressive or relapsing paralysing disease caused by inflammation of the peripheral nerves. If the hypothesis that it is due to autoimmunity is correct, removal of autoantibodies in the blood by plasma exchange should be beneficial.

OBJECTIVES

To evaluate the efficacy of plasma exchange in chronic inflammatory demyelinating polyradiculoneuropathy.

SEARCH STRATEGY

We searched the Neuromuscular Disease Group Register (December 2003), and MEDLINE (January 1966 to January 2003), EMBASE (January 1980 to January 2003), CINAHL (January 1982 to December 2002) and LILACS (January 1982 to January 2003). We also scrutinised the bibliographies of the trials, and contacted the trial authors and other disease experts.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials in participants of any age comparing plasma exchange with sham treatment or no treatment. A trial showing no significant difference in the benefit from plasma exchange with intravenous immunoglobulin has been included in a separate Cochrane review.

DATA COLLECTION AND ANALYSIS

Two authors selected the trials, extracted the data and assessed methodological quality independently. Where possible data were combined according to the methods of the Cochrane Neuromuscular Disease Review Group.

PRIMARY OUTCOME MEASURE

one crossover trial including 18 participants showed 2 (95% confidence interval (CI) 0.8 to 3.0) points more improvement after four weeks in an 11-point disability scale with plasma exchange (10 exchanges over four weeks) than with sham exchange. Rapid deterioration after plasma exchange occurred in eight of 12 who had improved.

SECONDARY OUTCOME MEASURES

when the results of this trial and another with 29 participants treated in a parallel group design trial were combined, there were 31 points (95% CI 16 to 45) more improvement in an impairment scale after plasma exchange (six exchanges over three weeks) than after sham exchange. There were significant improvements in both trials in an electrophysiological measure, the proximally evoked compound muscle action potential, after three or four weeks. Non-randomised evidence indicates that plasma exchange induces adverse events in 3% to 17% of procedures. These are sometimes serious.

REVIEWERS' CONCLUSIONS

Evidence from two small trials showed that plasma exchange provides significant short-term benefit in about two-thirds of patients with chronic inflammatory demyelinating polyradiculoneuropathy but rapid deterioration may occur afterwards. Adverse events related to difficulty with venous access, use of citrate and haemodynamic changes are not uncommon. More research is needed to identify agents which will prolong the beneficial action of plasma exchange.

Therapeutic plasma exchange: an update from the Canadian Apheresis Group

In 1997, the Canadian Apheresis Group reviewed data on 103,416 plasma exchange procedures that had been collected since 1980. Although the number of plasma exchanges gradually increased (from 3189 to 8208 per year), the pattern changed. In 1981, the five most frequent indications for plasma exchange resulted in 55% of all such procedures; by 1997, the five most frequent indications for plasma exchange resulted in 81.1% of all such procedures. During this period, three conditions that were originally among the most frequent indications for plasma exchange became among the least frequent. This paper reviews the published evidence that supports or refutes the use of plasma exchange in the category of the five most frequent indications from 1981 to 1997: thrombotic thrombocytopenic purpura, myasthenia gravis, chronic inflammatory demyelinating polyneuropathy, Waldenstrom macroglobulinemia, the Guillain-Barre syndrome, rheumatoid arthritis, systemic lupus erythematosus, and multiple sclerosis. For most disorders, use of plasma exchange procedures is correlated with published evidence, and the changing patterns of plasma exchange use by members of the Canadian Apheresis Group reflect published evidence. Annual center-by-center reviews of use of plasma exchange may also have influenced practice patterns.

Treatment of chronic inflammatory demyelinating polyneuropathy

The management of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is the main topic of this review. A few comments will also be made about treatment of the demyelinating form of paraproteinaemic demyelinating polyneuropathy (PDN) and of multifocal motor neuropathy (MMN). The review briefly describes the main characteristics of these neuropathies, and examines case series and trials which evaluated the principal therapeutic strategies for CIDP, PDN and MMN, such as intravenous immunoglobulin (IVIg) therapy, steroid treatment, plasma exchange and immunosuppressor administration. Controlled trials demonstrated that IVIg, steroid treatment and plasma exchange are effective in CIDP. For PDN the therapeutic strategies are the same as for idiopathic CIDP, but usually the clinical response is poorer. For MMN, IVIg therapy is definitely the first choice treatment.

Chronic immune-related demyelinating neuropathies

In recent years many important advances have been made in the knowledge of the mechanisms that may produce peripheral nerve damage. Data in the literature indicate that in some chronic demyelinating neuropathy autoantibodies against myelin antigens may play a pathogenic role. The pathogenic role of T cells, cytokines, complement, and class II molecules has also been studied. Identification of specific immune-related demyelinating polyneuropathies provides clues to future therapeutic approaches. This paper focuses on the chronic inflammatory demyelinating polyneuropathy, chronic demyelinating neuropathies associated with monoclonal gammapathies of undetermined significance, and multifocal motor neuropathy, and reviews their clinical, patophysiological and immunological features.

Cerebrospinal fluid pheresis in Guillain Barré syndrome

While plasmapheresis is established in the treatment of acute polyneuroradiculitis, disabling pareses may last long, persisting neurological deficits remain frequent, and costs and side-effects are considerable. Repeated filtration of cerebrospinal fluid may remove pathogenetically relevant cells and polypeptides. Observations in 12 severe Guillain-Barré patients treated with CSF pheresis indicate that it is a safe and effective procedure. We hypothesize mechanisms of action of and potential indications for CSF pheresis as a more general concept. In inflammatory demyelinating polyneuropathy, CSF filtration could be combined with 'dynamic' cerebrospinal fluid pheresis, intravenous immunoglobulin therapy, cryoprecipitation, and/or immuno-adsorption to increase its effectiveness.

Liquorpheresis (CSF-filtration): an effective treatment in acute and chronic severe autoimmune polyradiculoneuritis (Guillain-Barré syndrome)

In recent years, plasmapheresis has become a well established treatment of acute and chronic polyradiculoneuritis (Guillain-Barré syndrome, GBS). Nevertheless, there are still non-responders and there are particular risks associated with this treatment. Despite all efforts, the duration of severe forms of Guillain-Barré syndrome is still considerable. Inflammation and demyelination start intrathecally. We therefore used liquorpheresis (cerebrospinal fluid filtration) as a new effective therapeutic approach. Our first patient, severely disabled with acute GBS, artificially ventilated, had undergone plasma exchange without effect. Plasma immunoadsorption led only to transient improvement. After several liquorphereses, the patient recovered completely. In three additional patients with acute and two with chronic GBS an improvement of clinical signs in close temporal relation to liquorpheresis was observed. Twice, liquorpheresis was combined with immunoadsorption of cerebrospinal fluid. Liquorpheresis was well tolerated in all cases. This procedure may be effective by eliminating humoral or cell-bound factors responsible for the onset or/and maintenance of inflammation. Further controlled studies are necessary and are in progress.

Acquired inflammatory demyelinating polyneuropathies: clinical and electrodiagnostic features

The acquired demyelinating polyneuropathies include acute (AIDP, Guillain-Barré syndrome, GBS) and chronic (CIDP, dysproteinemic) forms which differ primarily in their temporal profile. They are inflammatory-demyelinating diseases of the peripheral nervous system and likely have an immunologic pathogenesis. Although these neuropathies usually have a characteristic presentation, the electromyographer plays a central role in their recognition, since the demyelinating component of the neuropathy, which greatly reduces the differential diagnosis, is often first identified in the electromyography laboratory. In AIDP, the electromyographer, in addition to establishing the diagnosis, can sometimes predict the prognosis. Recognition of the chronic and dysproteinemic forms of acquired demyelinating polyneuropathy is important since they are treatable. The dysproteinemic forms also may be associated with occult systemic disorders that also may require treatment, independent of the neuropathy.

Chronic recurrent Guillain-Barré syndrome: report of 3 cases

The classical Guillain-Barré syndrome is an acute or subacute polyradiculo-neuropathy whose main clinical features are progressive weakness of the limbs, decrease or absence of tendon reflexes, and sensory changes. Although in most of the cases there is complete recovery in weeks or months, some patients have a slow and progressive relapsing course and present thickening of the peripheral nerves. In this paper we describe three cases of the chronic and relapsing variety of Guillain-Barré syndrome, two of which had prominent hypertrophic changes in the peripheral nerves with onion bulb formations. The clinical and pathological features of this disease are reviewed. The three patients improved with the use of steroids.

A critical review of therapies in acute and chronic inflammatory demyelinating polyneuropathies

Acute and chronic inflammatory demyelinating neuropathies are among the most common treatable neuropathies seen by neurologists. Evidence for effective therapy has only recently been provided by randomized or controlled trials. In the Guillain-Barré syndrome such evidence does not support the use of corticosteroids or immunosuppressive agents. However, when used early in the course, plasma exchange (PE) has been shown to lessen the severity and shorten the duration of the disease; it is indicated only in severely paralyzed patients or those whose rapid deterioration suggests the imminent need for ventilatory support. Some patients with chronic inflammatory demyelinating polyneuropathy (CIDP) respond to corticosteroid therapy or other immunosuppressive agents. PE is also effective in certain patients, but there is no sound evidence to date concerning combined immunosuppression and PE. The rationale of PE in these conditions and whether it is the removal of a toxic factor or the replacement fluid used that is beneficial remains to be clarified.

Chronic inflammatory demyelinating polyneuropathy of infancy: a corticosteroid-responsive disorder

We present the clinical, electrophysiological, and histopathological findings in 6 children with early-onset chronic inflammatory demyelinating neuropathy. The clinical features initially suggested a genetically determined disorder in each patient. Sural nerve biopsy showed changes of chronic demyelination with multifocal endoneurial edema and mononuclear cellular infiltrates. All children improved with corticosteroid therapy.

Plasma exchange in chronic inflammatory demyelinating polyradiculoneuropathy

Plasma exchange has been reported to be efficacious in chronic inflammatory demyelinating polyradiculoneuropathy. We performed a prospective double-blind trial in which patients with static or worsening disease were randomly assigned to plasma exchange (n = 15) or to sham exchange (n = 14) for three weeks. After three weeks, we observed statistically significant differences in combined measurements of nerve conduction (total, motor, proximal, velocity, and amplitude) favoring patients who had received plasma exchange. Improvement to a greater degree than for any patient receiving sham exchange was detected in the neurologic-disability score in five patients (P = 0.025) and in subset scores for weakness and reflex in four patients (P less than 0.057). We conclude that for some patients with chronic inflammatory demyelinating polyradiculoneuropathy, plasma exchange has an ameliorating effect on neurologic dysfunction and nerve conduction, but in others no improvement is observed. Because plasma was replaced with normal serum albumin, a humoral factor or factors may have a role in the neurologic deficit of this disorder.

Treatment of peripheral neuropathies

There are three general approaches to treatment of peripheral neuropathy. First, an attempt should be made to reverse the pathophysiological process if its nature can be elucidated. Second, nerve metabolism can be stimulated and regeneration encouraged. Third, even if the neuropathy itself cannot be improved, symptomatic therapy can be employed. This review outlines the options available for each approach.

Plasma exchange in chronic inflammatory demyelinating polyradiculoneuropathy

Eleven consecutive patients with progressive chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) underwent plasma exchange. Eight patients were previously unresponsive to prednisone, two were started on prednisone with plasma exchange, and one did not receive corticosteroids. Electrodiagnostic studies revealed evidence of an acquired demyelinating polyradiculoneuropathy with varying degrees of axonal degeneration. Neurologic impairment was monitored using conventional functional status index. Five patients demonstrated substantial clinical improvement, beginning 2 days to 3 weeks after initiating plasma exchange. Two additional patients improved following a second course of plasma exchange, and four patients demonstrated minimal or no change. Comparison of responding and nonresponding patients showed no differences related to the presence or absence of antecedent illness, duration of disease, duration of maximum weakness, or severity of impairment prior to plasma exchange. Responders had significantly prolonged F-response and motor distal latencies compared to nonresponders. Results in this unselected, consecutive patient trial suggest a temporal relationship between plasma exchange and clinical improvement in some patients with progressive CIDP.

Chronic inflammatory polyneuropathy. Reduction of nerve conduction velocities in monkeys by systemic passive transfer of immunoglobulin G

In chronic (relapsing) inflammatory polyneuropathy (CRIP), successful treatment with plasma exchange has led to the concept of pathogenic humoral factors. In 6 patients with CRIP, 5 of whom improved after plasma exchange, the potential pathogenic role of circulating immunoglobulin (Ig) fractions was tested by applying the systemic passive transfer model to marmoset monkeys. After continuous treatment with intramuscular injections for 2-8 weeks, monkeys injected with the crude immunoglobulin fractions or with purified IgG from 5 of the 6 patients showed a significant and partially reversible reduction of the motor nerve conduction velocity (mean 34%, P less than 0.001) when compared with pre-treatment values. In control animals the reduction was 4%. Morphological examination revealed only minor ultrastructural changes of the myelin sheath. Immunocytochemistry revealed that human IgG was able to cross the blood-nerve barrier. It is concluded that the circulating IgG-fraction of patients with CRIP contains a factor that may contribute to the disordered nerve function after crossing the blood-nerve barrier. It may be the removal of this particular factor which is responsible for the rapid recovery of nerve conduction in patients after plasma exchange.

Therapeutic apheresis. Applications and future directions

The past 10-15 years have been witness to major technological achievements in the field of therapeutic apheresis. Concurrently, a large number of diseases, primarily with an immunological basis, have been treated with apheresis. In this paper, we review the various applications of therapeutic apheresis, adverse reactions associated with the mode of therapy, and future research directions. Several representative diseases are also discussed in detail.

Idiopathic inflammatory polyradiculoneuropathy: evaluation of clinical and laboratory data and therapeutic considerations

The clinical, immunological and neurophysiological data on 54 patients with idiopathic inflammatory polyradiculoneuropathy (IIP) are reviewed in order to reach a correct diagnostic and therapeutic approach. 49 of these patients presented acute and 5 recurrent IIP. Of the acute cases 10 patients had a severe course with paralysis of all limbs and respiratory insufficiency, and 3 died. An increase in CSF total proteins and impairment of nerve motor conduction velocities proved to be valuable tests for the diagnosis of IIP; these tests usually become more significant after 2 or 3 weeks of illness. Steroid treatment did not prove to be effective, while two patients with acute and progressive IIP, subjected to plasmapheresis, showed rapid and steady improvement. In these two patients the plasmapheresis was associated with azathioprine.

Plasma exchange in neurological diseases. A critical approach

The rationale for and results of plasma exchange (PE) in the therapy of different immune-mediated neurological diseases such as myasthenia gravis, multiple sclerosis, acute and chronic-relapsing Guillain-Barré syndromes, polymyositis, dermatomyositis and amyotrophic lateral sclerosis are reviewed. Dialysis dementia and Refsum's disease, subacute sclerosing panencephalitis and schizophrenia are mentioned, too. If we exclude the treatment of acute Guillain-Barré syndrome, where PE alone appears to be sufficient to produce recovery or improvement, the combined use of immunosuppressive drugs and/or lymphocytapheresis is probably needed in the treatment of the other diseases. PE allows the disease to be controlled rapidly while long-term pharmacological control is established. An underlying theme in this review is the need of adequately controlled studies or at least of large case lists with exhaustive reports concerning both positive and negative results since a new perspective is needed for this topic. Nonetheless, a number of uncontrolled observations suggest that probably PE effectiveness in most immune-mediated neurological diseases could be proven if the requisite trials were performed.

Plasma exchange in chronic inflammatory polyneuropathy: evidence suggestive of a pathogenic humoral factor

Chronic progressive of relapsing inflammatory polyneuropathy (CRIP) can be treated effectively with immunosuppressive drugs and/or plasma exchange (PE). This report describes a patient who responded dramatically and reproducibly to PE during four successive relapses and remained in remission while on medical immunosuppression with azathioprine and corticosteroids. The clinical course was closely correlated with electrophysiologic parameters such as compound muscle action potential amplitudes and distal latencies. The purified IgG fraction of PE filtrate bound to rat and human sciatic nerve on immunohistochemistry. Furthermore, a similar staining pattern was achieved by purified Fab fragments, which was absent in all control preparations. These findings support the hypothesis that circulating plasma factors may play a role in CRIP and that one of these factors may be an IgG antibody to peripheral nerve components.

Specificity of plasmapheresis in the treatment of chronic relapsing polyneuropathy

A 27-year-old woman with an eight year history of chronic relapsing polyneuropathy presented in her fifth relapse. Raised immune complexes prompted a trial of plasmapheresis. Remarkable clinical improvement was seen after the second exchange. Complete remission was obtained after ten treatments. Subsequently, further relapses have occurred, each responsive to plasmapheresis. The effect of plasma exchange in this patient appears to be unique as neither charcoal perfusion nor plasma infusion per se proved efficacious. The patient is currently maintained with weekly plasma exchanges, her course complicated by supervening hepatitis B antigenemia. The clearance of immune complexes observed during plasmapheresis raises the possibility that removal of a serum factor is responsible for her clinical improvement and that patients with such a factor may benefit from plasmapheresis.

Childhood chronic relapsing polyneuropathy: dramatic improvement following plasmapheresis

We present clinical data on two boys with chronic relapsing polyneuropathy. Their recurrent episodes of weakness had produced marked disability which was unresponsive to continuous prednisone therapy. Plasmapheresis produced dramatic improvement in muscle strength and functional ability. The remissions induced have been sustained despite withdrawal of steroid therapy.

Effects of plasmapheresis on the course of experimental allergic neuritis in rabbits

Experimental allergic neuritis was induced in 30 rabbits with extract of bovine peripheral nerve in complete Freund's adjuvant. Of the 22 animals that completed the study, nine animals were plasmapheresed within two weeks of inoculation and 13 animals served as controls. The plasmapheresed animals developed a less severe form of EAN than the controls. Differences were apparent in clinical weakness, weight loss, degree of dispersion of the muscle action potential and histological changes.

Autoantibody to nerve tissue in a patient with a peripheral neuropathy and an IgG paraprotein

The antibody activity of a benign IgG lambda paraprotein to nerve tissue in a case of peripheral neuropathy has been investigated using immunohistochemical methods on tyrpsin-treated, formalin-fixed, paraffin-embedded tissue. IgG lambda was found in th sural nerve biopsy of the patient. Specific binding of the purified IgG lambda paraprotein and its isolated F(ab')2 fragment to homologous nerve and brain tissue was demonstrated. Similar activity was not demonstrable on fresh frozen cryostat sections. The results suggest that tests for autoantibodies to nerve tissue in neuropathological disorders should not be confined to fresh frozen tissue substrates.

Treatment of Fisher's variant of Guillain Barré syndrome by exchange transfusion

A case of Fisher's variant of Guillain Barré Syndrome is presented. Treatment with exchange transfusion coincided with clinical improvement. This is the first case of Fisher's variant treated in this manner.

Chronic relapsing (dysimmune) polyneuropathy: pathogenesis and treatment

Chronic relapsing polyneuropathy is a distinct dysschwannian/demyelinating polyneuropathy characterized by usually slow onset, progressive or relapsing-remitting course, elevated cerebrospinal fluid (CSF) protein, marked slowing of nerve conduction velocity, segmental demyelination demonstrable in sural nerve biopsies, and absence of systemic illness or abnormal serum immunoglobulins. The cause of the disorder and the mechanisms underlying its chronicity and relapsing-remitting course are not clear. Immunoglobulin deposition observed in sural nerve biopsies and abnormal immunoglobulin patterns in the "CSF in some cases suggest a dysimmune pathogenesis; thus the term chronic relapsing (dysimmune) polyneuropathy (CRDP) is preferred. The disease is a treatable form of idiopathic polyneuropathy. In our series of 25 patients with CRDP, treatment with high-single-dose daily prednisone, slowly tapered to an alternate-day program, has been very successful in the majority. A low (10 to 20 mg) alternate-day-single-dose program, maintained indefinitely, seems to be required to prevent future recurrences. Evidence is provided that other immunosuppressants (azathioprine, cyclophosphamide, poly-ICLC) and possibly plasmapheresis, alone or in conjunction with corticosteroids, may have a beneficial role in controlling difficult cases of chronic relapsing polyneuropathy.

Treatment of acute inflammatory polyneuropathy

Most patients with acute inflammatory polyneuropathy (AIP) recover spontaneously, but the time course of the illness is unpredictable so that the results of treatment are difficult to assess. Three decades of retrospective reports of steroid treatment fail to demonstrate any striking beneficial effect. In a randomized trial of prednisolone, starting dose 60 mg daily, 21 treated patients improved more slowly than 19 untreated patients. By contrast, in rats immunized with bovine nerve root myelin, prednisolone at 10 mg/kg reduced the severity and duration of experimental allergic neuritis (EAN), the putative animal model for AIP. This discrepancy might reflect the greater difficulty of clinical as opposed to animal therapeutic trials or indicate that EAN is not the appropriate model for the human disease. Immunosuppressive drugs, plasmapheresis and other agents have also been employed, but their efficacy cannot be decided from the available case report. The role of similar agents in chronic progressive and relapsing inflammatory neuropathy cannot yet be resolved, but in some patients steroids do appear to be valuable.