Chronic inflammatory demyelinating polyneuropathy after treatment with interferon-alpha

Neurological manifestations of COVID-19, SARS and MERS

Since December 2019, the world is affected by an outbreak of a new disease named COVID-19, which is an acronym of 'coronavirus disease 2019'. Coronaviruses (CoV) were assumed to be associated with mild upper respiratory tract infections, such as common cold. This perception changed in time due to occurrence of the Severe Acute Respiratory Syndrome (SARS) caused by SARS-CoV in 2002 and the Middle East Respiratory Syndrome (MERS) caused by MERS-CoV in 2012, both inducing an epidemic severe viral pneumonia with potentially respiratory failure and numerous extra-pulmonary manifestations. The novel coronavirus, SARS-CoV-2, is likewise a causative pathogen for severe viral pneumonia with the risk of progression to respiratory failure and systemic manifestations. In this review, we will give a summary of the neurological manifestations due to SARS and MERS, as those might predict the neurological outcome in the novel COVID-19. Additionally, we provide an overview of the current knowledge concerning neurological manifestations associated with COVID-19, to the extent that literature is already available as the pandemic is still ongoing.

Immunomodulatory treatment other than corticosteroids, immunoglobulin and plasma exchange for chronic inflammatory demyelinating polyradiculoneuropathy

BACKGROUND

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a disease that causes progressive or relapsing and remitting weakness and numbness. It is probably caused by an autoimmune process. Immunosuppressive or immunomodulatory drugs would be expected to be beneficial. This review was first published in 2003 and has been updated most recently in 2016.

OBJECTIVES

To assess the effects of immunomodulatory and immunosuppressive agents other than corticosteroids, immunoglobulin, and plasma exchange in CIDP.

SEARCH METHODS

On 24 May 2016, we searched the Cochrane Neuromuscular Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 4) in the Cochrane Library, MEDLINE, Embase, CINAHL, and LILACS for completed trials, and clinical trial registers for ongoing trials. We contacted the authors of the trials identified and other disease experts seeking other published and unpublished trials.

SELECTION CRITERIA

We sought randomised and quasi-randomised trials of all immunosuppressive agents, such as azathioprine, cyclophosphamide, methotrexate, ciclosporin, mycophenolate mofetil, and rituximab, and all immunomodulatory agents, such as interferon (IFN) alfa and IFN beta, in participants fulfilling standard diagnostic criteria for CIDP. We included all comparisons of these agents with placebo, another treatment, or no treatment.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. We wanted to measure the change in disability after one year as our primary outcome. Our secondary outcomes were change in disability after four or more weeks (from randomisation); change in impairment after at least one year; change in maximum motor nerve conduction velocity and compound muscle action potential amplitude after one year; and for participants who were receiving corticosteroids or intravenous immunoglobulin (IVIg), the amount of this medication given during at least one year after randomisation. Participants with one or more serious adverse events during the first year was also a secondary outcome.

MAIN RESULTS

Four trials fulfilled the selection criteria: one of azathioprine (27 participants), two of IFN beta-1a (77 participants in total) and one of methotrexate (60 participants). The risk of bias was considered low in the trials of IFN beta-1a and methotrexate but high in the trial of azathioprine. None of the trials showed significant benefit in any of the outcomes selected by their authors. The results of the outcomes which approximated most closely to the primary outcome for this review were as follows.In the azathioprine trial there was a median improvement in the Neuropathy Impairment Scale (scale range 0 to 280) after nine months of 29 points (range 49 points worse to 84 points better) in the azathioprine and prednisone treated participants compared with 30 points worse (range 20 points worse to 104 points better) in the prednisone alone group. There were no reports of adverse events.In a cross-over trial of IFN beta-1a with 20 participants, the treatment periods were 12 weeks. The median improvement in the Guy's Neurological Disability Scale (range 1 to 10) was 0.5 grades (interquartile range (IQR) 1.8 grades better to zero grade change) in the IFN beta-1a treatment period and 0.5 grades (IQR 1.8 grades better to 1.0 grade worse) in the placebo treatment period. There were no serious adverse events in either treatment period.In a parallel group trial of IFN beta-1a with 67 participants, none of the outcomes for this review was available. The trial design involved withdrawal from ongoing IVIg treatment. The primary outcome used by the trial authors was total IVIg dose administered from week 16 to week 32 in the placebo group compared with the IFN beta-1a groups. This was slightly but not significantly lower in the combined IFN beta-1a groups (1.20 g/kg) compared with the placebo group (1.34 g/kg, P = 0.75). There were four participants in the IFN beta-1a group and none in the placebo group with one or more serious adverse events, risk ratio (RR) 4.50 (95% confidence interval (CI) 0.25 to 80.05).The methotrexate trial had a similar design involving withdrawal from ongoing corticosteroid or IVIg treatment. At the end of the trial (approximately 40 weeks) there was no significant difference in the change in the Overall Neuropathy Limitations Scale, a disability scale (scale range 0 to 12), the median change being 0 (IQR -1 to 0) in the methotrexate group and 0 (IQR -0.75 to 0) in the placebo group. These changes in disability might have been confounded by the reduction in corticosteroid or IVIg dose required by the protocol. There were three participants in the methotrexate group and one in the placebo with one or more serious adverse events, RR 3.56 (95% CI 0.39 to 32.23).

AUTHORS' CONCLUSIONS

Low-quality evidence from randomised trials does not show significant benefit from azathioprine or interferon beta-1a and moderate-quality evidence from one randomised trial does not show significant benefit from a relatively low dose of methotrexate for the treatment of CIDP. None of the trials was large enough to rule out small or moderate benefit. The evidence from observational studies is insufficient to avoid the need for randomised controlled trials to discover whether these drugs are beneficial. Future trials should have improved designs, more sensitive outcome measures relevant to people with CIDP, and longer treatment durations.

Neurological Complications during Treatment of Middle East Respiratory Syndrome

Background and Purpose

Middle East respiratory syndrome (MERS) has a high mortality rate and pandemic potential. However, the neurological manifestations of MERS have rarely been reported since it first emerged in 2012.

Methods

We evaluated four patients with laboratory-confirmed MERS coronavirus (CoV) infections who showed neurological complications during MERS treatment. These 4 patients were from a cohort of 23 patients who were treated at a single designated hospital during the 2015 outbreak in the Republic of Korea. The clinical presentations, laboratory findings, and prognoses are described.

Results

Four of the 23 admitted MERS patients reported neurological symptoms during or after MERS-CoV treatment. The potential diagnoses in these four cases included Bickerstaff's encephalitis overlapping with Guillain-Barré syndrome, intensive-care-unit-acquired weakness, or other toxic or infectious neuropathies. Neurological complications did not appear concomitantly with respiratory symptoms, instead being delayed by 2–3 weeks.

Conclusions

Neuromuscular complications are not rare during MERS treatment, and they may have previously been underdiagnosed. Understanding the neurological manifestations is important in an infectious disease such as MERS, because these symptoms are rarely evaluated thoroughly during treatment, and they may interfere with the prognosis or require treatment modification.

A case of chronic inflammatory demyelinating polyradiculoneuropathy after treatment with pegylated interferon α-2a in a patient with chronic hepatitis B virus infection

We report the case of a 42-year-old man with chronic hepatitis B virus infection who developed weakness and paresthesia in the extremities 2 months after administration of pegylated interferon (Peg-IFN)α-2a. Nerve conduction studies conducted 6 months after onset showed abnormal temporal dispersions in both tibial nerves. We diagnosed chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) resulting from treatment with Peg-IFNα-2a. Neurological symptoms were prolonged despite suspension of the treatment. Subsequent treatment with intravenous immunoglobulin improved both clinical symptoms and temporal dispersion. IFNα-induced CIDP is rare, but can reportedly progress even after interruption of IFN-α without immunotherapy. Patients presenting with polyneuropathy after initiation of IFN-α thus require close attention.

Screening for Electrophysiological Abnormalities in Chronic Hepatitis C Infection: Peripheral Neuropathy and Optic Neuropathy

INTRODUCTION

To investigate the existence of peripheral and optic neuropathies in asymptomatic individuals with hepatitis C infection.

METHODS

Thirty consecutive patients who were followed in a hepatitis C outpatient clinic were recruited for electrophysiological evaluation together with 30 age- and gender-compatible healthy controls. All patients had a detailed neurological examination. The information regarding the disease duration and management with interferons were collected. Nerve conduction studies and visual evoked potentials (VEP) were recorded in all subjects. The results of the patient and control groups were statistically compared.

RESULTS

Of the patients with hepatitis C infection, 16 were females and 14 males. The mean age was 57.5 years, and the average disease duration was 6.43 years. The P100 latencies in the patient group were within normal limits, while the amplitudes were meaningfully small by comparison with the controls. There were some abnormalities in the nerve conduction studies of 15 patients. Sensorial neuropathy was detected in two patients, sensorimotor polyneuropathy in four, carpal tunnel syndrome in seven, and carpal tunnel syndrome and sensorimotor polyneuropathy as comorbid states in another two patients. The nerve conduction studies and VEP parameters were entirely normal in the control group.

CONCLUSION

Hepatitis C-related neurological abnormalities may occur both in the central and peripheral nervous system. Mononeuritis multiplex, sensorial axonal neuropathy, and multiple mononeuropathies are some of the presentations of the peripheral nervous system involvement. The mode of infection is considered to be via vasculitic mechanisms. In addition, optic neuropathy is a known complication of interferon treatment. Autoantibodies, cytokines, chemokines, and cryoglobulins are accused to play roles in the pathogenesis. In this study, we investigated the involvement of the peripheral nervous system and optic nerves in a group of patients with hepatitis C. The results were in favor of peripheral nerve injury of various types and optic neuropathy of the axonal type.

HCV-related central and peripheral nervous system demyelinating disorders

Chronic infection with hepatitis C virus (HCV) is associated with a large spectrum of extrahepatic manifestations (EHMs), mostly immunologic/rheumatologic in nature owing to B-cell proliferation and clonal expansion. Neurological complications are thought to be immune-mediated or secondary to invasion of neural tissues by HCV, as postulated in transverse myelitis and encephalopathic forms. Primarily axonal neuropathies, including sensorimotor polyneuropathy, large or small fiber sensory neuropathy, motor polyneuropathy, mononeuritis, mononeuritis multiplex, or overlapping syndrome, represent the most common neurological complications of chronic HCV infection. In addition, a number of peripheral demyelinating disorders are encountered, such as chronic inflammatory demyelinating polyneuropathy, the Lewis-Sumner syndrome, and cryoglobulin-associated polyneuropathy with demyelinating features. The spectrum of demyelinating forms also includes rare cases of iatrogenic central and peripheral nervous system disorders, occurring during treatment with pegylated interferon. Herein, we review HCV-related demyelinating conditions, and disclose the novel observation on the significantly increased frequency of chronic demyelinating neuropathy with anti-myelin-associated glycoprotein antibodies in a cohort of 59 consecutive patients recruited at our institution. We also report a second case of neuromyelitis optica with serum IgG autoantibody against the water channel aquaporin-4. The prompt recognition of these atypical and underestimated complications of HCV infection is of crucial importance in deciding which treatment option a patient should be offered.

Deregulated Fcγ receptor expression in patients with CIDP

Objective:

To evaluate the expression of activating and inhibitory Fc-gamma receptors (FcγRs) before and during clinically effective therapy with IV immunoglobulin (IVIg) in patients with chronic inflammatory demyelinating polyneuropathy (CIDP).

Methods:

Peripheral blood leukocyte subsets, including classical CD14^highCD16⁻ and nonclassical inflammatory CD14^lowCD16⁺ monocytes as well as naive CD19⁺CD27⁻ and memory CD19⁺CD27⁺ B cells, were obtained at baseline and monitored at 2 and 4–8 weeks after initiation of IVIg therapy.

Results:

Compared with healthy donors matched by age and sex, patients with CIDP showed increased expression levels of the activating high-affinity FcγR1 on CD14^highCD16⁻ (p < 0.001) and CD14^lowCD16⁺ monocytes (p < 0.001). Expression of the activating low-affinity FcγRIIA was increased on CD14^lowCD16⁺ monocytes (p = 0.023). Conversely, expression of the inhibitory FcγRIIB was reduced on naive (p = 0.009) and memory (p = 0.002) B cells as well as on CD14^highCD16⁻ monocytes (p = 0.046). Clinically effective IVIg therapy partially restored deregulated FcγR expression on B cell subsets and monocytes.

Conclusions:

The FcγR regulatory system is disturbed in patients with CIDP. Balancing activating vs inhibitory FcγR expression might provide a clinical benefit for patients with CIDP.

Patterns and significance of concomitant central and peripheral inflammatory demyelination

Inflammatory demyelinating diseases comprise a spectrum of disorders that affect central nervous system (CNS) and peripheral nervous system (PNS) myelin. Most individuals have demyelinating disease restricted to one or the other compartment but patients with concomitant CNS and PNS inflammatory inflammatory demyelinating processes have been reported not infrequently. In most such patients, involvement of either the CNS or the PNS predominates the clinical picture. Involvement of the other compartment is usually mild or subclinical with unclear prognostic and therapeutic implications. Similarly, while experimentally induced demyelinating disease in animal models is usually CNS or PNS predominant, varying degrees of pathology in the other system can occur depending on the species, type of immunogen, and genetic background of the immunized animal. When CNS and PNS demyelinating diseases occur concurrently, effective treatment for CNS disease can be safely combined with effective treatment for PNS disease.

Immunomodulatory treatment other than corticosteroids, immunoglobulin and plasma exchange for chronic inflammatory demyelinating polyradiculoneuropathy

BACKGROUND

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a disease causing progressive or relapsing and remitting weakness and numbness. It is probably due to an autoimmune process. Immunosuppressive or immunomodulatory drugs would be expected to be beneficial. This review was first published in 2003 and has been most recently updated in 2013.

OBJECTIVES

We aimed to review systematically the evidence from randomised trials of immunomodulatory and immunosuppressive agents other than corticosteroids, immunoglobulin and plasma exchange for CIDP.

SEARCH METHODS

On 9 July 2012, we searched the Cochrane Neuromuscular Disease Group Specialized Register (July 2012), CENTRAL (2012, Issue 6 in The Cochrane Library), MEDLINE (January 1977 to July 2012), EMBASE (January 1980 to July 2012), CINAHL (January 1982 to July 2012) and LILACS (January 1982 to July 2012). We contacted the authors of the trials identified and other disease experts seeking other published and unpublished trials.

SELECTION CRITERIA

We sought randomised and quasi-randomised trials of all immunosuppressive agents such as azathioprine, cyclophosphamide, methotrexate, ciclosporin, mycophenolate mofetil, and rituximab and all immunomodulatory agents such as interferon alfa and interferon beta, in participants fulfilling standard diagnostic criteria for CIDP.

DATA COLLECTION AND ANALYSIS

Two authors independently selected trials, judged their risk of bias and extracted data. We wanted to measure the change in disability after one year as our primary outcome. Our secondary outcomes were change in disability after four or more weeks (from randomisation), change in impairment after at least one year, change in maximum motor nerve conduction velocity and compound muscle action potential amplitude after one year and for those participants who were receiving corticosteroids or intravenous immunoglobulin, the amount of this medication given during at least one year after randomisation. Participants with one or more serious adverse events during the first year was also a secondary outcome.

MAIN RESULTS

Four trials fulfilled the selection criteria, one of azathioprine (27 participants), two of interferon beta-1a (77 participants in total) and one of methotrexate (60 participants). The risk of bias in the two trials of interferon beta-1a for CIDP and the trial of methotrexate was assessed to be low but bias in the trial of azathioprine was judged high. None of these trials showed significant benefit in the primary outcome (measured only in the methotrexate study) or secondary outcomes selected for this review. Severe adverse events occurred no more frequently than in the placebo groups for methotrexate and interferon beta-1a, but participant numbers were low. There was no adverse event reporting in the azathioprine study.

AUTHORS' CONCLUSIONS

The evidence from randomised trials does not show significant benefit from azathioprine, interferon beta-1a or methotrexate but none of the trials was large enough to rule out small or moderate benefit. The evidence from observational studies is insufficient to avoid the need for randomised controlled trials to discover whether these drugs are beneficial. Future trials should have improved designs, more sensitive outcome measures and longer durations.

Acute inflammatory demyelinating polyneuropathy after treatment with pegylated interferon alfa-2a in a patient with chronic hepatitis C virus infection: a case report

Introduction

The combination of polyethylene glycol (PEG)ylated interferon (pegylated interferon) and ribavirin has been shown to be an effective treatment for chronic hepatitis C virus. In general, common side effects related to this combination therapy are mild and are well tolerated. However, peripheral neuropathy including demyelinating polyneuropathy related to PEG-interferon α2a (pegylated interferon alfa-2a) is extremely rare. In the literature, only one case of acute inflammatory demyelinating polyneuropathy related to PEG-interferon α2a has been published previously.

Case presentation

To the best of our knowledge we present only the second case of acute inflammatory demyelinating polyneuropathy related to PEG-interferon α2a, occurring in a 63-year-old Caucasian man. He developed tingling, numbness, and weakness of his upper and lower extremities with acute neurological deficits after five weeks of a combination therapy with PEG-interferon α2a and ribavirin for chronic hepatitis C virus infection. His clinical course, neurological findings, and his electromyogram results were all consistent with acute inflammatory demyelinating polyneuropathy. Our patient recovered completely after interferon was stopped and symptomatic treatment and a further electromyogram showed a disappearance of neuropathy. Four weeks later, PEG-interferon α2a was reintroduced with a gradually increasing dose without any reappearance of neurological symptoms allowing hepatitis C seroconversion.

Conclusions

Recognition of this rare yet possible presentation is important for early and accurate diagnosis and treatment. This case report also suggests that the reintroduction of PEGylated interferon in patients who had presented with acute inflammatory demyelinating polyneuropathy related to interferon α may be safe, but this must be confirmed by further studies.

Chronic inflammatory demyelinating polyneuropathy due to the administration of pegylated interferon α-2b: a neuropathology case report

We report a 35-year-old man who developed weakness in his extremities five months after pegylated interferon α (IFNα)-2b was administered. The serum tumor necrosis factor-α (TNFα) was elevated and nerve conduction studies revealed demyelination both in the distal and intermediate segments. The sural nerve pathology showed mild demyelinating process. The cessation of IFNα and administration of intravenous immunoglobulin improved both his clinical symptoms and the temporal dispersion in motor nerve conduction study. IFNα-induced CIDP is presumably a transient immunological condition that requires immunomodulatory therapy. The elevated serum TNFα may implicate the degree of downstream autoimmunity induced by IFNα.

Treatment of chronic inflammatory demyelinating polyneuropathy

OPINION STATEMENT

Chronic inflammatory demyelinating polyneuropathy (CIDP) is an acquired, immune-mediated, non-length-dependent polyradiculoneuropathy that is progressive or relapsing over a period of at least 8 weeks, often evolving over time to a relatively symmetric pattern. Although the exact pathogenesis is unclear, it is thought to be mediated by both cellular and humoral reaction to the peripheral nerve myelin sheath involving nerve roots and proximal and distal nerves. Early medical treatment of CIDP is important to prevent axonal loss occurring as a secondary effect of progressive demyelination. Only three treatments for CIDP have demonstrated benefit in randomized controlled studies: corticosteroids, plasma exchange, and intravenous immunoglobulin. About 25% of patients fail to respond to these treatments or respond inadequately. These treatments have similar efficacy but differ significantly in cost and adverse effects. These factors are considered in treatment selection.

Autoimmune disorders affecting both the central and peripheral nervous system

Various case series of patients with autoimmune demyelinating disease affecting both the central and peripheral nervous system (CNS and PNS), either sequentially or simultaneously, have been reported for decades, but their frequency is considerably lower than that of the "classical" neurological autoimmune diseases affecting only either CNS or PNS, such as multiple sclerosis (MS), chronic inflammatory demyelinating polyneuropathy (CIDP) or Guillain-Barré-Syndrome (GBS), and attempts to define or even recognize the former as a clinical entity have remained elusive. Frequently, demyelination started with CNS involvement with subsequent PNS pathology, in some cases with a relapsing-remitting course. Three potential mechanisms for the autoimmune etiology of these conditions can be discussed: (I) They could be caused by a common autoimmunological reactivity against myelin antigens or epitopes present in both the central and peripheral nervous system; (II) They could be due to a higher general susceptibility to autoimmune disease, which in some cases may have been caused or exacerbated by immunomodulatory treatment, e.g. b-interferon; (III) Their co-occurrence might be coincidental. Another example of an autoimmune disease variably involving the central or peripheral nervous system or both is the overlapping and continuous clinical spectrum of Fisher syndrome (FS), as a variant of GBS, and Bickerstaff brainstem encephalitis (BBE). Recent data from larger patient cohorts with demonstration of common autoantibodies, antecedent infections, and results of detailed clinical, neuroimaging and neurophysiological investigations suggest that these three conditions are not separate disorders, but rather form a continuous spectrum with variable central and peripheral nervous system involvement. We herein review clinical and paraclinical data and therapeutic options of these disorders and discuss potential underlying common vs. divergent immunopathogenic mechanisms.

Immunomodulatory treatment other than corticosteroids, immunoglobulin and plasma exchange for chronic inflammatory demyelinating polyradiculoneuropathy

BACKGROUND

Chronic inflammatory demyelinating polyradiculoneuropathy is a disease causing progressive or relapsing and remitting weakness and numbness. It is probably due to an autoimmune process. Immunosuppressive or immunomodulatory drugs would be expected to be beneficial.

OBJECTIVES

We aimed to review systematically the evidence from randomised trials of cytotoxic drugs and interferons other than corticosteroids, immunoglobulin and plasma exchange for chronic inflammatory demyelinating polyradiculoneuropathy.

SEARCH STRATEGY

We searched the Cochrane Neuromuscular Disease Group Specialised Register (May 2010), The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 2), MEDLINE (January 1977 to May 2010), EMBASE (January 1980 to May 2010), CINAHL (January 1982 to May 2010) and LILACS (January 1982 to May 2010). We contacted the authors of the trials identified and other disease experts seeking other published and unpublished trials.

SELECTION CRITERIA

We sought randomised and quasi-randomised trials of all immunosuppressive agents such as azathioprine, cyclophosphamide, methotrexate, ciclosporin A, mycophenolate mofetil, and rituximab and all immunomodulatory agents such as interferon alfa and interferon beta in participants fulfilling standard diagnostic criteria for chronic inflammatory demyelinating polyradiculoneuropathy.

DATA COLLECTION AND ANALYSIS

Two authors independently selected trials, judged their methodological quality and extracted data. We wanted to measure the change in disability after one year as our primary outcome. Our secondary outcomes were change in disability after four or more weeks (from randomisation), change in impairment after at least one year, change in maximum motor nerve conduction velocity and compound muscle action potential amplitude after one year and for those participants who were receiving corticosteroids or intravenous immunoglobulin, the amount of this medication given during at least one year after randomisation. Participants with one or more serious adverse events during the first year was also a secondary outcome.

MAIN RESULTS

Four trials fulfilled the selection criteria, one of azathioprine (27 participants), two of interferon beta-1a (77 participants in total) and one of methotrexate (60 participants). None of these trials showed significant benefit in the primary outcome or secondary outcomes selected for this review.

AUTHORS' CONCLUSIONS

The evidence from randomised trials does not show significant benefit from azathioprine, interferon beta-1a or methotrexate but none of the trials was large enough to rule out small or moderate benefit. The evidence from observational studies is insufficient to avoid the need for randomised controlled trials to discover whether these drugs are beneficial. Future trials should have improved designs, more sensitive outcome measures and longer durations.

Pericarditis and chronic inflammatory demyelinating polyneuropathy during therapy with pegylated interferon alfa-2a for chronic hepatitis C

We report a case of pericarditis and chronic inflammatory demyelinating polyneuropathy with biological signs of a lupus-like syndrome due to pegylated interferon alfa-2a therapy during treatment for chronic hepatitis C. The patient developed moderate weakness in the lower limbs and dyspnea. He was hospitalized for congestive heart failure. An electrocardiogram showed gradual ST-segment elevation in leads V(1) through V(6) without coronary artery disease. A transthoracic cardiac ultrasonographic study revealed moderate pericardial effusion with normal left ventricular function. Anti-DNA antibody and antids DNA IgM were positive. Neurological examination revealed a symmetrical predominantly sensory polyneuropathy with impairment of light touch and pin prick in globe and stoking-like distribution. Treatment with prednisolone improved the pericarditis and motor nerve disturbance and the treatment with intravenous immunoglobulin improved the sensory nerve disturbance.

Demyelinating neuropathy in patients with hepatitis C virus infection

Infection with hepatitis C virus (HCV) can be associated with demyelinating polyneuropathy that may be responsive to immunomodulatory therapy. In this case report series, we review four patients (all male, ages 47-60 years) with HCV and demyelinating polyneuropathy. Two of the four patients were diagnosed with HCV during the course of initial neuropathy evaluation. All patients had sensory loss, absent/diminished reflexes, lower extremity weakness (except for one patient), and demyelinating electrodiagnostic features. Three patients had polyclonal hypergammaglobulinemia and one patient had IgM monoclonal gammopathy. Intravenous immunoglobulin resulted in improvement in three patients; one patient had no benefit from rituximab therapy, but his symptoms have been stable. Demyelinating neuropathy may develop in patients with HCV unrelated to antiviral therapy. Immunomodulatory therapy may be beneficial in some cases. Testing for HCV should be considered, especially in patients with hypergammaglobulinemia or IgM monoclonal gammopathy.

Chronic inflammatory demyelinating polyneuropathy: diagnosis and management

Over the course of 8 weeks, a 50-year-old man developed progressive bilateral leg and arm weakness, with numbness and tingling of the feet and hands. His symptoms persisted for 6 months, with impaired manual dexterity, arm weakness when brushing his teeth, tripping when walking, inability to climb stairs and gait imbalance. On examination, there is mild proximal and distal weakness of the upper and lower extremity muscles, length-dependent sensory loss of vibratory perception and joint position sense, areflexia, positive Romberg test and steppage gait with bilateral foot drop. Motor nerve conduction studies of the arms and legs show partial conduction blocks in several nerves with nonuniform slowing, and sensory responses are absent in the hands, however, normal sural responses are noted. Lumbar puncture reveals acellular cerebrospinal fluid with elevated protein. After 2 months following treatment, his strength and gait improved significantly, and his sensory symptoms resolved.

Guillain-Barre syndrome associated with peginterferon alfa-2a for chronic hepatitis C: A case report

The recommended therapy for chronic hepatitis C (CHC) infection is the combination of a Pegylated interferon and Ribavirin. Almost all such patients on combination therapy experience one or more adverse events during the course of treatment. Significant neurological side effects are rare. A few cases of Bell's Palsy, chronic inflammatory demyelinating polyneuropathy and even one case of acute demyelinating polyneuropathy with atypical features for Guillain-Barre syndrome (GBS) associated with Interferon therapy have been reported but no report of GBS with typical features has been published. We present a case report of typical GBS associated with Peginterferon alfa-2a and Ribavirin used for treatment of CHC infection.

Chronic inflammatory demyelinating polyneuropathy after treatment with interferon-alpha

Interferon-alpha (IFN-alpha), though widely used for the treatment of chronic viral hepatitis, may be associated with the occurrence of autoimmune disorders. In this case report, a patient with chronic hepatitis C virus infection had chronic inflammatory demyelinating polyneuropathy (CIDP) after the initiation of IFN-alpha therapy. The neurological symptoms of this patient continued to progress even though the treatment with IFN-alpha had been withdrawn; the symptoms improved dramatically following treatment with intravenous immunoglobulin. This case may therefore provide an important clue to understand the immune mechanism of CIDP and IFN-alpha.

Polyethylene glycol interferon alpha-2b-induced immune-mediated polyradiculoneuropathy

Polyethylene glycol-interferon alpha (PEG-IFNalpha) has been used as the standard treatment for hepatitis C virus (HCV) infection. There have been no previous reports of polyradiculoneuropathy with anti-ganglioside antibodies induced by PEG-IFNalpha-2b. We report a 59-year-old man who developed polyradiculoneuropathy during treatment with PEG-IFN alpha-2b for chronic HCV infection. Serum levels of anti-asialo-GM1 (GA1) and anti-GM1 antibodies were elevated. Cessation of therapy with double filtration plasmapheresis resulted in marked improvement in his symptoms accompanied by a reduction in the antibody level. PEG-IFN alpha-2b may induce peripheral neuropathy mediated by anti-GA1 and anti-GM1 antibodies.

Acute inflammatory demyelinating polyneuropathy associated with pegylated interferon α 2a therapy for chronic hepatitis C virus infection

The combination of pegylated interferon (Peg-IFN) and ribavirin is the standard of care for chronic hepatitis C virus (HCV) infection treatment. In general, common side effects related to this combination therapy are mild and are very well tolerated. However, peripheral neuropathy including demyelinating polyneuropathy related to Peg-IFN is extremely rare. We present the first case of an acute inflammatory demyelinating polyneuropathy (AIDP) associated with Peg-IFN-α 2a (Pegasys) after 16 wk of a combination therapy with Pegasys and ribavirin in a 65-year-old woman with chronic HCV infection. She developed tingling, numbness, and weakness of her upper and lower extremities and was hospitalized for acute neurological deficits. Her clinical course, neurological findings, an electromyogram (EMG), nerve conductions studies (NCS), muscle biopsy, and a sural nerve biopsy were all consistent with AIDP likely related to Pegasys use. The patient recovered completely with the use of intravenous immunoglobulin (IVIG) including physical therapy and neurological rehabilitation. It is very important that gastroenterologists and/or hepatologists recognize this rare neurological complication related to Peg-IFN treatment very early, since it requires a prompt discontinuation of therapy including an immediate referral to a neurologist for the confirmation of diagnosis, management, and the prevention of long-term neurological deficits.

From bench to bedside--experimental rationale for immune-specific therapies in the inflamed peripheral nerve

Guillain-Barré syndrome and chronic inflammatory demyelinating polyradiculoneuropathy are autoimmune-mediated inflammatory diseases of the PNS. In recent years, substantial progress has been made towards understanding the immune mechanisms that underlie these conditions, in large part through the study of experimental models. Here, we review the available animal models that partially mimic human Guillain-Barré syndrome and chronic inflammatory demyelinating polyneuropathy, and discuss the wide range of therapeutic approaches that have been successfully established in these models of inflammatory neuropathies. Transfer of this preclinical knowledge to patients has been far less successful, and inflammatory neuropathies are still associated with significant morbidity and mortality. We will summarize successful therapeutic trials in human autoimmune neuropathies to provide a vantage point for the transfer of experimental treatment strategies to clinical practice in immune-mediated diseases of the peripheral nerve.

Fulminant central nervous system demyelination associated with interferon-α therapy and hepatitis C virus infection

Hepatitis C virus (HCV) infection is common in the general population and may coincide with disease in the central and peripheral nervous system. Interferon-α (IFN-α) is used as treatment for HCV infection. The therapeutic benefit is assumed to result from activation of natural killer cells and CD8+ T cells. Despite its beneficial effects, it has been associated with a number of autoimmune disorders, such as chronic inflammatory demyelinating polyneuropathy and multiple sclerosis. Several clinical reports including magnetic resonance imaging exist, but neuropathological confirmation of MS associated with IFN-α therapy and HCV infection is lacking. We report a case of a female patient with chronic HCV infection who developed `acute MS'-like demyelinating disease after IFN-α administration, with extensive lesions throughout brain and thoracic spinal cord. The patient died after a disease duration of 6 months. Brain autopsy revealed Baló-like demyelinating plaques with positive HCV sequences within florid lesions. The development of fulminant demyelinating disease after administration of IFN-α suggests that autoimmune mechanisms such as T cell mediated tissue damage might be initiated or aggravated by IFN-α therapy. Additionally, the presence of HCV RNA within the demyelinated lesion indicates a possible role in triggering or propagating disease. Multiple Sclerosis 2007; 13: 1100—1106. http://msj.sagepub.com

Chronic Inflammatory Demyelinating Polyneuropathy

In 1975, clinical, electrodiagnostic, and pathologic features defined chronic inflammatory demyelinating polyneuropathy (CIDP). Subsequent reports have made it clear that demyelination is a cardinal feature of teh disorder. Over the past 30 years, variants have been described and associated systemic disorders identified. There continues to be discussion, however, as to how best to define CIDP and classify the disorders that are chronic, acquired, immune mediated, and demyelinating. Understanding the disorders allows clinicians to make appropriate treatment decisions. Some disorders originally considered as variants now are shown to have characteristic features that make them distinct from CIDP. It is imperative to recognize the differences between these disorders.

Lewis-Sumner syndrome in hepatitis C virus infection: a possible pathogenetic association with therapeutic problems

A patient with chronic hepatitis from hepatitis C virus (HCV) infection developed Lewis-Sumner syndrome (LSS). The neuropathy worsened after intravenous immunoglobulins, remitted after intravenous methylprednisolone, relapsed during interferon-alpha, but responded again to steroids continued for 68 weeks with clinical remission and without worsening of hepatitis. We are not aware of other reports of HCV infection and LSS. This association may be coincidental or related to a virus-triggered immune-mediated process. Although the coexistence of a dysimmune neuropathy with hepatitis makes problematic the choice of treatment, we emphasize that the patient's condition during treatment with steroids and the 46 following weeks without therapy has been excellent.

Side effects of interferon-alpha therapy

AIM

Interferon-alpha (IFN-alpha) has been extensively explored for its efficacy in various disease conditions and is currently used as a standard treatment in several of these. Its use is accompanied by a wide variety of possible side effects. These side-effects may hamper reaching and maintaining the dose needed for maximal therapeutic effect while their occurrence can outweigh clinical benefit of IFN-alpha treatment. This review addresses the toxicity profile of IFN-alpha, the presumed pathophysiology of the different side effects and the strategies to handle these.

METHODS

Computerized searches were used and cross-references of articles and books were checked.

RESULTS

Adverse effects due to IFN-alpha have been described in almost every organ system. Many side-effects are clearly dose-dependent. Taken together, occurrence of flu-like symptoms, hematological toxicity, elevated transaminases, nausea, fatigue, and psychiatric sequelae are the most frequently encountered. Although insight in the mechanisms accounting for IFN-alpha-related toxicities has improved in recent years, much remains to be elucidated. Guidelines on the management of these untoward sequelae are mostly based on clinical experience, while many side-effects can only be adequately handled by dose adjustment or cessation of treatment.

CONCLUSION

Further research on the mechanisms underlying both therapeutic effects and adverse events is warranted. Hopefully, this will lead to better identification of those patients who are likely to benefit from treatment without experiencing severe toxicities.

Diagnosis and treatment of chronic inflammatory demyelinating polyneuropathy

Chronic inflammatory demyelinating polyneuropathy (CIDP) is an immune-mediated acquired polyneuropathy that may lead to disability. CIDP is characterized by an autoimmune attack against peripheral nervous system myelin, by cellular and humoral mechanisms. Early diagnosis and treatment may yield better functional recovery, probably by minimizing secondary axonal loss from a primary demyelinating insult. Intravenous immunoglobulin and plasmapheresis are considered standard-of-care therapy in CIDP, based on randomized, double-blinded, placebo-controlled evidence. Corticosteroids, despite less robust evidence, are also considered standard therapy for CIDP. Other nonstandard therapies may work in refractory patients. These include azathioprine, cyclophosphamide, cyclosporine A, etanercept, interferon-alpha 2a, mycophenolate mofetil, and tacrolimus. Emerging therapies include interferon-beta 1a, rituximab, and high-dose cyclophosphamide without stem-cell rescue. Because most patients will require prolonged therapy, long-term side effects are important considerations.

Inflammatory neuropathies: an update on evaluation and treatment

Inflammatory neuropathies are a diverse group of illnesses sharing the pathologic characteristic of inflammation surrounding nerve fibers. They may be autoimmune, granulomatous, infectious, paraneoplastic, or paraproteinemic in origin. All can result in significant morbidity and rarely, death. It is critical to correctly diagnose these illnesses, as many respond well to treatment. In this paper, the diagnosis and latest developments in the treatment of the most common inflammatory neuropathies (Guillain-Barré syndrome, chronic inflammatory demyelinating polyradiculoneuropathy, neurosarcoidosis, anti-myelin-associated glycoprotein neuropathy, Sjögren's syndrome, paraneoplastic neuronopathy, and vasculitic neuropathies) will be discussed.

Vasculitic complications of interferon-alpha treatment for chronic hepatitis C virus infection: case report and review of the literature

Chronic infection with hepatitis C virus (HCV) may be complicated by the development of systemic vasculitis. Vasculitis is either caused by mixed cryoglobulinemia or a non-cryoglobulinemic vasculitis resembling polyarteritis nodosa (PAN). Antiviral treatment with interferon-alpha (IFN) and subsequent clearing of HCV mostly leads to improvement of vasculitic symptoms, but vasculitis may also be exacerbated and even cases of new onset of vasculitis may occur. Exacerbations of both cryoglobulinemic and PAN-type vasculitis in chronic HCV infection have been described under treatment with IFN. The most common symptom is vasculitic neuropathy. However, peripheral neuropathy in a HCV-infected patient treated with IFN may also be caused by direct neurotoxic or antiangiogenic effects of IFN itself, often requiring a nerve biopsy to establish the exact diagnosis. The clinical course of vasculitic complications of IFN treatment is variable and ranges from regression of symptoms despite continuation of IFN treatment to fatal exacerbations despite termination of IFN treatment and additional immunosuppressive therapy. In most cases of IFN-induced vasculitis, immunosuppressive therapy with corticosteroids has been employed, leading to improvement of symptoms. We report the case of a patient with chronic HCV infection who first developed cryoglobulinemic vasculitis after initiation of therapy with the polyethylene glycol (PEG)-conjugated form of IFN (PEG-IFN) and discuss it in the context of the relevant literature. First onset of cryoglobulinemic vasculitis after initiation of IFN therapy has not been described so far.

Exacerbation of chronic inflammatory demyelinating polyradiculoneuropathy during interferonbeta-1b therapy in a patient with childhood-onset multiple sclerosis

Interferonbeta-1b (IFNbeta-1b) is commonly used for relapsing-remitting multiple sclerosis (MS). We report a 23-year-old woman with childhood onset relapsing-remitting MS treated with IFNbeta-1b who developed overt chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) immediately after therapy. A baseline conduction study before IFNbeta-1b therapy revealed decreased motor conduction velocities and prolonged F wave latencies in several nerves, but there was no neurological sign indicating neuropathy. The existence of subclinical demyelinating neuropathy before IFNbeta-1b treatment was suggested, although the clinical criteria for CIDP were unfulfilled. Following two months of IFNbeta-1b therapy, numbness of her right upper and lower limbs progressively worsened and all tendon reflexes were depressed. Electrophysiologically, F waves were not evoked in any limbs except for the left ulnar and tibial nerves, which showed marked prolongation of F wave latencies. Moreover, subclinical hyperthyroidism developed in association with high titers of anti-thyroglobulin and antithyroid peroxydase antibodies, which were negative before IFNbeta-1b therapy. These findings indicated that peripheral demyelination worsened at the nerve roots after IFNbeta-1b therapy. In addition to the development of autoimmune thyroid disease, the patient now fulfilled the criteria for probable CIDP. Along with the results of a previous report demonstrating IFNbeta-induced CIDP development in patients with childhood MS, this case underscores IFNbeta as a potential risk factor for CIDP in patients with childhood onset MS.

Clinical evaluation and patterns of chemotherapy-induced peripheral neuropathy

PURPOSE

To determine the pattern of change in peripheral nerve function (as measured by vision, hearing, deep tendon reflexes, vibratory sense, cutaneous sensation, gait and balance, muscle strength, and orthostatic blood pressure) occurring among individuals receiving cancer treatment with known neurotoxic agents.

DATA SOURCES

A convenience sample of 16 participants with cancer who were receiving chemotherapy had their peripheral nerve function assessed at baseline and at 4 weeks and 12 weeks of treatment. Data were analyzed using plots and regression slopes to determine change over time in clinical measures of peripheral nerve function. Outcome variables were vision, hearing, deep tendon reflexes, vibratory sense, cutaneous sensation, gait and balance, muscle strength, and changes in orthostatic blood pressure.

CONCLUSIONS

This is the first prospective study to use comprehensive clinical measures of peripheral nerve and muscle changes resulting from combination chemotherapy or a biotherapy regimen. Alterations in vision, hearing, deep tendon reflexes, vibratory sense, cutaneous sensation, balance, muscle strength, and orthostatic blood pressure were noted, but gait remained unchanged.

IMPLICATIONS FOR PRACTICE

This study provides beginning evidence of the need for careful, ongoing assessment of treatment-induced peripheral neuropathy. Standardized clinical practice procedures that incorporate patient evaluation for peripheral neuropathy must still be developed. In addition, we must educate our patients about the functional changes they may expect, and we must develop strategies to assist them in managing limitations that they experience as a result of peripheral neuropathy.

Cytotoxic drugs and interferons for chronic inflammatory demyelinating polyradiculoneuropathy

BACKGROUND

Chronic inflammatory demyelinating polyradiculoneuropathy is a disease causing progressive or relapsing and remitting weakness and numbness. It is probably due to an autoimmune inflammatory process. Immunosuppressive or immunomodulatory drugs would be expected to be beneficial.

OBJECTIVES

We aimed to review systematically the evidence from randomised trials concerning cytotoxic drugs and interferons for chronic inflammatory demyelinating polyradiculoneuropathy.

SEARCH STRATEGY

We searched the Cochrane Neuromuscular Disease Group trials register (searched May 2004), MEDLINE (searched January 1977 to May 2004), EMBASE (January 1980 to May 2004), CINAHL (searched January 1982 to December 2001) and LILACS (searched January 1982 to December 2001). We contacted the authors of the trials identified and other disease experts seeking other published and unpublished trials.

SELECTION CRITERIA

We sought randomised and quasi-randomised trials of all immunosuppressive agents such as azathioprine, cyclophosphamide, methotrexate, cyclosporin A, mycophenolate mofetil, and rituximab and all immunomodulatory agents such as alpha interferon and beta interferon in participants fulfilling standard diagnostic criteria for chronic inflammatory demyelinating polyradiculoneuropathy.

DATA COLLECTION AND ANALYSIS

Two of us independently selected the trials which met our criteria, judged their methodological quality and extracted the data onto specially designed forms. We wanted to measure the change in disability after one year as our primary outcome measure.

MAIN RESULTS

We found one parallel group open trial of azathioprine for nine months involving 27 participants and another of interferon beta involving 10 participants in a double blind crossover trial with each treatment period lasting 12 weeks. Neither trial provided our primary outcome measure and neither showed a significant beneficial effect on any of the outcome measures selected by the authors or ourselves in the protocol for this review.

REVIEWERS' CONCLUSIONS

The evidence is inadequate to decide whether azathioprine, interferon beta or any other immunosuppressive drug or interferon is beneficial in chronic inflammatory demyelinating polyradiculoneuropathy.

Guillain-Barré syndrome during treatment with interferon α for hepatitis B

We describe a patient who developed acute demyelinating polyneuropathy on the sixth week of interferon (IFN)alpha therapy for chronic hepatitis B (HBV) infection. A 23-year-old man with chronic HBV infection had acute onset of demyelinating polyneuropathy shortly after completing a standard 6-week course of therapy with IFNalpha 2a. Clinical findings, electrodiagnostic studies and elevated cerebrospinal fluid protein levels without cells supported the diagnosis of Guillain-Barré syndrome (GBS). Other potential causes of GBS were ruled out. It remains unknown whether IFNalpha or the HBV infection itself was the cause of GBS, but it is evident that IFNalpha could not have prevented the development of GBS in our patient. We suggest that coexistent HBV infection and IFNalpha therapy may play a role in triggering an autoimmune response to peripheral nerve myelin.

Immunotherapy of idiopathic inflammatory neuropathies

Evaluation of peripheral neuropathy is a common reason for referral to a neurologist. Recent advances in immunology have identified an inflammatory component in many neuropathies and have led to treatment trials using agents that attenuate this response. This article reviews the clinical presentation and treatment of the most common subacute inflammatory neuropathies, Guillain-Barré syndrome (GBS) and Fisher syndrome, and describes the lack of response to corticosteroids and the efficacy of treatment with plasma exchange and intravenous immunoglobulin (IVIG). Chronic inflammatory demyelinating polyneuropathy, although sharing some clinical, electrodiagnostic, and pathologic similarities to GBS, improves after treatment with plasma exchange and IVIG and numerous immunomodulatory agents. Controlled trials in multifocal motor neuropathy have shown benefit after treatment with IVIG and cyclophosphamide. Also discussed is the treatment of less common inflammatory neuropathies whose pathophysiology involves monoclonal proteins or antibodies directed against myelin-associated glycoprotein or sulfatide. Little treatment data exist to direct the clinician to proper management of rare inflammatory neuropathies resulting from osteosclerotic myeloma; POEMS syndrome; vasculitis; Sjögren's syndrome; and neoplasia (paraneoplastic neuropathy).

Chemotherapy-induced peripheral neuropathy

While cancer remains an important public health concern, novel and enhanced treatment modalities have increased the length of survival of individuals diagnosed with the disease. The treatment of most cancers requires the use of chemotherapeutic agents to affect cure, maintain control of the disease, or provide palliation of symptoms. Although the use of chemotherapeutic agents can serve to prolong life, such agents are associated with significant side effects. Increasing clinical evidence suggests treatment of cancer with neurotoxic agents results in some degree of peripheral neuropathy. Specific drug categories implicated in the development of peripheral neuropathy are the plant alkaloids, interferons, antimitotics, taxanes, and platinum-based compounds. Drug-induced peripheral neuropathy is sensory, dose-related and cumulative and is usually delayed, appearing weeks after initiation of therapy. The number of individuals at risk for the development of chemotherapy-induced neuropathy is expected to increase proportionately with clinical protocols utilizing higher or more frequent dosing. As advanced cancer treatments and clinical trials can result in extending the lives of individuals affected by cancer, long-term functional deficits resulting from life-saving treatments must now be addressed. As such, peripheral neuropathy has emerged as an important consequence of cancer therapy.

Chronic Inflammatory Demyelinating Polyradiculoneuropathy (CIDP): A Review of Clinical Syndromes and Treatment Approaches in Clinical Practice

Chronic inflammatory demyelinating polyneuropathy (CIDP) is a chronic, acquired immune and inflammatory disorder of the peripheral nervous system. The classic form of the disorder is manifested by progressive or relapsing proximal or generalized limb weakness and areflexia, and usually easily recognized; it is the large number of regional and functional variants and variety of associated illnesses that pose a challenge to the clinician in practice. Similarly, laboratory and electromyography criteria have been developed to confirm the diagnosis; however, these various schemes are contrived because only 50% to 60% of patients with typical clinical features of CIDP fulfill these strict electrodiagnostic research criteria. Several studies have established the efficacy of immune therapies such as corticosteroids, plasma exchange, and intravenous immune globulin as the mainstay of treatment of CIDP, but these treatments might provide only short-term benefit. This review offers an approach to the evaluation and management of patients with CIDP and highlights the difficult clinical problems in those who do not respond or frequently relapse after treatment with standard therapies such as patients with CIDP and concomitant axonal loss, and the assessment of those with CIDP and concurrent diseases such as diabetes mellitus.

Management of chronic inflammatory demyelinating polyradiculoneuropathy

This review briefly describes current concepts concerning the nosological status, pathogenesis and management of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). CIDP is an uncommon variable disorder of unknown but probably autoimmune aetiology. The commonest form of CIDP causes more or less symmetrical progressive or relapsing weakness affecting proximal and distal muscles. Against this background the review describes the short-term responses to corticosteroids, intravenous immunoglobulin (IVIg) and plasma exchange that have been confirmed in randomised trials. In the absence of better evidence about long-term efficacy, corticosteroids or IVIg are usually favoured because of convenience. Benefit following introduction of azathioprine, cyclophosphamide, cyclosporin, other immunosuppressive agents, and interferon-beta and -alpha has been reported but randomised trials are needed to confirm these benefits. In patients with pure motor CIDP and multifocal motor neuropathy, corticosteroids may cause worsening and IVIg is more likely to be effective. General measures to rehabilitate patients and manage symptoms, including foot drop, weak hands, fatigue and pain, are important.

Cytotoxic drugs and interferons for chronic inflammatory demyelinating polyradiculoneuropathy

BACKGROUND

Chronic inflammatory demyelinating polyradiculoneuropathy is a disease causing progressive or relapsing and remitting weakness and numbness. It is probably due to an autoimmune inflammatory process. Immunosuppressive or immunomodulatory drugs would be expected to be beneficial.

OBJECTIVES

We aimed to review systematically the evidence from randomised trials concerning cytotoxic drugs and interferons for chronic inflammatory demyelinating polyradiculoneuropathy.

SEARCH STRATEGY

We searched the Cochrane Neuromuscular Disease Group trials register (searched December 2001), MEDLINE (searched January 1977 to December 2001), EMBASE (January 1980 to December 2001), CINAHL (searched January 1982 to December 2001) and LILACS (searched January 1982 to December 2001). We contacted the authors of the trials identified and other disease experts seeking other published and unpublished trials.

SELECTION CRITERIA

We sought randomised and quasi-randomised trials of all immunosuppressive agents such as azathioprine, cyclophosphamide, methotrexate, cyclosporin A, mycophenolate mofetil, and rituximab and all immunomodulatory agents such as alpha interferon and beta interferon in participants fulfilling standard diagnostic criteria for chronic inflammatory demyelinating polyradiculoneuropathy.

DATA COLLECTION AND ANALYSIS

Two of us independently selected the trials which met our criteria, judged their methodological quality and extracted the data onto specially designed forms. We wanted to measure the change in disability after one year as our primary outcome measure.

MAIN RESULTS

We found one parallel group open trial of azathioprine for nine months involving 27 participants and another of interferon beta involving 10 participants in a double blind crossover trial with each treatment period lasting 12 weeks. Neither trial provided our primary outcome measure and neither showed a significant beneficial effect on any of the outcome measures selected by the authors or ourselves in the protocol for this review.

REVIEWER'S CONCLUSIONS

The evidence is inadequate to decide whether azathioprine, interferon beta or any other immunosuppressive drug or interferon is beneficial in chronic inflammatory demyelinating polyradiculoneuropathy.

Severe exacerbation of hepatitis C-associated vasculitic neuropathy following treatment with interferon alpha: a case report and literature review

Vasculitic neuropathy may occur in association with chronic hepatitis C infection. Interferon alpha (IFN(alpha)), an effective treatment for chronic hepatitis C, can precipitate or worsen autoimmune diseases. We report a patient with chronic hepatitis C and mild indolent vasculitic sensorimotor peripheral polyneuropathy, who developed severe mononeuropathy multiplex soon after IFN(alpha) was initiated, and review the literature on worsening vasculitic neuropathy after IFN(alpha) treatment for chronic hepatitis C. Care should be taken after starting patient with chronic hepatitis C-associated vasculitic neuropathy on IFN(alpha), as there is evidence that IFN(alpha) may exacerbate the neuropathy.

Combined adjuvant radiation and interferon-alpha 2B therapy in high-risk melanoma patients: the potential for increased radiation toxicity

PURPOSE

Surgically resected melanoma patients with high-risk features commonly receive adjuvant therapy with interferon-alpha 2b combined with radiation therapy; the purpose of our study was to evaluate the potential enhancement of radiation toxicity by interferon.

METHODS AND MATERIALS

Patients at LDS Hospital and the University of Utah Medical Center in Salt Lake City treated with interferon during radiotherapy or within 1 month of its completion were retrospectively identified, and their charts were reviewed. If possible, the patients were asked to return to the LDS Hospital radiation therapy department for follow-up.

RESULTS

Five of 10 patients receiving interferon-alpha 2b therapy during radiation therapy or within 1 month of its completion experienced severe subacute/late complications of therapy. Severe subacute/late complications included two patients with peripheral neuropathy, one patient with radiation necrosis in the brain, and two patients with radiation necrosis in the s.c. tissue. One patient with peripheral neuropathy and one patient with radiation necrosis also developed lymphedema.

CONCLUSIONS

In vitro studies have identified a radiosensitizing effect by interferon-alpha on certain cell lines, which suggests the possibility that patients treated with interferon and radiation therapy may experience more severe radiation toxicities. We have observed severe subacute/late complications in five of 10 patients treated with interferon-alpha 2b during radiation therapy or within 1 month of its completion. Although an observational study of 10 patients lacks the statistic power to reach conclusions regarding the safety and complication rates of combined interferon and radiation therapy, it is sufficient to raise concerns and suggest the need for prospective studies.