Management of chronic inflammatory demyelinating polyradiculoneuropathy

Maintenance IV immunoglobulin treatment in chronic inflammatory demyelinating polyradiculoneuropathy

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) patients treated with intravenous immunoglobulin (IVIg) usually start with a standard dosage of 2 g/kg bodyweight. Only a minority of patients has a sustained improvement, and most require ongoing maintenance treatment. Preferred IVIg regimens, however, vary considerably between doctors and at present it is unknown which is optimal. As there are also large differences in IVIg dosage and interval requirements between patients, optimal IVIg maintenance treatment of CIDP is even more complex. The lack of evidence-based guidelines on how IVIg maintenance treatment should be administered may potentially lead to under- or overtreatment of this expensive therapy. We provide an overview of published practical IVIg maintenance treatment regimens, IVIg maintenance schedules used in randomized controlled trials and one based upon our own long-term experience on how this treatment could be given in CIDP.

Dimethyl Fumarate Ameliorates Lewis Rat Experimental Autoimmune Neuritis and Mediates Axonal Protection

BACKGROUND

Dimethyl fumarate is an immunomodulatory and neuroprotective drug, approved recently for the treatment of relapsing-remitting multiple sclerosis. In view of the limited therapeutic options for human acute and chronic polyneuritis, we used the animal model of experimental autoimmune neuritis in the Lewis rat to study the effects of dimethyl fumarate on autoimmune inflammation and neuroprotection in the peripheral nervous system.

METHODS AND FINDINGS

Experimental autoimmune neuritis was induced by immunization with the neuritogenic peptide (amino acids 53-78) of P2 myelin protein. Preventive treatment with dimethyl fumarate given at 45 mg/kg twice daily by oral gavage significantly ameliorated clinical neuritis by reducing demyelination and axonal degeneration in the nerve conduction studies. Histology revealed a significantly lower degree of inflammatory infiltrates in the sciatic nerves. In addition, we detected a reduction of early signs of axonal degeneration through a reduction of amyloid precursor protein expressed in axons of the peripheral nerves. This reduction correlated with an increase of nuclear factor (erythroid derived 2)-related factor 2 positive axons, supporting the neuroprotective potential of dimethyl fumarate. Furthermore, nuclear factor (erythroid derived 2)-related factor 2 expression in Schwann cells was only rarely detected and there was no increase of Schwann cells death during EAN.

CONCLUSIONS

We conclude that immunomodulatory and neuroprotective dimethyl fumarate may represent an innovative therapeutic option in human autoimmune neuropathies.

Predicting treatment response in chronic, acquired demyelinating neuropathies

Chronic inflammatory demyelinating polyradiculopathy is an immune-mediated neuropathy that was first described approximately 30 years ago. Since that time an increasingly wide spectrum of chronic acquired demyelinating polyneuropathies exhibiting different phenotypes, clinical course and treatment responses to immunomodulatory treatment have been described. Several new therapeutic agents have been prescribed for such conditions, some with promising results. This review summarizes what is presently known about the clinical courses, treatment responses and predictors of response of the chronic inflammatory demyelinating polyradiculopathy subgroups.

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.

Cyclosporin treatment in three children with chronic inflammatory demyelinating neuropathy

Chronic inflammatory demyelinating neuropathy is an uncommon acquired polyneuropathy in children. Oral prednisolone, intravenous methyl prednisolone, and intravenous immunoglobulin are its main initial therapies. In patients resistant to these modalities, other immunosuppressants can be used. We demonstrate the efficacy of cyclosporin in three children with chronic inflammatory demyelinating neuropathy. Two of them were infants. None had adverse effects, except for hirsutism. We conclude that cyclosporin treatment can be effective and safe in chronic inflammatory demyelinating neuropathy, when standard treatments are ineffective. Cyclosporin can also be used safely in infants.

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.

Pathogenesis of chronic inflammatory demyelinating polyradiculoneuropathy

The acute lesions of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) consist of endoneurial foci of chemokine and chemokine receptor expression and T cell and macrophage activation. The myelin protein antigens, P2, P0, and PMP22, each induce experimental autoimmune neuritis in rodent models and might be autoantigens in CIDP. The strongest evidence incriminates P0, to which antibodies have been found in 20% of cases. Failure of regulatory T-cell mechanism is thought to underlie persistent or recurrent disease, differentiating CIDP from the acute inflammatory demyelinating polyradiculoneuropathy form of Guillain-Barré syndrome. Corticosteroids, intravenous immunoglobulin and plasma exchange each provide short term benefit but the possible long-term benefits of immunosuppressive drugs have yet to be confirmed in randomised, controlled trials.

Treatment of chronic inflammatory demyelinating polyneuropathy

PURPOSE OF REVIEW

Chronic inflammatory demyelinating poly(radiculo)neuropathy (CIDP) is a treatable disorder. There are three proven effective treatments available. Randomized controlled trials have only focused on short-term effects, but most patients need long-term therapy. The most up-to-date treatment options are discussed. Attention is also paid to the use of appropriate assessment scales and treatment of residual findings.

RECENT FINDINGS

A Cochrane review is available indicating that intravenous immunoglobulin is an effective treatment. Equal efficacy of intravenous immunoglobulin and steroids was shown during a 6-week treatment period. New open studies indicated possible efficacy for mycophenolate, interferon-beta and etanercept. Combinations of treatment are scarcely studied yet. Some CIDP patients may have a more acute onset of disease since maximum severity is reached within 4-8 weeks, resulting in confusion about the diagnosis. It was shown that severe fatigue can be a major complaint in CIDP patients; a training regimen might partially resolve these problems.

SUMMARY

CIDP is a treatable disorder, but most patients need long-term treatment. Intravenous immunoglobulin, steroids and plasma exchange are shown to be effective. It is suggested that other immunomodulatory agents can also be effective, but randomized trials are needed to confirm these benefits. General measures to rehabilitate patients and to manage symptoms like fatigue and other residual findings are important.

Treatment of Guillain-Barre syndrome and CIDP

Guillain-Barré syndrome (GBS) and chronic inflammatory demyelinating poly-(radiculo)neuropathy (CIDP) are immune-mediated disorders with a variable duration of progression and a range in severity of weakness. Infections can trigger GBS and exacerbate CIDP. Anti-ganglioside antibodies are important, but there is debate on the role of genetic factors in the pathogenesis of these disorders. Randomized controlled trials (RCT) have shown that intravenous immunoglobulin (IVIg) and plasma exchange (PE) are effective in both GBS and CIDP. Most CIDP patients also improve after steroid therapy. Despite current treatment options, many patients have residual deficits or need to be treated for a long period of time. Therefore, new treatment trials are highly indicated. This review focuses on the current and possible new treatment options that could be guided by recent results from laboratory experiments.