What's new in chronic inflammatory demyelinating polyradiculoneuropathy in 2007-2008?

Randomized trial of intravenous immunoglobulin maintenance treatment regimens in chronic inflammatory demyelinating polyradiculoneuropathy

Background and purpose

High peak serum immunoglobulin G (IgG) levels may not be needed for maintenance intravenous immunoglobulin (IVIg) treatment in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and such high levels may cause side effects. More frequent lower dosing may lead to more stable IgG levels and higher trough levels, which might improve efficacy. The aim of this trial is to investigate whether high frequent low dosage IVIg treatment is more effective than low frequent high dosage IVIg treatment.

Methods

In this randomized placebo‐controlled crossover trial, we included patients with CIDP proven to be IVIg‐dependent and receiving an individually established stable dose and interval of IVIg maintenance treatment. In the control arm, patients received their individual IVIg dose and interval followed by a placebo infusion at half the interval. In the intervention arm, patients received half their individual dose at half the interval. After a wash‐out phase patients crossed over. The primary outcome measure was handgrip strength (assessed using a Martin Vigorimeter). Secondary outcome indicators were health‐related quality of life (36‐item Short‐Form Health Survey), disability (Inflammatory Rasch‐built Overall Disability Scale), fatigue (Rasch‐built Fatigue Severity Scale) and side effects.

Results

Twenty‐five patients were included and were treated at baseline with individually adjusted dosages of IVIg ranging from 20 to 80 g and intervals ranging from 14 to 35 days. Three participants did not complete the trial; the main analysis was therefore based on the 22 patients completing both treatment periods. There was no significant difference in handgrip strength change from baseline between the two treatment regimens (coefficient −2.71, 95% CI −5.4, 0.01). Furthermore, there were no significant differences in any of the secondary outcomes or side effects.

Conclusions

More frequent lower dosing does not further improve the efficacy of IVIg in stable IVIg‐dependent CIDP and does not result in fewer side effects.

Childhood chronic inflammatory demyelinating polyneuroradiculopathy--three cases and a review of the literature

BACKGROUND

Chronic inflammatory demyelinating polyneuroradiculopathy (CIDP) is an autoimmune disease of the peripheral nervous system, causing demyelination and even axonal degeneration. In children, abnormal gait as a first sign of muscle weakness is a frequent reason to seek medical attention. Diagnosis is made on the basis of clinical characteristics, electromyography and nerve conduction studies, and elevated protein in cerebrospinal fluid.

AIMS

We present three new cases of CIDP. The literature was reviewed in order to obtain more information on presentation, outcome and treatment strategies world-wide.

RESULTS

The course of disease can be relapsing-remitting or chronic-progressive. From case series it is known that first-line immunotherapy (intravenously administered immunoglobulin, corticosteroids or plasmapheresis) is initially of benefit in most children with CIDP. There is little evidence, however, on second-line therapies as azathioprine, cyclosporine A, mycophenolate mofetil, methothrexate, cyclophosphamide and IFN alpha. Although the outcome of children with CIDP is generally regarded to be good, disease related disability can be severe.

CONCLUSION

Childhood CIDP is rare. In general and in comparison to adults, children tend to have a more acute progressive onset, with more severe symptoms. Showing a higher tendency towards a relapsing-remitting course, children often show a better and faster improvement after therapy, and a more favorable outcome. Swift recognition of CIDP and empiric start of treatment are considered important to avoid potentially irreversible axonal damage and associated disability. Response to first-line therapies is usually favorable, however recommendations regarding the choice of second-line therapy can only be made on the basis of current practice described in case reports. Safety and efficacy data are insufficient. The cases described show that trial and error are often involved in finding an optimal treatment strategy, especially in those patients refractory to first-line treatment or with a prolonged course. Clinical experience with immunomodulatory treatment is paramount when treating children with CIDP.