Optimization of Intravenous Immunoglobulin in Chronic Inflammatory Demyelinating Polyneuropathy Evaluated by Grip Strength Measurement

Abstract

Background: Optimal dose and timing of repeated intravenous immunoglobulin therapy (IVIg) for intractable chronic inflammatory demyelinating polyneuropathy (CIDP) patients have not been determined. The aim of this study was to optimize dose and timing of IVIg for CIDP patients who need frequent IVIg using daily grip strength measurement. Methods: Repeated IVIg were administered for two intractable CIDP patients. Grip strength was recorded at home every day to access the clinical change in symptoms, and dose and timing of IVIg were optimized based on the results. Results: The decrement on grip strength was a sensitive indicator of symptom exacerbation. 100 g of IVIg had a limited effect for each patient. In one patient, symptoms maintained after monthly 60 g of IVIg. In another, 100 g of IVIg every 7 weeks resulted in a marked improvement. After receiving 20 g of IVIg weekly, each patient showed further improvement. Conclusion: Optimal dose and timing possibly vary in each individual patient. Dose titration of IVIg is necessary to avoid over- and undertreatment. The daily self-monitoring of grip strength is a helpful tool for clinical assessment in CIDP.

Long‐term Immunoglobulin therapy for chronic inflammatory demyelinating polyradiculoneuropathy

“…Myometry has been shown to be a potentially useful tool to monitor disease activity in CIDP, and it is now used more commonly, although with varied methods, in many units. The independent usefulness of grip myometry has been further documented in recent literature . That myometry has the potential to be valuable is unquestionable; however, inter‐ and intrarater reliability may be an issue.…”

Rapid and reversible responses to IVIG in autoimmune neuromuscular diseases suggest mechanisms of action involving competition with functionally important autoantibodies

“…Symptomatic improvement following IVIG in CIDP, multifocal motor neuropathy (MMN), and MG is transient, and the IVIG must be administered repeatedly at intervals ≤3-4 weeks to maintain its clinical effect (Ruegg et al, 2004;Harbo et al, 2009b;Lin et al, 2011;Pollard and Armati, 2011). Recent reports of individualized regimens show that 28%-60% of CIDP patients require IVIG every 2 weeks or even more frequently for optimal maintenance of strength (Broyles et al, 2013;Kokubun et al, 2013;Kuitwaard et al, 2013;Rajabally et al, 2013). In contrast to transient relief of symptoms, true remission often requires immunomodulators other than IVIG, as shown in Fig.…”

Maintenace therapy in chronic inflammatory demyelinating polyradiculoneuropathy

“…In the Kokubun et al . study, improvement was demonstrated using grip strength, which was shown by Vanhoutte et al . to be a more sensitive outcome measure than the inflammatory neuropathy cause and treatment (INCAT) disability score.…”

“…The stated goal is to reduce the amount IVIg to the lowest effective dose so as to prevent overtreatment. However, some patients may benefit from escalation in their maintenance dose beyond that provided by standard treatment . How one determines that optimal dose is not always obvious.…”

“…In the pivotal trial of IVIg in CIDP, the dose was 1 g/kg every 3 weeks . Kokubun and colleagues reported that some patients do better with higher than standard maintenance doses of IVIg . Dose escalation has also been reported to be beneficial in some patients with multifocal motor neuropathy .…”