Dramatic clinical response to ultra-high dose IVIg in otherwise treatment resistant inflammatory neuropathies

Abstract

Background

Intravenous immunoglobulin (IVIg) has short and long-term efficacy in both chronic inflammatory demyelinating polyneuropathy (CIDP) and multifocal motor neuropathy with conduction block (MMNCB). There is potential for under and over-treatment if trial regimens are strictly adhered to in clinical practice where titrating dose to clinical response is recommended.

Methods

We report the response to high-dose IVIg (>2 g/kg/6 weeks) in a subgroup of patients with definite CIDP or MMNCB who were unresponsive to ‘usual’ dosing. IVIg frequency and dosing was determined for each individual by subjective and objective outcome measures for impairment, grip strength, and activity and participation.

Results

Six patients (three with chronic inflammatory demyelinating polyneuropathy (CIDP), three with MMN) were included. Two patients (one CIDP and one MMNCB) returned to full-time work on fractionated IVIg doses of 5 g/kg/month and 9 g/kg/month. Patient three (CIDP) failed numerous other immunosuppressants but responded to short-term fractionated 4 g/kg/month of IVIg. Patient four has severe, refractory, childhood-onset CIDP, remains stable but dependent currently on 6.9 g/kg/month of IVIg. Patients five and six, both with MMNCB, required short term 4.5–5 g/kg/month to recover significant bilateral hand strength. No IVIg-related adverse events occurred in any individual.

Conclusions

These six cases demonstrate the safety and effectiveness of a treatment approach that includes individualised but evidence-based clinical assessment and, when necessary, high-doses of IVIg to restore patients’ strength and ability to participate in activities of daily activities. Careful patient selection is important.

Keywords:

• inflammatory neuropathy
• intravenous immunoglobulin
• therapeutic dosing
• outcome measure

Acknowledgements

The authors thank A. M. Rossor for his assistance in preparing the figure for Case 4.

Disclosure statement

The authors report no disclosures relevant to the manuscript.

MK gratefully received funding from a patient’s bequest. MM Reilly is grateful to the Medical Research Council (MRC), MRC Centre grant (G0601943), the National Institutes of Neurological Diseases and Stroke and office of Rare Diseases (U54NS065712) for their support. MM Reilly, MP Lunn and AS Carr are supported by the National Institute of Health Research, University College London Hospitals, Biomedical Research Centre.