Clinical significance of cation channel antibodies in motor neuron disease.

INTRODUCTION

Antibodies against cation channels, including voltage-gated potassium channel (VGKC) complex, voltage-gated calcium channel (VGCC), and ganglionic acetylcholine receptor (gAChR), are detected in subgroups of autoimmune disorders, and rarely occur in motor neuron disease (MND).

METHODS

This investigation was a case-control study of 28 MND patients positive for cation channel antibodies in comparison with 56 age/gender/onset/diagnostic-category-matched MND patients without such antibodies.

RESULTS

One or more cation channel antibodies were detected in 6.9% of MND patients, mostly at low titers. The rate of MND progression determined by the revised ALS Functional Rating Scale-revised (ALSFRS-R) and Kaplan-Meier survival analysis was statistically indistinguishable between the antibody-positive and control groups. Incidence rates of cancer and coexisting autoimmune disorders were similar between both groups, based on non-comprehensive screening.

CONCLUSION

Cation channel antibodies in MND patients do not appear to affect disease progression. Routine testing for paraneoplastic antibodies is probably of limited usefulness in most MND patients. Muscle Nerve 54: 228-231, 2016.