P7-7 The condition of bone marrow-MSCs of ALS patients is strongly associated with their prognosis

Abstract

Objective: Development of an electrophysiological biomarker of corticospinal tract (CST) degeneration for application as an electrodiagnostic test in Amyotrophic Lateral Sclerosis (ALS). ALS is a sporadic, progressive and fatal neurodegenerative disorder, which is characterised by loss of motoneurones within the brainstem and spinal cord, and degeneration of corticospinal tract (CST) neurons. While electrodiagnostic techniques for identifying motoneurone degeneration in ALS are well established, those for CST disease are not. We now have evidence from experiments in macaque monkeys that 15 30Hz intermuscular coherence (IMC), which is a measure of coupling between two EMG signals in the 15 30Hz frequency range, can be used to assess the integrity of the CST. We have therefore begun investigating the utility of IMC as an electrodiagnostic test in ALS patients. Methods: IMC was measured in 23 patients with ALS, including 10 patients with primary lateral sclerosis (PLS), the pure upper motor neurone variant of ALS in which there is only CST degeneration, and 6 patients with progressive muscular atrophy (PMA) the pure lower motor neurone variant of ALS. We also performed similar measures on healthy age-matched controls. Results: Significant 15 30Hz IMC was found in all patients with PMA, all age-matched controls (n = 15) and all non age-matched controls (n = 20) tested to date. However, none of the patients with PLS had significant 15 30Hz IMC. Conclusions: 15 30Hz IMC is dependent upon an intact CST and appears to be an inexpensive, simple and robust measure of CST degeneration in ALS. We are now investigating the diagnostic sensitivity and specificity of 15 30Hz IMC prospectively in a group of patients with clinically suspected/possible ALS, in which a significant proportion are likely to have an ALS mimic syndrome.