Amyotrophic lateral sclerosis: an update

The aim is to review recent publications on amyotrophic lateral sclerosis (ALS).

The Awaji recommendations for electrophysiological diagnosis will permit earlier clinical trials entry. The use of ultrasound to visualize fasciculations, even in deep muscles, will contribute to earlier diagnosis, as well. Unfortunately, recent clinical trials in ALS have been disappointing, as illustrated by the negative lithium trials. New, less expensive, trial designs and the inclusion of patients early in the course of ALS are positive approaches for future trials. The search for ALS biomarkers continues and a number of encouraging reports have been published, but no features unique to ALS have yet transformed this field. The most exciting advances in ALS arise from protein studies and genetics. Recognition that the ubiquitinated cytosolic inclusions in sporadic ALS, as well as in some patients with frontotemporal dementia (FTD), contain TDP-43, and that some familial cases (and a few sporadic cases) have mutations of the TDP-43 gene has transformed previous concepts on ALS pathogenesis. Other newly recognized mutations linked to ALS, such as fused-in-sarcoma (FUS) and valosin-containing protein (VCP), have not only widened the spectrum of genes involved in ALS but also consolidated the close relation between ALS and FTD.

ALS research is entering a new phase that should generate new proposals regarding putative therapies, or strategies for disease treatment. A continuing difficulty, however, is early clinical diagnosis and, especially, the need for identification of a unique biomarker, sensitive to clinical change in the course of the disease.