ALS diagnostic criteria of El Escorial Revisited: do they meet the needs of clinicians as well as researchers?

The El Escorial criteria for diagnosis of amyotrophic lateral sclerosis (ALS) have been in use for almost a decade. A revised set of criteria, meant to supersede the original set, was developed at a 1998 World Federation of Neurology (WFN) ALS meeting at Airlie House in Warrenton, Virginia, USA. This revised document, nicknamed El Escorial Revisited, has been published on the WFN-ALS website. El Escorial has proven useful in standardizing diagnostic criteria for entry into research trials and it is expected that El Escorial Revisited will help to liberalize such entry requirements. However, general neurologists and neuromuscular clinicians have found El Escorial to be unwieldy and generally unhelpful in achieving an earlier, accurate diagnosis of ALS. The El Escorial Revisited document is a step toward lessening these problems, but more 'user-friendly' criteria may be necessary for clinicians and those not conducting research. Such ALS criteria would improve categorization of ALS patients, would allow clinicians more latitude in beginning ALS treatment, and would educate practitioners to differentiate ALS from other motor neuron and non-motor neuron diseases. Intensive education of physicians will help improve earlier patient referral and accurate ALS diagnosis. There remains a group of 'difficult cases' that will continue to challenge the neuromuscular specialist. Earlier diagnosis in this latter group will require significant advances in the fields of electrodiagnosis, neuroimaging, immunobiochemistry, and neurogenetics.