ISIS Survey: an international study on the diagnostic process and its implications in amyotrophic lateral sclerosis

In a number of ALS patients, a long delay between onset of symptoms and diagnosis is reported. In this international study (ISIS Survey) we have identified the pathway followed by ALS patients from first symptoms to diagnosis confirmation. Diagnostic data from a total of 201 patients with definite ALS from 6 countries (Argentina, Brazil, Germany, Italy, Spain and the USA) were analyzed. The median time needed to confirm diagnosis was found to be 14 months; time to first consultation took 2 months, time to consultation with a neurologist took 8 months, and time for observation and diagnostic assessment by the neurologist took 4 months. This time delay was shorter when presentation was at bulbar level and when fasciculations were present. The major causes of diagnostic delay were unfamiliarity of the physician with the disease, unusual clinical presentation, coexistence of other diseases to which clinical symptomatology was attributed, misleading findings or misinterpretation of neuro-radiological or neurophysiological findings. The diagnostic delay has several implications for patients and their families, including mismanagement, delay in establishing appropriate and individualized pharmacological and symptomatic therapies, and difficulty in planning personal and familiar future.