There was not then and is not now a simple test that can tell a patient whether or not they have ALS. But a study published in this month's issue of Neurology may change that.
Researchers from Mount Sinai School of Medicine identified three proteins that are found in significantly lower concentration in the cerebral spinal fluid of patients with ALS than in healthy individuals. These are the first biomarkers for this disease.
"ALS is a very difficult disease to diagnose. To date, there is no one test or procedure to ultimately establish the diagnosis of ALS. It is through a clinical examination and series of diagnostic tests, often ruling out other diseases," website of the ALS Association.
Giulio Pasinetti, MD, PhD, Professor of Psychiatry, Neuroscience, and Geriatrics and Adult Development, Mount Sinai School of Medicine and colleagues compared cerebral spinal fluid from patients diagnosed with ALS, patients with other neurological disorders, and healthy individuals. They found that fluid from patients with ALS had significantly lower concentrations of three proteins than either of the other groups. Evaluating the levels of these three proteins proved 95% accurate for diagnosing ALS.
The researchers found that the changes in concentration of these proteins were evident within 1.5 years of onset of symptoms. With current methods, the average time from onset of symptoms to diagnosis is two years. Testing for these protein concentrations may provide a means of early diagnosis, allowing patients to receive relief from symptoms years earlier.
"For the first time we have the possibility of developing a test that can definitively say whether or not a patient has ALS," said Dr. Pasinetti. "Such a test would eliminate the need for patients to undergo months of diagnostic evaluation and remove the uncertainty that currently lingers with physicians and patients even after a diagnosis is made."