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 that mimic ALS, that a diagnosis can be established. A comprehensive diagnostic workup includes most, if not all, of the following procedures:
electrodiagnostic tests including electomyography (EMG) and nerve conduction velocity (NCV)
blood and urine studies including high resolution serum protein electrophoresis, thyroid and parathyroid hormone levels and 24 hour urine collection for heavy metals
x-rays, including magnetic resonance imaging (MRI)
myelogram of cervical spine
muscle and/or nerve biopsy
thorough neurological examination
These tests are done at the discretion of the physician, usually based on the results of other diagnostic tests and the physical examination. There are several diseases that have some of the same symptoms as ALS and most of these conditions are treatable. It is for this reason that The ALS Association recommends that a person diagnosed with ALS seek a second opinion from an ALS "expert" - someone who diagnoses and treats many ALS patients and has training in this medial specialty.