Already the typical combination of symptoms indicates an ALS. Then the physician carries out an electromyography (EMG). This helps identify damages in the transfer between the nerve and the muscle. In this way, one can more accurately recognize the stage of the disease. Further tests are MRT, blood tests or a muscle biopsy.
The neurologist also tests the reflexes, which could be changed by the disease progress. After the diagnosis, regular follow-up exams are necessary, to follow the progress of the damages and to check the breathing. Since the progress of ALS varies significantly from patient to patient, statements about the prognosis and life expectancy are hard to make.