A 45-year-old man presents with weakness and fasciculations in his arms and legs. His cranial nerves are normal, but there is weakness of his left handgrip and right leg quadriceps with loss of muscle bulk. There are obvious fasciculations over the left forearm and right thigh. Tone is increased in the arms and legs and the reflexes are brisk. Which of the following is the most likely diagnosis?
The most common initial symptom of ALS is weakness and wasting of the extremities. The fasciculations can be a very prominent part of the disease. This is rare in other neurologic disorders.
amyotrophic lateral sclerosis (ALS)
myotonic muscular dystrophy
amyotonia congenita
tabes dorsalis
C.N.S.