A 19-year-old man was evaluated because of progressive weakness of bilateral upper limbs. He noticed weakness of the weakness of the right hand six month prior to the visit followed by weakness of the left hand and twitching of the shoulder and pectoral muscles bilaterally. He did not have sensory symptoms or pain. Exam showed atrophy of hand interossi bilaterally, weakness in the left deltoid and pectoralis major( 4/5) , hyperreflexic ( +3) reflexes in upper and lower limbs, bilateral Hoffman, and sustained ankle clonus bilaterally. No fasciculations were noted. There was no weakness in the cranial muscles or lower limbs. Sensory exam, coordination and gait were also normal.
