A degenerative disorder affecting upper MOTOR NEURONS in the brain and lower motor neurons in the brain stem and SPINAL CORD. Disease onset is usually after the age of 50 and the process is usually fatal within 3 to 6 years. Clinical manifestations include progressive weakness, atrophy, FASCICULATION, hyperreflexia, DYSARTHRIA, dysphagia, and eventual paralysis of respiratory function. Pathologic features include the replacement of motor neurons with fibrous ASTROCYTES and atrophy of anterior SPINAL NERVE ROOTS and corticospinal tracts. (From Adams et al., Principles of Neurology, 6th ed, pp1089-94)

Synonyms: Amyotrophic Lateral Sclerosis, Guam Form, Amyotrophic Lateral Sclerosis-Parkinsonism-Dementia Complex 1, Lou Gehrig's Disease, Guam Disease, ALS - Amyotrophic Lateral Sclerosis, Gehrig's Disease, Dementia With Amyotrophic Lateral Sclerosis, Lou-Gehrigs Disease, Amyotrophic Lateral Sclerosis Parkinsonism Dementia Complex 1, Gehrigs Disease, Disease, Guam, Amyotrophic Lateral Sclerosis, Parkinsonism Dementia Complex of Guam, ALS Amyotrophic Lateral Sclerosis, Amyotrophic Lateral Sclerosis, Sclerosis, Amyotrophic Lateral, Guam Form of Amyotrophic Lateral Sclerosis, Disease, Lou-Gehrigs, Amyotrophic Lateral Sclerosis With Dementia, Lou Gehrig Disease, Amyotrophic Lateral Sclerosis, Parkinsonism-Dementia Complex of Guam, Motor Neuron Disease, Amyotrophic Lateral Sclerosis, Charcot Disease, Gehrig Disease