Walsh & Hoyt: Shy-Drager Syndrome

Shy-Drager syndrome is a subtype of multiple system atrophy (MSA), one of the three idiopathic neurodegenerative syndromes (onset usually after age 50 years) that primarily affect the autonomic nervous system. The other two are pure autonomic failure, in which impairment of the autonomic nervous system (orthostasis, bladder dysfunction, sexual impotence) occurs without other neurologic features, and Parkinson disease, in which autonomic impairment occurs with an extrapyramidal movement disorder. In MSA, autonomic impairment occurs with an extrapyramidal movement disorder, a cerebellar movement disorder, or both. Patients with MSA are said to have Shy-Drager syndrome when their symptoms and signs are primarily those related to autonomic failure.