brain, spinal cord, and nerve disorders
Multiple System Atrophy (MSA)
Introduction
Multiple system atrophy is a progressive, fatal disorder that causes symptoms resembling those of Parkinson disease (parkinsonism), loss of coordination, and malfunction of internal body processes (such as blood pressure and bladder control). The parts of the brain that control movements and many internal body processes degenerate. Symptoms include symptoms that resemble those of Parkinson disease, loss of coordination, low blood pressure when a person stands (orthostatic hypotension), problems with urination, and constipation. Doctors base the diagnosis on a person's response tolevodopa(used to treat Parkinson disease) and results of magnetic resonance imaging and tests of autonomic function. Simple measures and medications can help lessen symptoms, but the disorder is progressive and ultimately fatal. (See also Overview of the Autonomic Nervous System .) Multiple system atrophy usually begins when people are in their 50s. It affects men and women equally. There are two types of multiple system atrophy (MSA), based on which symptoms occur first: MSA-C is characterized by loss of coordination and difficulty maintaining balance, which indicates cerebellar dysfunction (indicated by the C). MSA-P is very similar to Parkinson disease (indicated by the P) except that the usual tremor often does not develop andlevodopaoften does not relieve symptoms. Both types involve autonomic nervous system dysfunction. Although multiple system atrophy begins as one of these types, symptoms of the other type eventually develop. After about 5 years, symptoms tend to be similar regardless of which disorder developed first. 