Multiple system atrophy (MSA) is a neurodegenerative disease that affects involuntary body functions such as blood pressure and heart rate as well as movement. It is similar to Parkinson's disease, with onset around 50 years of age and a rapidly advancing course of disease over 5 to 10 years. In the late stages, pneumonia and sudden death are common. MSA affects about 15,000 to 50,000 people in the US.
MSA was first named olivopontocerebellar atrophy more than one hundred years ago. Later, it was called “Shy-Drager syndrome with autonomic failure and features of parkinsonism.” The syndrome was defined as MSA in 1996 when distinctive glial cytoplasmic inclusions and large quantities of alpha-synuclein proteins were found in the brain tissue of patients with the disease. Those proteins, along with cell loss in physical areas of the brain connected to movement, clearly distinguished MSA from other diseases.
MSA has been known by many names over the years. In 2007, the American Academy of Neurology and the American Autonomic Society further classified MSA into two subtypes. MSA-P presents with predominant parkinsonism and in MSA-C cerebellar ataxia is the predominant symptom. Another term for MSA-P is striatonigral degeneration, and MSA-C is sometimes called sporadic olivopontocerebellar atrophy. When autonomic failure is the primary symptom, the older name Shy-Drager syndrome is sometimes used.
Clinical findings in patients with MSA include dysfunctions in the autonomic nervous system, urogenital system, and brain. This can result in a variety of symptoms throughout the body.
Orthostatic hypotension, or a drop in blood pressure when standing up from a sitting position, is a common feature of all forms of MSA. Urogenital dysfunction resulting in urinary incontinence or erectile dysfunction is also common.
If features of Parkinsonism are present, symptoms may include slow movements, or bradykinesia, postural instability, and tremors. Dysfunctions of the cerebellum may lead to an abnormal gait or other motor function problems.
Patients with the Parkinsonian type of MSA tend to present with difficulty bending their arms and legs, slow movements, tremors, and problems with posture and balance. They may also develop a resting tremor, which disappears when they move. MSA-P progresses relatively rapidly, and after several years, symptoms may become severe enough to require assistance with activities of daily living.
The cerebellar type of the disease will show an unsteady gait, poor balance, speech problems, abnormalities of vision, and difficulty swallowing or chewing. These patients may also develop a tremor, mostly an action tremor, occurring when the patient moves.
Other possible symptoms of the cerebellar type of the disease are: