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Multiple System Atrophy (MSA)


Phillip Low

, MD, College of Medicine, Mayo Clinic

Last full review/revision Apr 2020| Content last modified Apr 2020
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Multiple system atrophy is a relentlessly progressive neurodegenerative disorder causing pyramidal, cerebellar, and autonomic dysfunction. It includes 3 disorders previously thought to be distinct: olivopontocerebellar atrophy, striatonigral degeneration, and Shy-Drager syndrome. Symptoms include hypotension, urinary retention, constipation, ataxia, rigidity, and postural instability. Diagnosis is clinical. Treatment is symptomatic, with volume expansion, compression garments, and vasoconstrictor drugs.

Multiple system atrophy affects about twice as many men as women. Mean age at onset is about 53 years; after symptoms appear, patients live about 9 to 10 years.

There are 2 types of multiple system atrophy (MSA); types are based on the initial symptoms that predominate:

Both types involve autonomic nervous system dysfunction. Although multiple system atrophy begins as one type, symptoms of the other type eventually develop. After about 5 years, symptoms tend to be similar regardless of which disorder developed first.

Etiology of Multiple System Atrophy

Etiology of multiple system atrophy is unknown, but neuronal degeneration occurs in several areas of the brain; the area and amount damaged determine initial symptoms. A characteristic finding is cytoplasmic inclusion bodies containing alpha-synuclein within oligodendroglial cells.

Symptoms and Signs of Multiple System Atrophy

Initial symptoms of multiple system atrophy vary but include a combination of

  • Parkinsonism unresponsive to levodopa

  • Cerebellar abnormalities

  • Symptoms due to autonomic insufficiency

Parkinsonian symptoms

Parkinsonian symptoms Symptoms and Signs Secondary parkinsonism refers to a group of disorders that have features similar to those of Parkinson disease but have a different etiology. Atypical parkinsonism refers to a group of neurodegenerative... read more predominate in striatonigral degeneration. They include rigidity, bradykinesia, postural instability, and jerky postural tremor. High-pitched, quavering dysarthria is common.

In contrast to Parkinson disease, multiple system atrophy usually does not usually cause resting tremor and dyskinesia, and symptoms respond poorly and transiently to levodopa.

Cerebellar abnormalities

Cerebellar abnormalities predominate in olivopontocerebellar atrophy. They include ataxia, dysmetria, dysdiadochokinesia (difficulty performing rapidly alternating movements), poor coordination, and abnormal eye movements.

Autonomic symptoms

Other autonomic symptoms, which may occur early or late, include decreased sweating, difficulty breathing and swallowing, fecal incontinence Fecal Incontinence Fecal incontinence is involuntary defecation. (See also Evaluation of Anorectal Disorders.) Fecal incontinence can result from injuries or diseases of the spinal cord, congenital abnormalities... read more , and decreased tearing and salivation.

Patients may have nocturnal polyuria; contributing factors may include a circadian decrease in arginine vasopressin and treatments used to increase blood volume.

Diagnosis of Multiple System Atrophy

  • Clinical evaluation (autonomic insufficiency plus parkinsonism or cerebellar symptoms that respond poorly to levodopa)

  • MRI

  • Autonomic tests

Diagnosis of multiple system atrophy is suspected clinically, based on the combination of autonomic insufficiency and parkinsonism or cerebellar symptoms. Similar symptoms may result from Parkinson disease Parkinson Disease Parkinson disease is a slowly progressive, degenerative disorder characterized by resting tremor, stiffness (rigidity), slow and decreased movement (bradykinesia), and eventually gait and/or... read more , dementia with Lewy bodies Dementia with Lewy Bodies and Parkinson Disease Dementia Lewy body dementia includes clinically diagnosed dementia with Lewy bodies and Parkinson disease dementia. Dementia with Lewy bodies is chronic cognitive deterioration characterized by cellular... read more , pure autonomic failure Pure Autonomic Failure Pure autonomic failure results from neuronal loss in autonomic ganglia, causing orthostatic hypotension and other autonomic symptoms. (See also Overview of the Autonomic Nervous System.) Pure... read more , autonomic neuropathies Autonomic Neuropathies Autonomic neuropathies are peripheral nerve disorders with disproportionate involvement of autonomic fibers. (See also Overview of the Autonomic Nervous System.) The best known autonomic neuropathies... read more , progressive supranuclear palsy Progressive Supranuclear Palsy (PSP) Progressive supranuclear palsy is a rare, degenerative central nervous system disorder that progressively impairs voluntary eye movements and causes bradykinesia, muscular rigidity with progressive... read more , multiple cerebral infarcts, or drug-induced parkinsonism.

No diagnostic test is definitive, but some (eg, MRI, nuclear imaging with 123I-metaiodobenzylguanidine [MIBG], autonomic tests) help confirm clinical suspicion of multiple system atrophy—for example, if

  • MRI shows characteristic changes in the midbrain, pons, or cerebellum.

  • MIBG scans show intact innervation of the heart (because the lesion is preganglionic in MSA)

  • Autonomic tests indicate generalized autonomic failure.

Treatment of Multiple System Atrophy

  • Supportive care

There is no specific treatment for multiple system atrophy, but symptoms are managed as follows:

Patients require supportive therapy because the disorder is progressive and fatal.

Key Points

  • Multiple system atrophy can include parkinsonian symptoms, cerebellar abnormalities, and autonomic insufficiency in various degrees of severity.

  • Diagnose this disorder based on clinical, autonomic, and MRI findings, but consider Parkinson disease, dementia with Lewy bodies, pure autonomic failure, autonomic neuropathies, progressive supranuclear palsy, multiple cerebral infarcts, and drug-induced parkinsonism, which can all cause similar symptoms.

  • Use treatments specific for the symptoms present.

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