Striatonigral Degeneration Clinical Presentation

Parkinsonism

The vast majority of patients with multiple system atrophy develop parkinsonism at some point, and the condition is often rapidly progressive.

Bradykinesia with rigidity, tremor, or postural instability is seen. Although the presentation can be asymmetrical (as is usually the case in Parkinson disease), symmetry of onset is particularly suggestive of multiple system atrophy with predominantly parkinsonian features (MSA-P). Absence of tremor is also suggestive of MSA-P (vs Parkinson disease). When present, tremor is usually irregular, postural, and may be associated with myoclonus. While resting tremor can be observed, it is uncommon.

Multiple system atrophy patients with parkinsonism may have a limited response to a trial of levodopa. However, a clear-cut response that is sustained beyond 2 years is unusual.

Dysautonomia

Some degree of autonomic failure is almost universal and may be the presenting symptom. Genitourinary complaints are common early in the disease. Symptoms include the following:

• Male erectile dysfunction
• Urinary symptoms - Frequency, urgency, incomplete bladder emptying, and incontinence
• Postural or postprandial hypotension - Syncopal events may occur secondary to cerebral hypoperfusion

Sleep disturbances

When possible, obtain information on the patient’s history from the patient’s sleeping partner. Sleep-related symptoms include the following:

• Rapid eye movement (REM) sleep behavior disorder
• Obstructive symptoms - Snoring, stridor, obstructive apneas
• Central symptoms - Central apneas, dysrhythmic breathing patterns
• Insomnia and/or excessive daytime sleepiness
• Restless legs syndrome

Additional findings

Additional findings in MSA-P include the following:

• Cerebellar findings - Gait or limb ataxia, cerebellar dysarthria
• Affective disorders - Depression, emotional lability
• Cognitive impairment - difficulty with visuospatial tasks, decreased verbal fluency, diminished executive function skills
• Dysphagia and/or dysphonia

Other etiologies

Features that suggest an etiology other than multiple system atrophy include the following:

• Family history - Multiple system atrophy is a sporadic neurodegenerative disease; however, Machado-Joseph disease (SCA-3) can present with similar clinical features and has a genetic basis
• Dementia - Cognitive deficits are sometimes present in multiple system atrophy, but dementia is not a predominant feature, unlike with diffuse Lewy body disease
• Presence of hallucinations (not secondary to medication) - This suggests Lewy body disease^[11]

Parkinsonism

Bradykinesia with rigidity, tremor, or postural instability occurs. Symmetrical onset is suggestive of multiple system atrophy (vs Parkinson disease). Absence of tremor is suggestive of MSA-P (vs Parkinson disease). When present, tremor is usually irregular, postural, and is associated with myoclonus. While resting tremor can be observed, it is uncommon.

Dysautonomia

Symptoms of dysautonomia include the following:

• Urinary retention, elevated postvoid residual
• Orthostatic hypotension - Systolic blood pressure reduction of more than 30 mm Hg or diastolic blood pressure reduction of more than 15 mm Hg within 3 minutes of standing from a previous period of recumbency of greater than 3 minutes

Cerebellar findings

Cerebellar findings include the following:

• Gait or limb ataxia
• Cerebellar dysarthria
• Cerebellar oculomotor dysfunction - This may include saccadic pursuit movements, gaze-evoked nystagmus, and ocular dysmetria

Cognitive impairment

Although dementia (as a predominant feature) is a criterion for exclusion of multiple system atrophy, studies suggest that some degree of cognitive impairment is common in multiple system atrophy, and particularly so in MSA-P.^[12] The extent of impairment varies significantly. When present, deficits include the following:

• Visuospatial and constructional dysfunction
• Impaired verbal fluency
• Dysexecutive syndrome

Additional findings

Additional findings in MSA-P include the following:

• Dysphagia and/or dysphonia
• Stridor - Initially, stridor occurs during sleep, but later in the course of the disease it may occur during wakefulness
• Corticospinal findings - Hyperreflexia or extensor plantar response is often present
• Raynaud phenomenon, or "cold hands sign" - Cold, dusky, violaceous hands with poor circulatory return after blanching pressure^[13]
• Affective disorders - Depression, emotional lability

Other etiologies

Features that suggest an etiology other than multiple system atrophy include the following:

• Classic pill-rolling tremor - Suggests Parkinson disease
• Significant slowing of vertical saccades or vertical supranuclear gaze palsy - A sign of progressive supranuclear palsy
• Dementia - Cognitive deficits are sometimes present in multiple system atrophy, but dementia is not a predominant feature
• Presence of hallucinations (not secondary to medication) - Suggests Lewy body disease^[11]