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  • Paralysis agitans

  • 332.0 Paralysis agitans

  • G20 Parkinsonism (idiopathic) (primary)

  • 5E: Impaired Motor Function and Sensory Integrity Associated with Progressive Disorders of the Central Nervous System


  • Progressive degenerative disorder of the central nervous system
  • Death of dopamine-producing cells in the substantia nigra
  • Named after English MD, James Parkinson
  • Parkinsonian syndromes (4 types)
    • Primary or idiopathic, no known cause
    • Secondary or acquired
    • Hereditary parkinsonism
    • Parkinson plus syndrome or multiple system degeneration

Essentials of Diagnosis

  • Core features include a tetrad of hypo- or bradykinesia, resting tremor, postural instability, and rigidity
  • Some people have a rigidity-dominant presentation; others have a dyskinesia-dominant presentation (predominantly those with onset at a young age)
  • Pathophysiology

General Considerations

  • Positive diagnosis of PD is made with a successful levodopa (l-dopa) trial


  • Onset generally between 45 to 70 years of age
  • More common in men
  • Impacts all ethnic groups and socioeconomic classes
  • Most cases are idiopathic; genetic variants exist, but are rare

Signs and Symptoms

  • Tremor: usually asymmetrical
  • Gait disturbance, usually described as “festinating”
  • Postural instability
  • Stooped posture
  • Stiffness/rigidity: begins on one side
  • Slowness of movement
  • Dizziness
  • Freezing of movement
  • Bradykinesia or hypokinesia
  • Muscle ache
  • Loss of dexterity
  • Mask-like facial expression
  • Micrographia (small, cramped handwriting)
  • Depression
  • Neuropsychiatric problems
  • Speech disturbance: decreased volume and pitch, as well as motoric loss
  • Dementia in the later stages of the disease
  • Loss of smell
  • Constipation

Functional Implications

  • Progressive loss of
    • Balance reactions
    • Ambulation ability and safety
    • Respiratory capacity to support activity
    • Interaction with home and community environments

Possible Contributing Causes

  • Unknown
  • Drug-induced parkinsonism (DIP)

Differential Diagnoses

  • Hemiparkinson-hemiatrophy syndrome
  • Progressive supranuclear palsy (PSP)
  • Basal ganglia tumors
  • Vascular pathology
  • Multiple system atrophy (MSA)
  • Lewy body disease
  • Corticobasal ganglionic degeneration (CBGD)
  • Encephalitis
  • Pseudobulbar palsy
  • Binswanger’s disease
  • Normal-pressure hydrocephalus (NPH)
  • Multiple sclerosis (MS)

Laboratory Tests

  • Blood test to help rule out other disorders


  • Positron emission tomography (PET) scan
  • Magnetic resonance imaging (MRI) and Computed tomography (CT) usually normal

Diagnostic Procedures

  • Confirmation is made by a positive response to l-dopa trial in a patient with the tetrad of symptoms brady- or hypokinesia, resting tremor, postural changes and instability, cogwheel rigidity

  • PET scan would demonstrate decreased activity in the basal ganglia


  • Sinemet®
  • Ropinirole
  • Symmetrel®
  • Cogentin®
  • Entacapone
  • Rasagiline
  • Selegiline

  • To neurologist for imaging; disease management
  • To neurosurgeon for deep brain stimulation
  • To the National Parkinson Foundation for support


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