Atypical Parkinsonian Syndromes

Overview and Symptoms

Patients with parkinsonism manifest some or all of these key motor symptoms:

• Muscle rigidity (which can feel like stiffness)
• Resting tremor (shakiness of hands, legs or jaw that comes out in rest)
• Bradykinesia (slowness of movements)
• Postural instability (imbalance, which can lead to falls)

These motor symptoms and common non-motor symptoms vary from patient to patient. The majority of patients with parkinsonism are eventually diagnosed with Parkinson's disease.

A small number of patients have types of parkinsonism that share some features with Parkinson's disease, but have additional symptoms and are more rapidly progressive. These symptoms may be due to a known or suspected cause such as tumors, strokes, inflammation of the brain, drugs, and toxins or they may indicate a rare neurodegenerative disorder.

These neurodegenerative disorders are together described as Parkinson's Plus syndrome or Atypical Parkinson's. The diagnosis is made by very close monitoring of changes in the neurological exam over time in combination with tests to rule out other causes. There is currently no single clinical test to confirm the diagnosis. A definite diagnosis can only be made by examining post-mortem brain tissue under a microscope.

The main types of neurodegenerative Atypical Parkinsonian Syndromes include:

Multiple System Atrophy (MSA)

MSA can manifest as parkinsonism (MSA-P) or as problems with coordination and balance (MSA-C; C stands for cerebellum, the part of the brain that finetunes movements). In both conditions, problems with regulation of blood pressure, control of bladder function and/or other so-called autonomic functions are common. When these problems occur in isolation, the disease is classified as Pure Autonomic Failure (PAF).

Progressive Supranuclear Palsy (PSP)

PSP can manifest as falls which are often unexpected and often lead to injury due to weakening of postural reflexes and balance. There are many other subtypes that present with changes in eye movement, language, fine motor skills or visual-spatial skills.

Corticobasal Syndrome (CBD)

Corticobasal ganglia degeneration can manifest as a loss in dexterity out of proportion to parkinsonian symptoms. It can overlap with subtypes of Progressive Supranuclear Palsy.