The Michael J. Fox Foundation has a new webpage on “Atypical Parkinsonism” as well as short descriptions of the four atypical parkinsonism disorders on their Fox Trial Finder site. Merging the two sources, I’ve copied below how the organization describes the four atypical parkinsonism disorders.
Robin
Atypical Parkinsonism
by Michael J. Fox Foundation
Atypical parkinsonism includes several conditions in which an individual experiences some of the motor signs and symptoms of Parkinson’s disease (PD), including tremor, slowness, rigidity (stiffness) and walking/balance problems, but does not have PD. [These] conditions tend to progress more rapidly than Parkinson’s and do not respond well to levodopa.
Atypical parkinsonism can sometimes be due to medications and may also be seen in other neurodegenerative and brain disorders. Some of the neurodegenerative diseases associated with atypical parkinsonism include:
* Corticobasal degeneration: CBD is a type of parkinsonism associated with very noticeable motor and cognitive (thinking) symptoms. People with CBD typically have prominent limb stiffness and dystonia (involuntary muscle contraction that causes an abnormal posture) and memory and/or thinking difficulties.
* Dementia with Lewy bodies: DLB, also called Lewy body dementia (LBD) also shares many symptoms of PD and Lewy bodies, but cognitive problems and dementia occur early in the disease process. DLB/LBD may also cause visual hallucinations (seeing things that aren’t there); unpredictable fluctuations in a person’s level of attention or alertness; and changes in mood, behavior and personality.
* Multiple system atrophy: MSA shares many symptoms with PD and also shows clumps of the alpha-synuclein protein (Lewy bodies). MSA affects the autonomic nervous system, which controls automatic, involuntary activities (like blood pressure, digestion and sexual function) and may cause fainting, severe constipation and/or issues with bladder control. Anterocollis (head dropping forward) and speech difficulties are commonly associated.
* Progressive supranuclear palsy: Walking and balance problems, which are also part of Parkinson’s, are particularly severe in PSP and people with this condition experience significant falls. Eye movement problems, which can cause blurred vision, and speech and swallowing disturbances are also prominent.
These neurodegenerative diseases, which cause damage or death of brain cells, are often referred to as “Parkinson’s plus” because they mimic PD but have extra associated features (the “plus”). They can be misdiagnosed as PD because there is no definite test that separates them and, early in the course, some people may get a short-term benefit from levodopa (the most commonly used medication to treat PD). A waning levodopa response, development of additional symptoms and more rapid progression of disease (as compared to Parkinson’s) may eventually differentiate these conditions from PD, although it can take years for these differences to emerge. As with PD, no disease-modifying therapy has been discovered for any of the neurodegenerative atypical parkinsonisms. Treatment is symptomatic and supportive.
Because of the similarities between PD and atypical parkinsonism, research into one can inform the science behind the other. Fox Trial Finder features studies recruiting individuals with atypical parkinsonism to uncover research breakthroughs that cross diagnostic lines.