- Clinical science
Parkinson-plus syndromes (or atypical parkinsonism) are a group of neurodegenerative diseases that present with parkinsonism and a variety of additional features. Depending on the particular syndrome, a combination of basal ganglia, cerebral cortical, cerebellar, midbrain, and/or brainstem structures are affected. The prognosis is less favorable than in . Parkinson-plus syndromes should be considered if parkinsonism does not respond to levodopa treatment, if dementia progresses rapidly, or if gait instability occurs early in the course of the disease. In most cases, only symptomatic treatment is possible.
Parkinson-plus syndromes have a number of features that differentiate them from (PD):
- Poor response to levodopa
- Early involvement of the autonomic nervous system (orthostatic hypotension, impotence, incontinence, anhidrosis)
- Early onset of postural instability with frequent falls
- Visual hallucinations (usually a sign of Lewy-body disease)
- Signs of cerebellar involvement
- Pathological reflexes present (e.g., Babinski sign); enhanced proprioceptive reflexes
- Eating and swallowing disorders; pronounced dysarthria
- Supranuclear vertical gaze palsy
- Cerebral atrophy, particularly of the frontal lobe with relative sparing of the hippocampi
- Lewy bodies (alpha-synuclein-positive cytoplasmic inclusions) in glia cells, which cause myelin and glial dysfunction and subsequent neuronal degeneration
- Other neuropathological findings: Lewy neurites, amyloid plaques, neurofibrillary tangles
- Clinical presentation: The sequence of symptoms is more variable than in most other types of dementia.
- Prognosis: Median survival is approx. 10 years.
- Definition: Multiple system atrophy (MSA) is a rare, adult-onset, neurodegenerative disease characterized by neuronal degeneration in the substantia nigra.
- Pathology: Lewy bodies
- Etiology: unknown
- Motor abnormalities
- Autonomic dysfunction (e.g., orthostatic hypotension, urinary incontinence, erectile dysfunction)
- Cerebellar symptoms (e.g., ataxia, tremor, dysarthria)
- Additional symptoms
- Primarily based on clinical features (especially autonomic dysfunction, including urogenital symptoms)
- MRI: hot cross bun sign
- IBZM-SPECT imaging :
Pure autonomic failure (PAF)
- Disorder of the autonomous functions that is not associated with symptoms of the central nervous system
- In contrast to MSA, postganglionic lesions predominate in PAF.
- Mainly affects male patients between the ages of 40 and 70
- Clinical features: orthostatic dysregulation with life-threatening drops in blood pressure (esp. in situations involving blood redistribution, e.g., high temperatures, while standing up, or after a meal), fecal and urinary incontinence, disorder of thermoregulation due to anhidrosis, and/or erectile dysfunction. Neck pain is a common prodrome.
- Therapy: no causal therapy
- Clinical features
- Dementia (at any stage)
- Asymmetric motor abnormalities, often initially affecting only one limb
- Alien limb phenomenon: The patient perceives the affected limb as not belonging to him or her.
- Diagnosis: : asymmetric focal cortical atrophy and bilateral atrophy of the basal ganglia on MRI
|Differential diagnoses of Parkinson-plus syndromes|
|Multiple system atrophy (MSA)||Progressive supranuclear palsy (PSP)||Corticobasal degeneration (CBD)||Dementia with Lewy bodies (DLB)|
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