Updated on 06/07/2022
Syndromes that cause atypical parkinsonism are progressive degenerative diseases that begin with some signs and symptoms of Parkinson's disease. They generally do not respond to the levodopa treatment used in Parkinson's disease. Each of them is a disease that affects different brain regions and has its own findings. Differentiating from Parkinson's disease can be difficult because the symptoms are similar. Diseases causing atypical parkinsonism are as follows;
1. Progressive Supranuclear Palsy (PSP)
2. Multiple System Atrophy (MSA)
3. Corticobasal Ganglionic Degeneration (CBGD)
4. Lewy Body Dementia (LDB)
5. Vascular parkinsonism
6. Drug-induced parkinsonism
Progressive supranuclear palsy (PSP) is a degenerative disease with progressive limitation of gaze, gait disturbance and instability, slurring of speech, dysphagia, rigidity, and frontal-type cognitive disorders.
It is the most common cause of atypical parkinsonism. The average age of onset is 65. It is not seen before the age of forty.
Many different forms of PSP have been described. The most common forms are Richardson syndrome and PSP-parkinsonism.
The most common form of onset of Richardson syndrome is gait disturbance leading to falls. The fall is often backwards. Gaze paresis is the hallmark of PSP, but it may appear later. As the facial features become prominent, the expression of patients with PSP may seem surprised or worried. Speech slurring, dysphagia, stiffness, frontal cognitive disorders and sleep disturbances are other common findings.
PSP-parkinsonism is characterized by an asymmetrical onset in the arm or leg and an initial mild response to Parkinson's treatment. Therefore, it can be confused with idiopathic PD.
The diagnosis of PSP is a clinical diagnosis. There is no diagnostic laboratory or imaging method. Differential diagnosis includes other atypical Parkinsonian diseases.
Multisystem atrophy (MSA) begins with parkinsonism and accompanying prominent autonomic nervous system findings. The two most markedly affected autonomic systems are urinary and blood pressure control. Urgent urge to urinate, inability to urinate or incontinence may occur. Dizziness may occur due to the decrease in blood pressure by standing up, which we call orthostatic hypotension. These disorders can also occur in Parkinson's disease, but occur later in the disease. In MSA, these findings are early and more severe. Another clinical type of MSA causes dysfunction and imbalance in the cerebellum.
MSA is initially very similar to idiopathic Parkinson's disease and may even respond to treatment with levodopa. Other clues to suspect that the clinical diagnosis is not Parkinson's are the rapid progression of the disease, very prominent forward bending of the body and head, and early deterioration of voice and swallowing.
Corticobasal ganglionic degeneration (CBGD) begins with parkinsonism. In its classic form, the findings are very asymmetrical, with dystonic contractions or myoclonia (short and rapid beats) on one half of the body, usually one arm. Apraxia (muscle weakness, sensory and balance disorders, inability to perform a learned and previously performed movement without comprehension and concentration disorders) is seen on the most affected side. There are other clinical types of CBGD where speech and behavioral disorders are at the forefront. In its differential diagnosis, PSP, frontotemporal dementia and Alzheimer's disease are also included in addition to Parkinson's disease.
Lewy body dementia (LBD) is a neurodegenerative disease that causes forgetfulness and visual hallucinations. LBD can also start in the form of Parkinson's disease. However, the presence of dementia is the most important distinguishing feature. Dementia is also seen in Parkinson's disease, but it occurs in more advanced stages. Whereas, dementia and visual hallucinations appear earlier in LBD.
Vascular parkinsonism develops when the areas in the brain that control movement are affected by small vessel occlusions. The most important finding is gait disturbance. Medications that treat Parkinson's disease can sometimes be helpful. But the main treatment is to treat risk factors such as high blood pressure, sugar, high cholesterol and to increase physical activity in order to prevent stroke.
,There are many drugs that cause Parkinson's disease-like symptoms by blocking dopamine receptors in the brain. This is why it's so important to review the medications of a person with parkinsonism, since the first step of treatment is to discontinue this drug if at all possible.