Multiple system atrophy affects various organs simultaneously. The organs affected are related to autonomic nervous system and the condition is chronic and progressive.1 Although the exact cause of this condition remains unknown, the condition is characterized by the presence of α-synuclein aggregates primarily in oligodendroglia. Some studies also indicate genetics as a contributor, but conclusive evidence remains missing. MSA causes shrinkage of various important parts of the brain such as cerebellum and brainstem.
Classification/Types Of Multiple System Atrophy
The classification of multiple system atrophy is done on the basis of features of the disease and neuropathology. The classification of the condition is also done on the basis of symptoms and the organs and physiological functions affected. Classification is generally based on the general clinical domain. Following are the types of multiple system atrophy-
Multiple System Atrophy With Predominant Parkinsonism (MSA-P)- The condition is sometimes known as a parkinsonian variant of multiple system atrophy or striatonigral degeneration. In this condition the domination symptoms are extrapyramidal. Patients suffering from this condition have a rapid progression as compared to Parkinson’s patients and there is an early autonomic nervous dysfunction. Following are the symptoms experienced by the patient suffering from this type of Multiple System Atrophy, which are generally similar as seen in Parkinson’s disease-
Rigid Muscles– The muscle of the patient becomes rigid and the excess movement of the muscles causes pain and spasm.
Bradykinesia– The patient has a slow walking ability.2
Neuropsychiatric Features– Patients with MSA-P observers sleep disturbances. Other features include depression, apathy, Rapid eye movement, anxiety and sleep behavior disorder.
Although the exact cause of the development of MSA-P is not known the condition is characterized by the presence of aggregates of α-synuclein in various parts of the brain, especially in oligodendroglia. This is combined with the presence of the striatonigral pathway neurodegeneration.
Multiple System Atrophy With Cerebellar Features (MSA-C)- This type of multiple system atrophy is also known as sporadic olivopontocerebellar atrophy. The symptoms are predominantly related to cerebellar ataxia. The cause of this type is the aggregation of α-synuclein, especially in the oligodendroglia in combination with olivopontocerebellar structures neurodegeneration. The patient suffering from this type of MSA also shows some symptoms of MSA-P. Most of the symptoms are related to a lack of muscle coordination. The condition is characterized by the presence of the following symptoms-
- Loss of balance
- Impaired movement
- No control on the pitch and tone of the voice and the patient experiences slurred speech
- Visual disturbances such as lack of focus, blurred vision and double vision.
- Dysphagia means the patient experiences difficulty swallowing and difficulty chewing.
- Periodic limb movements in sleep
- Respiratory disturbances such as sleep apnea
- Sleep behavior disorder and rapid eye movement.
Multiple System Atrophy
The autonomic nervous system is part of the nervous system that is responsible for controlling the involuntary activities. Involuntary activities are those activities that are not in direct control such as blood pressure, digestion, temperature regulation, etc. When there is neurodegeneration of autonomic nervous system, the controlling ability of the brain takes a toll and it is visible in various physiological dysfunctions. This abnormal condition is termed as multiple system dystrophy. This condition is chronic and progressive and significantly impairs the quality of life. The general symptoms associated with the condition are dangerously low blood pressure on standing up, poor temperature regulation, bowel dysfunction causing constipation and urinary incontinence. The secretion of saliva, tears, and sweat reduces and the patient also experiences sexual dysfunction and emotional distress.
Multiple system atrophy is divided into two major types on the basis of part of the brain affected and the accompanying symptoms. The types of MSA are MSA-P, the Parkinson variant, and MSA-C, the Cerebellum variant. Symptoms of both the conditions may overlap but MSA-P has predominating Parkinson symptoms while MSA-C has the dominating symptoms of cerebellar ataxia. In MSA-P, the neurodegeneration of the striatonigral pathway occurs while in MSA-C, neurodegeneration of olivopontocerebellar structures is seen.