Etiology and classification of Parkinson's disease
The cause of Parkinson's disease is still unknown. At present, the recognized cause is nerve cell degeneration, and the main lesions are in substantia nigra and striatum. There is a nerve cell called substantia nigra. The number and function of substantia nigra cells gradually decrease, leading to the decrease of a substance called dopamine, which causes the above symptoms. According to the results of animal experiments and epidemiology, it is considered that Parkinson's disease is also related to heredity.
According to the etiology, the symptoms of paralysis agitans can be divided into two categories. One kind is called primary tremor paralysis, that is, there is no clear cause or the cause may be related to heredity. We call it Parkinson's disease or Parkinson's disease. The other is called secondary tremor paralysis, which is caused by some encephalitis and poisoning (such as carbon monoxide, manganese, cyanide, reserpine poisoning, phenothiazine and benzophthalein drugs and tricyclic antidepressant drugs poisoning, etc.). ), cerebrovascular disease, craniocerebral injury, brain tumor, etc. We also call it Parkinson's syndrome or Parkinson's syndrome and paralysis agitans syndrome.
Symptoms of Parkinson's disease
Parkinson's disease starts slowly and develops gradually, which means that it does not develop to a very serious degree at once, but a slow and gradual development process. The most prominent symptoms of patients are as follows:
1, dyskinesia. It can be summarized as: unable to exercise: it is difficult to start autonomous exercise. Motion reduction: spontaneous and automatic motion reduction, motion amplitude reduction. Slow action: random action is slow. The patient's movements are slow, and his random movements are reduced, especially when he starts to move, which is difficult, difficult and slow. When doing repetitive actions, the amplitude and speed gradually weaken. Some patients get smaller and smaller when writing, which is called "lowercase syndrome". Some people will have language barriers, their voices will become smaller and their vocal range will become narrower. Dysphagia and suffocation may occur when eating and drinking water. Some patients don't move for a few seconds to dozens of minutes after getting up. This situation is called "freezing attack".
2. Tremor. It is characterized by slow rhythmic tremor, which often starts from one finger and spreads to the whole upper limb, lower limb, lower jaw, lips and head. The typical tremor is static tremor, that is, the patient has involuntary tremor at rest. Mainly involving the upper limbs, hands shaking like rubbing the ball, and sometimes the lower limbs will tremble. Individual patients may involve mandible, lips, tongue and neck. 4 ~ 6 tremors per second, the amplitude is uncertain, and it will get worse when you are nervous. Many patients are accompanied by postural tremor 5 ~ 8 times per second. Some patients have no tremor, especially those over 70 years old.
3, rigidity. It is the stiffness of muscles that causes the muscles of limbs, neck and face to become stiff. When the limbs move, they have a sense of exertion, heaviness and powerlessness. Facial expressions may become stiff and blink less, resulting in a "mask face". The body bends forward, and it is particularly slow and difficult to walk, turn the neck and turn around. When walking, the coordinated swing of upper limbs disappears and the stride is shortened. Combined with flexion posture, the patient can walk forward with broken steps, which is called "panic gait".
With the development of the disease, it is difficult to dress, wash your face and brush your teeth. In addition, some patients may have autonomic nervous dysfunction, such as greasy face, sweating, salivation, difficulty in defecation and orthostatic hypotension, and may also have symptoms of depression and dementia. return
Diagnosis of Parkinson's disease
An epidemiological study of Parkinson's disease in China shows that the total number of people suffering from Parkinson's disease in China has reached 654.38+07200, and the prevalence rate of Parkinson's disease in people over 55 years old is nearly 654.38+0%. However, patients with Parkinson's disease confuse some early symptoms of Parkinson's disease with normal aging of body function, thus delaying the treatment opportunity.
1, diagnostic criteria of Parkinson's disease
(1) Clinical manifestations: Most patients with Parkinson's disease started after 60 years old, and occasionally patients in their twenties. The onset is mostly occult, developing slowly and getting worse gradually. The main manifestations are tremor (often the first symptom), myotonia, bradykinesia, abnormal posture and gait, and dyskinesia of mouth, pharynx and palate muscles.
(2) Auxiliary examination: The decrease of HVA (homovanillic acid) content in cerebrospinal fluid and urine can be detected by high performance liquid chromatography. Brain CT may have widened sulcus and enlarged ventricle.
(3) Exclude Parkinson's syndrome caused by encephalitis, cerebrovascular disease, poisoning and trauma, and differentiate it from hysteria, nervousness and senile tremor.
Diagnosis is mainly based on typical symptoms, and sometimes it is difficult to distinguish with the help of auxiliary examination. return
2. Differential diagnosis
It is mainly differentiated from Parkinson's syndrome, essential tremor and benign tremor.
(1) Parkinson's syndrome after encephalitis;
The so-called Parkinson's syndrome caused by lethargic encephalitis has not been reported in recent 70 years, so the Parkinson's syndrome caused by this encephalitis has disappeared. In recent years, it has been reported that patients with viral encephalitis may have Parkinson-like symptoms, but the disease has obvious infection symptoms, which may be accompanied by neurological damage symptoms such as cranial nerve paralysis, limb paralysis, convulsion and coma. Cerebrospinal fluid may have mild to moderate increase of cell number, increase of protein, decrease of sugar, etc. Parkinson-like symptoms are relieved after remission and can be distinguished from Parkinson's disease.
(2) Hepatolenticular degeneration:
Recessive hereditary disease, about 1/3, has a family history, and adolescents have symptoms such as increased limb muscle tension, tremor, facial masking, torsion spasm and so on. It is characterized by liver damage, corneal K-F ring and decreased serum ceruloplasmin. It can be distinguished from Parkinson's disease.
(3) Essential tremor:
This is a dominant genetic disease, characterized by involuntary tremor of the head, jaw and limbs. The frequency of tremor can be high or low, and the high frequency is very similar to hyperthyroidism. The low frequency is very similar to Parkinson's tremor. The disease has no decreased exercise, increased muscle tone and postural reflex disorder, and disappears after drinking. Propranolol is effective and can be distinguished from primary Parkinson's disease.
(4) Progressive supranuclear paralysis:
The disease is also common in middle-aged and elderly people, and its clinical symptoms may include extrapyramidal symptoms such as myotonia and tremor. However, this disease has prominent eyeball fixation disorder, myotonia is concentrated in the trunk, limb muscles are slightly involved and limb flexibility is maintained well, and neck hyperextension caused by increased tension of neck extensor muscles is obviously different from neck flexion of Parkinson's disease, which can be distinguished from Parkinson's disease.
(5)Shy_Drager syndrome:
Clinically, extrapyramidal symptoms often appear, but due to the prominent autonomic symptoms, such as syncope, orthostatic hypotension, sexual dysfunction, bladder dysfunction, etc., it can be distinguished from Parkinson's disease, and levodopa preparation is ineffective.
(6) Parkinson's syndrome induced by drugs:
Excessive use of antidepressants such as reserpine, chlorpromazine and haloperidol can cause extrapyramidal symptoms, which can be distinguished because of obvious medication history and remission after stopping taking drugs.
(7) Benign tremor:
Refers to physiological tremor (imperceptible to the naked eye) and functional tremor without brain organic lesions. Functional tremor includes: 1. Physiological tremor is enhanced (visible to the naked eye), mostly postural tremor, which is related to the enhanced adrenergic regulation response; Also found in some endocrine diseases, such as pheochromocytoma, hypoglycemia, hyperthyroidism; 2. Cocaine and alcoholism and the side effects of some drugs. Hysterical tremor is caused by many cardiac factors, and distraction can relieve tremor. 3. Others: nervousness and tremors when doing fine movements. Benign tremor has no characteristic manifestations of Parkinson's disease, such as myotonia, decreased movement and abnormal posture.