Encephalitic changes

Introduction Encephalitis-like changes are seen in experimental examinations in sporadic encephalitis and are one of the pathological changes in cerebrospinal fluid. Also known as sporadic viral encephalitis, non-specific encephalitis and atypical encephalitis. It is one of the common syndromes of the nervous system, mainly including two kinds of diseases, such as sporadic viral encephalitis with pathogens and allergic demyelinating encephalopathy after infection. Demyelinating encephalopathy may be caused by viral infection. The patient's immune function, which leads to demyelination of the brain's allergic reaction, is roughly the same as that of acute disseminated encephalomyelitis. However, it is difficult to distinguish clinically.

Cause

The pathogens of viral encephalitis include ECHO virus, herpes simplex virus and adenovirus. Demyelinating encephalopathy may be caused by a viral infection that impairs the patient's immune function, leading to a demyelination of the brain's allergic reaction, which is the same as that of acute disseminated encephalomyelitis.

an examination

Related inspection

Complement-binding assay lymphocytic choriomeningitis complement-binding assay passive hemagglutination assay Bruzinski levy against epidemic encephalitis virus IgM antibody

1. Blood: The total number of white blood cells in the surrounding blood is normal or slightly increased. The white blood cell classification is normal or the percentage of neutrophils is higher than normal. The erythrocyte sedimentation rate is normal or accelerated.

2, cerebrospinal fluid:

1 Viral encephalitis-like changes: increased white blood cell count, early neutrophils increased significantly, lymphocytes predominate after 1 to several days, and plasma cells and lymphocyte-like cells were also seen. The protein is normal or slightly elevated.

2 demyelinating encephalopathy-like changes: the number of white blood cells is normal or slightly increased, the percentage of lymphocytes is increased, and large lymphocytes, lymphocyte-like cells, plasma cells and activated monocytes are also seen. Neutrophils are rare. . Most of the protein is normal. The cerebrospinal fluid changes of the above two lesions are relative and cannot provide a basis for diagnosis of viral encephalitis or demyelinating encephalopathy.

3, pathogen examination: cerebrospinal fluid or brain tissue (including cranial exploration or drilling and puncture brain tissue biopsy and autopsy) virus culture and isolation, serological examination, etc. have a diagnostic significance for viral encephalitis, but the virus separation time is more Long, the clinical diagnosis and treatment is often not very helpful.

4. EEG examination: Most patients have EEG abnormalities, but their changes are not specific. Common changes are diffuse abnormalities and focal activities on the background of diffuse abnormalities. Dynamic EEG observation during the course of the disease helps to determine the development and prognosis of the disease. Generally, with the development of the disease, the EEG changes are also aggravated; when the condition is improved, the EEG is also improved. For the sporadic encephalitis with a late diagnosis of psychosis, the EEG changes have certain differential diagnosis significance. .

5, radiological examination: conventional cranial radiology examination for the diagnosis of sporadic encephalitis is of no value. Head CT sometimes shows multiple scattered softening foci in the cerebral hemisphere, which has certain significance for the exclusion of space-occupying lesions.

Differential diagnosis

Encephalitis-like changes can often be divided into the following five types, which need to be correctly identified.

1. Mental disorder:

Emotional disorders (emotional instability, apathy, depression, euphoria, fear), mental retardation (reduction in understanding, memory, calculation, judgment, association, etc.), thinking disorder (silence, multi-word, speech disorder and delusion), behavior Obstacles (reduced movement, increased movement, impulsive, stupor state) are common. Mental disorders are often coexisting with disturbances of consciousness (, confusion, confusion). According to the patient's main mental symptoms can be divided into subtypes such as tension syndrome, schizophrenia, and dementia syndrome. During the progression of the disease, the manifestations of mental disorders often change, such as from psychomotor excitement to psychomotor depression. Generally, neurological signs such as hemiplegia and positive pyramidal tract signs can be detected during the course of the disease. Laboratory tests, such as cerebrospinal fluid, EEG, evoked potentials, CT and MRI, often have certain changes, and can be distinguished from non-organic psychosis such as affective psychosis and schizophrenia.

2, coma type:

Severe disturbance of consciousness occurs immediately after onset, such as varying degrees of coma or special disturbances of consciousness. The cerebral hemisphere lesions on both sides are strongly manifested as de-cortical state and blinking coma; when the upper brain stem is damaged, the brain is strong; when the basal ganglia is damaged, there may be tremor, dance-like involute, etc.; Hemiplegia or bilateral hemiplegia occurs when the body bundle is damaged. Patients may have pneumonia, urinary tract infections, etc. due to coma. The duration of coma varies, and mental disorders can occur during the process of improving consciousness. After waking up, certain neuropsychiatric sequelae may remain.

3, brain tumor type:

Mainly manifested as headache, vomiting, papilledema, spasm, partial sports seizures, etc., often accompanied by varying degrees of disturbance of consciousness. Although these symptoms are intended to be intracranial lesions, the onset is acute and the condition is rapidly aggravated. From the onset to the shortest symptom, only a few hours, most of them are within one month; intracranial pressure is sharply increased, and some patients can quickly There is a crisis of increased intracranial pressure; both head CT and MRI can be seen in diffuse cerebral edema and brain softening area, etc., which can help identify brain tumors, but the diagnosis sometimes depends on craniotomy or stereotactic drilling to make brain tissue. Biopsy.

4, epilepsy type:

The patient had no history of epilepsy before the illness. Common types of seizures are generalized tonic-clonic seizures and their continuous state, partial sexual seizures, complex partial seizures or mixed seizures. This type of patients with epilepsy as the main symptom after onset, some patients may have pre-existing symptoms such as fever, headache, dizziness, vomiting, active activity before seizure, followed by diffuse abnormalities, mild abnormalities in cerebrospinal fluid examination or Normal, CT and MRI can be seen diffuse cerebral edema, single or multiple focal lesions, etc., provide a basis for the diagnosis of symptomatic epilepsy; other manifestations of sporadic encephalitis can help the clinical diagnosis of this disease.

5, limited type:

Hemiplegia, unilateral sputum, cross sputum, quadriplegia, motor ataxia, extrapyramidal involuntary movement, cranial nerve damage were the main clinical manifestations, indicating that the lesion is located in a certain part of the brain, or in the cerebellum or brainstem. According to the onset of illness, disease development process, cerebrospinal fluid examination, CT or MRI, and the response to experimental treatment and identification of cerebrovascular disease, brain tumor, multiple sclerosis.

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