ENCEPHALITIS

ENCEPHALIT - inflammatory disease of the brain of an infectious, infectious-allergic or allergic nature. Along with brain damage, the spinal cord (encephalomyelitis) and the meninges (meningoencephalitis) can be affected. Pathogens can be viruses, bacteria, rickettsia, fungi, protozoa, helminths.

Primary encephalitis is an independent disease that usually causes neurotropic viruses, mainly arboviruses, transmitted to humans when bitten by infected blood-sucking arthropods. These diseases are related to natural focal diseases, associated with certain landscape and climatic zones of arthropod habitat. Secondary encephalitis is more common in childhood infections - rubella, smallpox, measles, epidemic parotitis. Sometimes secondary encephalitis is a complication of the inflammatory process, penetrating wounds of the skull, can occur with allergies, after vaccination.

Infectious agents are more likely to get into the brain by the hematogenous way. Perhaps their penetration by contact (otogennym, rinogen, orbitogenic) with purulent inflammatory processes in the head and neck or head injuries. The most important feature of the pathological process is a rapid hyperergic reaction to a number of pathogenic effects, manifested by local or general edema of the brain. As a result of edema, brain displacement is possible, wedging into the large occipital foramen of the cerebellar tonsils with compression of the brain stem and the defeat of its vital structures. Edema of the brain is the most frequent direct cause of death of a patient with encephalitis.

Primary encephalitis (tick-borne, mosquito, lethargic, chorioencephalitis, etc.) begins sharply or subacute: signs of intoxication appear in the form of weakness, headache, chills, fever, etc., against which the general cerebral, meningeal and focal neurological symptoms develop. To cerebral symptoms include mental disorders, seizures, mental disorders, headache , vomiting , etc. Disorders of mental processes can be expressed by a violation of orientation in the environment, in time and in relation to one's own personality, psychomotor agitation. Perhaps the development of delusional syndromes, visual, auditory and other hallucinations. In a number of cases, sleep, memory, thinking, behavior change, etc. are noted. Meningeal symptoms include headache , vomiting , increased sensitivity to irritants, stiff neck muscles, symptoms of Kernig, Brudzinsky, and others.

The nature of focal neurological symptoms depends on the localization of the inflammatory process. This may be pareses or paralysis, local convulsions, sensitivity disorders, speech, vision, hearing, etc. The pathological process in the brain stem is manifested by the signs of damage to the cranial nerves nuclei: double vision (diplopia), ovulation of the upper eyelid (ptosis), strabismus, Disorders of articulation (dysarthria), swallowing (dysphagia). In this case, paresis of all limbs (tetraparesis), sharp decrease in muscle tone, pyramidal symptoms, respiratory disorders and cardiovascular function may be observed. The lesions of the cerebellum and extrapyramidal system are manifested by disorders of coordination of movements, gait, disturbances in muscle tone, trembling of limbs and other violent movements, nystagmus, etc.

The duration of the acute stage of encephalitis varies in different forms from several days to several months. The transition of the disease into a chronic stage is possible. There may be a decrease in memory, intelligence, personality changes, neuroendocrine disorders.

In secondary encephalitis, their common clinical sign is the rapid development of meningeal symptoms of cerebral edema, widespread vascular disorders with multiple hemorrhages, which cause the emergence of diffuse focal neurologic symptoms. Motor, cerebellar and other neurologic symptoms develop in an insult-like manner; The appearance of paralysis and coordination disorders are often preceded by convulsions in the limbs. Various hyperkinesis, nystagmus, blindness (due to optic neuritis) are developing early. Secondary encephalitis is severe and characterized by such consequences as various defects in the motor sphere (paralysis, paresis), epileptic seizures, hydrocephalus , decreased intelligence, etc.

The diagnosis is made on the basis of the clinical picture, the history of the disease (including the epidemiological) and the results of laboratory studies. If suspected of encephalitis, a spinal puncture is indicated. The study of cerebrospinal fluid makes it possible to detect an increase in its pressure, an increase in the number of cells (lymphocytes or, more rarely, neutrophils), protein, etc. Microbiological and serological tests of the patient's blood and cerebrospinal fluid in many cases make it possible to isolate the causative agent of the growth of the corresponding antibodies in dynamics.

To clarify the diagnosis and differential diagnosis, it is advisable to study the fundus, conduct electroencephalography, echoencephalography, tomography, etc.

Patients are hospitalized in an infectious or neurological department, depending on the alleged etiology of encephalitis. With mosquito and tick-borne encephalitis in the early days of the disease, the introduction of a specific donor gamma globulin is shown. With all viral encephalitis in the acute stage, it is advisable to administer interferon and other antiviral drugs.

If suspicion of herpetic encephalitis should be started as quickly as possible with acyclovir, while trying to clarify the etiology of the disease. Acyclovir is prescribed intravenously drip in a dose of 10 mg / kg 3 times a day for 10-14 days. To reduce the risk of kidney failure, the drug is injected slowly (within 1 h). Complications: phlebitis at the injection site, renal failure , thrombocytopenia, dyspepsia , diarrhea. Occasionally, the introduction of the drug deepens the disturbance of consciousness, confusion, excitement , hallucinations , tremor, epileptic seizures. The drug has the maximum effect if the treatment starts early (before the development of coma). In severe cases, the patient should be placed in the intensive care unit, where supportive therapy, correction of intracranial hypertension, water-electrolyte disorders.

With purulent meningoencephalitis, antibiotics are used. Disintoxication (administration of solutions of glucose, haemodesis) and dehydration (lasix, mannitol) therapy, the appointment of ascorbic acid, trental, calcium preparations are shown. With pronounced signs of cerebral edema, corticosteroids are used. With progressive signs of respiratory failure, the patient needs to be transferred to an artificial lung ventilation. As means of symptomatic therapy, anticonvulsants, analgesics, etc. are prescribed. After the stabilization of vital functions, complex restorative treatment (massage, therapeutic gymnastics, drugs regulating microcirculation and metabolic processes in the brain, etc.) is performed.