Encephalitis
Causes and symptoms of encephalitis
What is encephalitis?
Encephalitis is a brain damage leading to inflammation. Encephalitis is caused by infectious, infectious-allergic, allergic and toxic factors. There is primary (independent) and secondary encephalitis. The second type occurs against the background of various diseases (flu, toxoplasmosis, measles, osteomyelitis, etc.); the first type includes epidemic, mosquito, tick-borne, enteroviral and herpetic encephalitis.
When encephalitis affects the gray matter of the brain, it is called polyencephalitis; in case of damage to white matter - leukoencephalitis; panencephalitis is a lesion of white and gray matter.
Depending on the course of the disease, encephalitis is divided into acute, subacute and chronic.
Encephalitis causes
The most common cause of encephalitis are viruses - neuroinfections, sometimes encephalitis also occurs as complications of various infectious diseases.
The etiology of encephalitis depends on its type and form.
Infected insects (ticks, mosquitoes), Coxsackie viruses, herpes, flu or rabies viruses can become the cause of primary viral encephalitis. Microbial encephalitis is caused by syphilis and typhus. Secondary encephalitis can develop as a result of measles, smallpox, rubella, malaria, toxoplasmosis, or as a complication after vaccination (DPT, smallpox, rabies vaccine).
The virus enters the human body in various ways. When a mosquito or tick bites, it enters the organs and brain through the blood vessels. The virus is also transmitted by contact, alimentary and airborne droplets.
Encephalitis symptoms
Symptoms of encephalitis depend on many factors: the causative agent of the disease, its pathology, course and localization. However, there are symptoms common to all types of encephalitis.
Like most infectious diseases, encephalitis is accompanied by fever, disruption of the gastrointestinal tract and upper respiratory tract. The patient is worried about headaches, vomiting, epileptic seizures and fear of light are characteristic. With encephalitis, disturbances of consciousness occur: starting with lethargy and drowsiness, and ending with coma. Sometimes the disease causes psychomotor agitation (motor restlessness, fussiness, destructive actions) and psychosensory disorders (impaired perception of size, shape, location of objects).
Sometimes encephalitis resolves in asymptomatic, abortive, or fulminant forms. Asymptomatic forms occur with moderate headache, fever, and dizziness. The abortive form manifests itself with symptoms characteristic of acute respiratory infections or gastric infection. The most dangerous is the fulminant form of encephalitis. It lasts from several hours to a couple of days and ends with death. Patients have a high fever, severe headache, and they fall into a coma. Death usually occurs from acute heart failure.
Types of encephalitis
Economo's epidemic encephalitis (lethargic encephalitis A) occurs due to a virus transmitted by airborne droplets and by contact. This type of encephalitis is typical for all ages. The body temperature quickly rises to 39–40 ° C, the patient feels a severe headache, lethargy, pain in the joints, consciousness is disturbed. Also symptoms are prolonged sleep disorder (hypersomnia, insomnia), tachycardia, respiratory rhythm disturbance, sweating. Due to oculomotor disorder, strabismus, gaze paralysis, and diplopia develop. Mental disorders are often observed, the patient is delirious or in a state of euphoria.
Tick-borne encephalitis refers to the primary viral encephalitis of the spring-summer season. The virus is carried by an infected tick found in the taiga and forests. The virus enters the human body with a tick bite. The disease begins with severe headache, vomiting, fever, and photophobia. Seizures, epilepsy, and paralysis of the neck may occur.
Japanese encephalitis (encephalitis B) is carried by mosquitoes infected with the virus. People and birds can also carry the virus. The incubation period lasts from 3 to 27 days. The disease begins with severe fever (above 40 ° C), chills, nausea and vomiting, muscle weakness and pain. Consciousness is impaired, seizures are possible, twitching of the limbs, damage to the cranial nerves (bulbar paralysis). A lethal outcome is possible in 50% of cases of the disease, most often death occurs within one week.
Influenza (toxic-hemorrhagic) encephalitis occurs against the background of influenza. Symptoms include severe headache, nausea, dizziness, muscle pain, weight loss, and sleep disturbances. This inflammatory brain disease can lead to epileptic seizures, paralysis, or coma.
Measles encephalitis (encephalomyelitis) may appear 3-5 days after a measles rash. The general condition of the patient worsens, the temperature rises, weakness and drowsiness can go into hibernation (soporosis) or coma. Sometimes, on the contrary, patients are overly excited, delirious, they have epileptic seizures. The disease affects the cranial nerves, especially the optic and facial nerves, paralysis, chorea, ataxia, and transverse myelitis may occur.
Encephalitis with chickenpox and rubella appears on the second to eighth day of illness. The nervous system is affected, a person becomes lethargic, drowsy, epileptic seizures, paralysis of the extremities are observed, coordination of movements is impaired.
Herpetic encephalitis is caused by the herpes virus. It affects the cerebral cortex and white matter. Such a virus can persist in the body for a long time, so herpes encephalitis is a "slow" infection. The acute form of the disease is characterized by fever, headache, vomiting, impaired consciousness, and epileptic seizures. Due to damage to the nervous system, a person loses orientation in space and time, his movements are chaotic, aphasia and apraxia are observed.
Polyseasonal encephalitis is a composite group of encephalitis, the etiology of which has not been clarified. The disease is manifested by lesions of the facial, oculomotor and abducens nerves; epileptic seizures, paralysis, hyperkinesis are possible, impaired consciousness leads to stupor or coma.
Toxoplasmotic encephalitis in an acute state is quite rare and is characterized by an increase in temperature. Against the background of this type of encephalitis, pneumonia, myocarditis, pharyngitis, conjunctivitis and monocytosis develop.
Encephalitis treatment
If a patient is diagnosed with encephalitis, he should be hospitalized immediately. A person is placed in an infectious diseases or specialized neurological department and prescribed the strictest bed rest and constant observation.
Tick-borne and Japanese mosquito encephalitis at the initial stage is treated with donor gamma globulin, interferon and other antiviral drugs are administered. Antibiotics are used for purulent meningoencephalitis. Patients receive detoxification and dehydration therapy, ascorbic acid, trental, calcium preparations are prescribed. For cerebral edema, corticosteroids are used. Sometimes encephalitis leads to respiratory failure and patients are transferred to artificial ventilation. Also, with encephalitis, anti-convulsive drugs, analgesics are shown; massage and physiotherapy exercises are recommended.
Article author: Mochalov Pavel Alexandrovich | d. m. n. therapist
Education: Moscow Medical Institute. IM Sechenov, specialty - "General Medicine" in 1991, in 1993 "Occupational Diseases", in 1996 "Therapy".
