Encephalitis is a condition in which inflammation affects the parenchyma of the brain. Encephalitis can be a complication of common infections (e.g. tuberculosis, measles, rubella) and is very dangerous as it can lead to irreversible brain damage, and even death. What are the causes and types of encephalitis? How to recognize its symptoms? What is the treatment?

Encephalitisoccurs when inflammation reaches the parenchyma of the brain. Encephalitis is one of the inflammations of the central nervous system along with inflammation of the spinal cord and meninges.

Encephalitis can have various causes (including viruses, bacteria, drugs) and its course - it can be acute (and lead to death within a few hours), subacute and chronic (then the inflammation can last for years) . A common feature of all brain inflammations is high mortality.

Encephalitis - causes and types

Bacteria:

  • mycobacteria tuberculosis - tuberculous encephalitis
  • Borreliaburgdorferi- Lyme encephalitis (a complication after Lyme disease)

Viruses:

1. Enterovirus encephalitis (Coxsackie virus, ECHO, enterovirus 70 and 71)

2. Arbovirus encephalitis

  • Venezuelan (equine) encephalitis
  • St. Louis encephalitis - caused by a virus belonging to the Flaviviridae family, the same as the West Nile, Yellow Fever and Dengue viruses;
  • Japanese encephalitis - also caused by a virus belonging to the Flaviviridae family; Found in the Far East
  • Californian encephalitis - caused by a virus from the Buniavirus family;
  • tick-borne encephalitis - the disease is caused by a flavivirus belonging to the Flaviviridae family;

GOOD TO KNOW>>Vaccination against ticks prevents tick-borne encephalitis

  • progressive rubella encephalitis (usually absent in vaccinated people) - is caused by a slow-acting rubella virus;
  • Subacute sclerosing encephalitis is a late complication of slow measles infection. It occurs in about 1 in 1 million cases of measles, an average of 8-10 years after measles;

3. Rhabdovirus encephalitis (RNA viruses)

  • rabies (cerebral rabies)

4. Herpes virus encephalitis

  • herpetic encephalitis
  • cytomegalovirus infection
  • Epstein-Barr virus (EBV) infection
  • human herpes virus 6 (HHV-6) infection

Mushrooms

Fungi encephalitis is associated with fungi such asCryptococcus(fungus from the trzcococcus family),Mucor(fungus white),Candida albicans . Fungal encephalitis is common in immunocompromised people, lymphoma patients, or undergoing immunosuppressive therapy.

Protozoa

  • amoeba - amoebic meningitis and encephalitis
  • malaria germs - cerebral malaria
  • Toxoplasma gondii- toxoplasmosis meningitis
  • Teania saginata- cysticercosis of the brain

Post-vaccination encephalomyelitisand myelitis develops after vaccination (most often against rabies and smallpox).

Acute Disseminated Encephalomyelitis (ADEM) is an autoimmune demyelinating disease of the brain, i.e. the immune system attacks its own cells (in this case the brain cells).

In addition, encephalitis may occur after ingestion of certain medications (e.g. methotrexate) or poisoning with heavy metals (e.g. lead).

Also featured iscoma encephalitis(von Economo encephalitis), which is caused by an unknown pathogen.

Encephalitis - symptoms

  • fever
  • headaches (accompanied by nausea and vomiting as well as photophobia, hypersensitivity to auditory stimuli or skin hypersensitivity)
  • disturbances of consciousness (which cause disturbances in thinking and behavior)
  • symptoms of focal brain injury

Focal symptoms are disturbances in neurological functions related locally to specific areas of the brain. The most common focal symptoms are motor symptoms (weakness or disability in one or more limbs), sensory symptoms (disturbance / loss of sensation in one or more limbs, visual disturbances, double vision), speech disorders (e.g. difficulty understanding speech, words), cognitive disorders (memory impairment, spatio-temporal disorientation), balance disorders, and seizures. For example, coma encephalitis is characterized by sleep disorders andvigilance and double vision.

There are also symptoms typical of infection with a specific pathogen. For example, encephalitis, which was caused byBorrelia burgdorferi,will be accompanied by a characteristic erythema (with brightening in the middle) wandering.

Encephalitis - diagnosis

In addition to blood tests, neuroimaging tests are performed - electroencephalography (EEG), positron emission tomography (PET), transcranial magnetic stimulation (TMS) and functional magnetic resonance imaging (fMRI) are available.

Encephalitis - treatment

In the case of bacterial encephalitis, the patient is given antibiotics (usually penicillin).

Treatment of viral encephalitis is the administration of antiviral drugs. For example, in the case of herpetic encephalitis, acyclovir is administered.

In toxoplasmosis encephalitis, pyrimethamine and clindamycin (in the treatment of recent infection) as well as pyrimethamine and sulfadiazine (in chronic form) are used.

Bibliography: Fiszer U.,Meningitis and brain inflammation , "Doctor's guide" 2004, No. 9

Category:

Neurology