Encephalitis means inflammation of brain , which is usually caused by a virus. It is a rare but a potentially fatal condition. When the brain becomes inflamed and irritated it increases its volume, the normal circulation of blood is impaired, leading to symptoms such as confusion, fever and severe headache. The disease comes in two forms: a primary and a more serious form and a secondary, easier form. Due to its gravity, most doctor visits are due to primary encephalitis. The most common cause of encephalitis is herpes simplex virus, the same virus that causes sores when cold and genital herpes. Sometimes this disease can be caused by viruses that cause mumps, rubella, measles, influenza and mononucleosis (Epstein-Barr virus). Another group of viruses called arboviruses can spread encephalitis mainly by mosquitoes and ticks bites. Only a small number of people stung by infected ticks or mosquitoes develop symptoms of encephalitis. Disease caused by arboviruses occurs usually in summer and early fall when mosquitoes bite people who spend more time outdoors. Although rare, infection with rabies virus can lead to encephalitis.
- Fever and headache are the symptoms of essential
- Lack of energy
- Dizziness, nausea and vomiting
- Changes in personality
- Memory Loss
- Confused Speaking
- Unusual behavior
Encephalitis itself is not contagious, but depending on the type of microbes, and infection can spread in several ways. A severe form of encephalitis can lead to coma or death. Severe symptoms such as seizures decrease the chances for a full recovery if, or if treatment is delayed. In case of acute encephalitis, it may take up to a week and full recovery may be spread over a period of several weeks, even months, depending on its stage of advancement.
Laboratory tests that can be used to diagnose encephalitis include:
- Analysis of spinal cord fluid (CSF): This is one of the most important diagnostic tests, samples are taken during a spinal puncture, the needle is inserted into the lower spine between the vertebrae and spinal fluid is examined for evidence of infection, such as increased number of leukocytes and proteins
- In case of encephalitis caused by herpes simplex virus, traces of viral genetic material can be found in the CSF. A viral culture cand be made to identify the virus that caused encephalitis (a small amount of cerebrospinal fluid is placed in a container which contains cells that grow the virus. It may take several weeks until viral culture results are ready)
- Magnetic Resonance Imaging (MRI) of the head can be used to detect specific areas of inflammation or bleeding in the brain caused by encephalitis. However, many patients with encephalitis have normal MRIs. Another imaging test, CT (computed tomography) of the face and head can be used to see these changes in the brain. CT uses X-rays to “photograph” the brain.
- Testing blood for finding antibodies can identify some causes of encephalitis, including viruses transmitted by mosquitoes and viruses that cause mononucleosis (Epstein-Barr virus), cytomegalovirus and toxoplasmosis.
- Electroencephalogram (EEG). An electroencephalogram (EEG) can help confirm a diagnosis of encephalitis. An EEG records the electrical activity of the brain with the help of electrodes mounted on the head and attached to a computer. In case of encephalitis, the EEG will show an increased or decreased abnormal electrical activity. However, EEG can not show whether abnormal electrical activity is caused by encephalitis.
- Brain biopsy may be used to find the cause encephalitis, especially if herpes simplex virus is suspected as the cause of encephalitis and the patient shows improved clinical condition after treatment with acyclovir (antiviral medication used to treat infections with herpes simplex virus). An MRI can guide specialists in determining the site of biopsy, if biopsy is needed. Using MRI to guide the biopsy needle, a small piece of brain tissue is extracted and examined to find the viral infection. Brain biopsy is rarely used, because blood tests and cerebrospinal fluid can provide an accurate diagnosis of encephalitis caused by herpes simplex virus.
Encephalitis treatment is performed in the intensive care unit of a hospital where the vital signs of the patient are closely monitored (blood pressure, heart rate, breathing and the body fluids). Treatment depends on the symptoms and specific cause of encephalitis, if the cause can be identified. Encephalitis caused by herpes simplex virus or varicella-zoster can be treated with acyclovir (antiviral medication), which is administered intravenously. Because early treatment increases the chances of recovery, it is important that therapy with acyclovir should be started as soon as encephalitis is suspected, even if we do not know the exact cause of the disease. With early treatment, 70% of herpes simplex encephalitis recover. Treatment has the greatest effect if given within 4 days after onset.
Call a physician as soon as possible if you consider encephalitis symptoms have installed such as severe headaches, fever and confusion, especially if accompanied by neck stiffness, nausea, vomiting and dizziness. Some doctors use valacyclovir for herpes simplex encephalitis, even though this medication has not been formally approved for the treatment of encephalitis.
Encephalitis caused by arboviruses, which are transmitted by mosquitoes and ticks, do not respond to acyclovir or other medications. Instead of trying to kill the virus, doctors treat the symptoms so the patient is comfortable and allow the body to heal itself. Mild fever can help the healing process and is usually not treated. Aspirin should not be administered to individuals younger than 20 years due to the risk of Reye syndrome. Seizures can be treated with anticonvulsant medications such as phenytoin (Dilantin) or phenobarbital. A ventilator (artificial breathing machine) and other supportive measures can be taken to help the patient who falls into a coma.