Description

Encephalitis (en-sef-uh-LIE-tis) is an inflammation of the brain. It can be caused by viral or bacterial infections, or by cells of the immune system mistakenly attacks the brain. Viruses that can lead to encephalitis can be transmitted by insects such as mosquitoes and ticks.

When the inflammation is caused by an infection in the brain, known as encephalitis infectious. And when it is caused by the immune system attacking the brain, is known as autoimmune encephalitis. Sometimes the cause is not known.

Encephalitis can sometimes lead to death. Immediate diagnosis and treatment is important, because it is difficult to predict how the encephalitis can affect each person.

Symptoms

Encephalitis can cause many different symptoms, including confusion, personality changes, seizures, or problems with movement. Encephalitis can also cause changes in vision or hearing.

The majority of people with encephalitis, infectious have symptoms similar to the flu, such as:

  • The pain of a headache.
  • Fever.
  • Pains in the muscles or joints.
  • Fatigue or weakness.

Typically, these are followed by more severe symptoms over a period of hours to days, such as:

  • Stiffness in the neck.
  • Confusion, agitation, or hallucinations.
  • Seizures.
  • The loss of feeling or being unable to move certain areas of the face or body.
  • The irregular movements.
  • The muscle weakness.
  • Problems with speech or hearing.
  • The loss of consciousness, including coma.

In infants and young children, symptoms can also include:

  • The bulging of the fontanelles of the skull of a baby.
  • Nausea and vomiting.
  • The stiffness affect the entire body.
  • Poor diet, or not wake up to eat.
  • Irritability.

In the autoimmune encephalitis, symptoms may develop more slowly over several weeks. Flu-like symptoms are less common, but sometimes it can be weeks before more serious symptoms start. The symptoms are different for every person, but it is common for people to have a combination of symptoms, including:

  • Changes in personality.
  • The loss of memory.
  • Difficulty understanding what is real and what is not, known as psychosis.
  • See or hear things that do not exist, known as hallucinations.
  • Seizures.
  • Changes in vision.
  • Sleep problems.
  • The muscle weakness.
  • Loss of sensitivity.
  • Difficulty walking.
  • The irregular movements.
  • Bladder and bowel symptoms.

When to see a doctor

Get medical attention immediately if you experience any of the more severe symptoms associated with encephalitis. A strong headache, the fever, and the change in the consciousness require urgent care.

Babies and young children with symptoms of encephalitis also needs urgent attention.

Causes

In approximately half of the patients, the exact cause of encephalitis is not known.

In those for which a cause is found, there are two main types of encephalitis:

  • Infectious encephalitis. This condition usually occurs when a virus infects the brain. The infection can affect an area, or be widespread. Viruses are the most common cause of encephalitis, infectious, including some that can be transmitted by mosquitoes or ticks. Very rarely, encephalitis can be caused by bacteria, fungi, or parasites.
  • Autoimmune encephalitis. This condition occurs when your own immune cells mistakenly attack the brain, or do that antibodies directed to proteins and receptors in the brain. The exact reason why this happens is not fully understood. Sometimes autoimmune encephalitis can be triggered by cancer or benign tumor, known as paraneoplastic syndromes of the nervous system. Other types of autoimmune encephalitis as acute disseminated encephalomyelitis (ADEM) can be triggered by an infection in the body. This is known as post-infectious autoimmune encephalitis. In many cases, non-activation of the immune response was found.

Common viral causes

The virus that can cause encephalitis include:

  • Herpes simplex virus (HSV). Both HSV type 1 and HSV type 2 can cause encephalitis. HSV type 1 causes cold sores and fever blisters around the mouth, and HSV type 2 causes genital herpes. Encephalitis caused by HSV type 1 is rare, but can result in significant brain damage or death.
  • Other herpes viruses. These include the Epstein-Barr virus, which commonly causes infectious mononucleosis and the varicella-zoster virus, which commonly causes chickenpox and herpes zoster.
  • The enteroviruses. These viruses include poliovirus and coxsackie virus, which usually causes an illness with symptoms similar to the flu, inflammation of the eyes, and abdominal pain.
  • The viruses transmitted by mosquitoes. These viruses can cause infections such as West Nile virus, La Crosse, St. Louis, western equine, and eastern equine encephalitis. The symptoms of an infection may appear within a few days to a few weeks after exposure to a virus transmitted by mosquitoes.
  • Tick-borne viruses. The Powassan virus is carried by ticks and causes of encephalitis in the midwestern united States. The symptoms usually appear about a week after the bite of an infected tick.
  • The rabies virus. Infection with the rabies virus, which is usually transmitted by a bite from an infected animal, causes a rapid progression to encephalitis, once symptoms begin. Rabies is a rare cause of encephalitis in the united States.

Risk factors

Any person can develop encephalitis. Factors that may increase the risk include:

  • Age. Some types of encephalitis are more common or more serious in certain age groups. In general, young children and older adults are at increased risk of most types of viral encephalitis. In the same way, some forms of autoimmune encephalitis are more common in children and young adults, while others are more common in older adults.
  • Weakened immune system. People who have HIV/AIDS, take immunosuppressant medication or have another condition that causes a weakening of the immune system are at greater risk of encephalitis.
  • Geographical regions. Tick or mosquito viruses are common in certain geographic regions.
  • The season of the year. The mosquito-and tick-borne diseases tend to be more common in the summer in many areas of the united States.
  • Autoimmune disease. People who already have an autoimmune disease you may be more prone to develop autoimmune encephalitis.
  • The habit of smoking. Smoking increases the chances of developing lung cancer, which in turn increases the risk of developing paraneoplastic syndromes including encephalitis.

Complications

The complications of encephalitis vary, depending on factors such as:

  • Of his age.
  • The cause of your infection.
  • The severity of their initial illness.
  • The time of onset of the disease to treatment.

People with relatively mild disease usually recover within a few weeks without long-term complications.

The complications of a serious illness

The inflammation can damage the brain, possibly resulting in coma or death.

Other complications can last for months or can be permanent. Complications can vary widely and may include:

  • The tiredness that does not go away.
  • Weakness or lack of muscle coordination.
  • Changes in personality.
  • Memory problems.
  • Hearing, or vision changes.
  • Problems with speech.

Prevention

The best way to prevent viral encephalitis is to take precautions to avoid exposure to the virus that can cause disease. Try:

  • Practice good hygiene. Wash your hands often and thoroughly with soap and water, especially after using the toilet and before and after meals.
  • Do not share utensils. Do not share dishes and drinks.
  • Teaching your children good habits. Make sure that you practice good hygiene and avoid sharing utensils in the home and the school.
  • Get the shots. Keep your own and your children's vaccines current. Before you travel, talk to your healthcare provider about the vaccines recommended for the different destinations.

Protection against mosquitoes and ticks

To minimize your exposure to mosquitoes and ticks:

  • Dress to protect yourself. Wear long-sleeved shirts and long pants outdoors. This is especially important if you are outside between dusk and dawn, when mosquitoes are most active. It is also important when you're in a wooded area with tall grasses and bushes, where ticks are most common.
  • Apply mosquito repellent. Chemicals such as DEET can be applied to both skin and clothing. To apply the repellent on your face, spray it on your hands and then wipe it on her face. If you use sunscreen and repellent, apply sunscreen first.
  • The use of insecticides. The Environmental Protection Agency, it is recommended to use products that contain permethrin, which repels and kills ticks and mosquitoes. These products can be applied on clothing, tents and other outdoor gear. Permethrin should not be applied to the skin.
  • Avoid the mosquitoes. Stay away from places where mosquitoes are the most common. If possible, do not do outdoor activities from dusk to dawn, when mosquitoes are most active. Repair broken windows and screens.
  • Get rid of the sources of water outside your home. Eliminate standing water in your yard where mosquitoes lay their eggs. Common locations include pots or other containers, lawn and garden, flat roofs, old tires, and clogged gutters.
  • Search for outdoor signs of viral disease. If you note sick or dying birds or animals, report your observations to your local health department.

Protection for young children

Insect repellents are not recommended for use in infants under 2 months of age. In contrast, the cover of an infant carrier or stroller with a mosquito net.

For older infants and children, repellents, with a 10% to 30% DEET are considered to be safe. Products that contain both DEET and sunscreen is not recommended for children. This is due to re-apply for sun protection can expose the child to an excess of DEET.

Tips for the use of mosquito repellent with children include:

  • Always help the children with the use of mosquito repellent.
  • Spray clothing and exposed skin.
  • Apply insect repellent on the outside to reduce the risk of inhaling the repellent.
  • Spray repellent on your hands and then apply it to the face of your child. Be careful around the eyes and the ears.
  • Do not use repellent on the hands of small children who may put their hands in their mouths.
  • Wash skin with soap and water when they get home.

Diagnosis

To diagnose encephalitis, a member of your health care team will perform a physical examination and take your medical history.

Your health care professional may recommend:

  • The brain images. Mri or ct imaging may reveal any inflammation of the brain or another condition that could be the cause of your symptoms, such as a tumor.
  • Spinal tap, also known as a lumbar puncture. A needle is inserted into the lower part of her back, removes a small amount of cerebrospinal fluid (CSF), the protective fluid that surrounds the brain and the spine. The changes in this fluid may point to infection and inflammation in the brain. Sometimes the CSF samples can be tested to identify the cause. This may include the analysis of the infection or the presence of antibodies associated with autoimmune encephalitis.
  • Other laboratory tests. The samples of blood, urine, or excretions of the back of the throat can be tested for the virus or other infectious agents.
  • Electroencephalogram (EEG). Electrodes attached to your scalp to record the electrical activity of the brain. Certain patterns point to the encephalitis.
  • Images of body. Sometimes, autoimmune encephalitis can be triggered by an immune response to a tumor in the body. The tumor can be benign or cancerous. Your health care professional may order imaging studies, such as ultrasound, mri, CT or PET-CT. These scans can look at your chest, abdomen or pelvis to check for these tumors. If the mass is found, a small part of it can be removed for study in a laboratory. This is known as biopsy.
  • The biopsy of the brain. Rarely, a small sample of brain tissue may be removed for the test. A brain biopsy is usually done only if the symptoms are getting worse, and the treatments are having no effect.

Treatment

The treatment for mild encephalitis usually consists of:

  • The bed rest.
  • Plenty of fluids.
  • Anti-inflammatory medications such as acetaminophen (Tylenol, others), ibuprofen (Advil, Motrin IB, others) and naproxen sodium (Aleve) — to relieve headaches and fevers.

Antiviral medications

Encephalitis caused by certain viruses generally require antiviral treatment.

Antiviral medications are commonly used to treat encephalitis include:

  • Acyclovir (Zovirax, Sitavig).
  • Ganciclovir.
  • Foscarnet (Foscavir).

Some viruses, such as the insect transmission of viruses, it does not respond to these treatments. But due to the specific virus can not be identified immediately, or at all, can be treated with acyclovir. Acyclovir may be effective against HSV, which can result in serious complications when not treated quickly.

Antiviral medications are generally well tolerated. Rarely, the side effects can include damage to the kidneys.

Autoimmune encephalitis

If the tests show an autoimmune response that causes encephalitis, then the drugs that target the immune system, known as immunomodulatory drugs or other treatments can be initiated. These may include:

  • Intravenous or oral corticosteroids.
  • Intravenous immunoglobulin.
  • The Plasma exchange.

Some people with autoimmune encephalitis need of long-term treatment with immunosuppressive drugs. These may include azathioprine (Imuran, Azasan), mycophenolate mofetil (CellCept), rituximab (Rituxan), or tocilizumab (Actemra).

Autoimmune encephalitis caused by tumors may require the treatment of tumors. This may include surgery, radiation, chemotherapy, or a combination of treatments.

Supportive care

People who are hospitalized with severe encephalitis may be that you need:

  • Respiratory support, as well as careful monitoring of breathing and heart function.
  • Intravenous fluids to ensure adequate hydration and the levels of essential minerals.
  • Anti-inflammatory medications, such as corticosteroids, to reduce swelling and pressure inside the skull.
  • Anti-seizure medications to stop or prevent seizures.

Monitoring of therapy

If you experience complications of encephalitis, you might need additional therapy, such as:

  • The brain of rehabilitation to improve cognition and memory.
  • Physical therapy to improve strength, flexibility, balance, motor coordination, and mobility.
  • Occupational therapy to develop life skills and adaptive use of products that help with activities of daily living.
  • Speech therapy to relearn the muscle control and coordination to produce speech.
  • Psychotherapy to learn coping strategies and the new behavioral skills to improve the mood disorders of address or changes in personality.

Preparing for your appointment

Severity of the disease associated with encephalitis is usually severe and relatively sudden, and look for emergency medical attention. Your health care team is likely to include specialists in infectious diseases and in the nervous system and the brain, known as neurologists.

Questions for your doctor

You may need to answer these questions, or answer them in the name of your child or of another person with a serious illness:

  • When did the symptoms begin?
  • Have you recently started taking any new medication? If so, what is the medicine?
  • You've been bitten by a mosquito or tick during the last few weeks?
  • Have you traveled recently? Where?
  • Have you recently had a cold, the flu, or another disease?
  • Are up to date with their vaccinations? When was the last?
  • Have you had any exposure to wild animals or toxins known recently?
  • Have you had unprotected sex with a new or long-term sexual partner?
  • Do you have a problem or take any of the medications that result in a weakened immune system?
  • Do you have an autoimmune condition or make autoimmune conditions in the family?
Symptoms and treatment of Encephalitis