Encephalitis is a rare condition in which the brain is inflamed causing neurologic changes. It is most often caused by a viral infection. If it is very mild, it may go unrecognized, and diagnosed as a viral illness with a headache but severe cases are serious and can be life threatening. If you think your child has encephalitis, contact the doctor right away. Treatment can decrease your child’s chances of long-term complications and help with recovery.
Bacteria can cause encephalitis, however the most common cause are viruses. These include viruses such as those that cause the stomach flu, chickenpox, fever blisters, or other childhood viral infections. In rare cases, encephalitis can also occur in children who have caught certain infections from an insect or animal bite or scratch. Mosquito- and tick-borne viruses can also cause encephalitis. These viruses can cause infections such as West Nile, La Crosse, St. Louis, western equine, and eastern equine encephalitis. Mosquitoes transfer the virus from animals, such as birds, chipmunks, or horses, to humans. Symptoms may appear from a few days to a couple of weeks after exposure. In people with weak immune system, there are many other causes for encephalitis including fungi and parasites.
In some cases, encephalitis may occur a few weeks after an infection. This happens because the immune system, while attacking the virus, also mistakenly attacks the brain tissue.
Despite advances in medicine, quite often the cause is undetermined.
In mild cases, symptoms are similar to the flu. These include:
In moderate to severe cases, symptoms may include:
Muscle weakness, loss of sensation in some parts of the body
Difficulty walking or using arms
Convulsions or seizures
Confusion, memory loss, personality changes
Speech, hearing, or vision problems
Nausea or vomiting
If the encephalitis is severe, your child will be admitted to the hospital and will likely see a pediatric neurologist for diagnosis and treatment. This is a doctor who specializes in neurologic problems in children. The doctor examines your child. He or she also asks about your child’s health history and symptoms. The following may also be done:
Spinal tap (also called a lumbar puncture) to check the health of the fluid around the brain and spinal cord. This fluid is called cerebrospinal fluid. During the test, the skin on the lower back is numbed with a local anesthetic. Then a needle is inserted into the spinal canal and a sample of the fluid is taken. The fluid is checked in a lab for signs of infection. The pressure of the fluid can also be measured.
MRI or CT scan to provide detailed pictures of the brain and check for swelling. Both tests are painless. Fluid called contrast dye may be used to make the brain easier to see. MRI is the preferred test but CT may be done if your child can't have an MRI or if MRI is not available in a timely manner. Medicine can be given to help your child stay calm and lie still during the tests.
Blood tests to check for the presence of specific viruses.
EEG (electroencephalogram) is a test to measure electrical activity of the brain.
A child with severe encephalitis will need to be in the hospital. He or she will be given fluids and medicines (antibiotics and antiviral medicines) through an IV (intravenous) line. If your child is having a seizures, he or she may be given anticonvulsant medicines. There are more unusual forms of encephalitis that may require treatment with intravenous steroids or immunoglobulin. Your child may be monitored in the hospital until symptoms improve. Overall treatment time will vary for each child based on the severity and cause of the brain inflammation. The doctor will speak with you about other forms of treatment if they are needed.
Children can recover completely, and most do. But in some cases, children may have ongoing neurologic problems such as trouble with learning, reasoning, speech, or movement. Regular follow-up with the doctor may be recommended depending on your child’s condition. Supportive care, such as speech, physical, or occupational therapy, may be prescribed to help your child, if needed.