American Medical Association Family Medical Guide - American Medical Association [436]
Antiviral medications are prescribed for some types of viruses.
Treatment
Treatment of bacterial meningitis is started immediately. If you have bacterial meningitis, you will probably be hospitalized for 1 to 2 weeks. Your doctor will prescribe a pain reliever and fever-reducing medication, along with large doses of antibiotics and fluids given intravenously (through a vein).
If you have viral meningitis, you will probably recover completely in a few weeks. Rest, drink plenty of water, and take an over-the-counter medication such as acetaminophen or ibuprofen to relieve pain and reduce fever. Antibiotics are not effective against viral meningitis.
Encephalitis
Encephalitis is inflammation of the brain, usually caused by a virus. The most common and severe cases of encephalitis are caused by the herpes simplex virus and are called herpes simplex encephalitis. In many cases, encephalitis results from a generalized viral infection such as mononucleosis (see page 935). West Nile virus (see page 944), which is carried by mosquitoes and can be transmitted to people by mosquito bites, can cause encephalitis. In people who have an impaired immune system (such as people who have AIDS; see page 909), encephalitis may result from viruses such as the cytomegalovirus (see page 508) or the varicella-zoster virus; these organisms generally do not cause illness in healthy people.
Encephalitis can sometimes result from an infection with a bacterium such as the one that causes Lyme disease (see page 942), or another type of microorganism (a protozoan) that causes toxoplasmosis (see page 508).
Life-threatening encephalitis is not common in healthy people; most people recover with no problems. The risk of serious illness or death depends on a person’s age (the very young and the very old are more likely to have more severe cases of encephalitis), on his or her general health, and on the particular disease-causing organism. A small percentage of cases (usually those caused by the herpes simplex virus) result in permanent memory impairment or brain damage.
Symptoms
The symptoms of encephalitis can vary widely. In mild cases, symptoms may be limited to fever, headache, and fatigue. Encephalitis is usually accompanied by meningitis (see previous article), and a person may also have a stiff neck. In severe cases, especially if a person has herpes simplex encephalitis, brain function is affected more, causing confusion, odd behavior, irritability, or restlessness. A person may also have muscle weakness in the arms and legs, muscle spasms, loss of coordination and balance, speech or vision impairment, or seizures. The infection can sometimes lead to coma and death.
Diagnosis
If you have symptoms of encephalitis, your doctor will recommend that you have a CT scan (see page 112) or MRI (see page 113) of your brain, and an electroencephalogram (EEG; see page 687) to evaluate the electrical activity of your brain. A lumbar puncture (see previous page) is done to help identify the disease-causing organism. In rare cases, a biopsy of the brain is done to make a diagnosis. Blood tests may be repeated after several weeks to test for antibodies (infection-fighting proteins) to various microorganisms that can cause encephalitis.
Treatment
Life-threatening types of encephalitis (such as those caused by the herpes simplex virus) are treated with antiviral drugs such as acyclovir. In people who have a weakened immune system, an infection caused by the cytomegalovirus or the varicella-zoster virus may respond to treatment with antiviral drugs such as ganciclovir, foscarnet, or cidofovir.