Any inflammation of the brain is referred to as encephalitis. The most common type, viral encephalitis, may be primary or secondary. Organisms that cause primary encephalitis include the polio, Coxsackie, and Type 1 herpes simplex viruses, as well as tick or mosquito borne arboviruses, which sometimes cause outbreaks of equine encephalitis in the summer. Secondary viral encephalitis can occur as a complication of a disease such as measles, mumps, rubella, or chickenpox. Such bacterial diseases as syphilis, streptococcus pneumonia, and tuberculosis can also be the cause of encephalitis. Sometimes meningitis, an inflammation of the membranes that cover the brain and spinal cord, also involves the brain itself.
Other Causes of Brain Inflammation
Brain inflammation may also be due to toxoplasmosis, a parasitic infection, or aspergillosis, a fungal infection. Lead poisoning can also cause an inflammation of the brain. People with AIDS, patients taking drugs that suppress the immune system, and others with lowered immunity are at a high risk of developing unusual brain infections.
Diagnostic Studies And Procedures
Mild viral encephalitis often goes undiagnosed, because the symptoms fever, headache, and malaise are short lived and attributed to flu or another minor illness. However, in its more severe form, encephalitis causes dizziness, confusion, vomiting, and a high fever. As the disease progresses, symptoms may include weakness or paralysis, impaired speech and hearing, delirium, excessive drowsiness, and coma. However such symptoms develop after a bout of a disease known to cause secondary encephalitis, a doctor should immediately suspect the disorder. But if the symptoms appear abruptly, other possibilities will be considered first. In addition to studies of blood and spinal fluid samples, tests may include a CT scan or MRI to rule out a brain abscess or tumor. After encephalitis is confirmed, further tests may be needed to identify the precise cause, so that treatment can be directed to eradicating it.
Mild encephalitis usually does not require treatment other than rest. If the the herpes simplex virus is causing the inflammation, intravenous treatment with acyclovir (Zovirax) or vidarabine (Vira A) is begun as soon as possible and continued for at least 10 days. When encephalitis is secondary to another infection, the underlying disease is treated. For example, antibiotics are used when the cause is a bacterial infection. Rest, replacement of fluids, and fever control are necessary to speed recovery. Adults can take either aspirin or acetaminophen to reduce a fever. Children can be given acetaminophen (important for preventing a seizure if temperature reaches 103°F), but not aspirin, because it increases the risk of Reye’s syndrome If excess fluid accumulates in the brain, mannitol, a diuretic, may be administered intravenously. Alternatively, the fluid may be removed by aspiration or by insertion of a shunt that carries it away from the brain. The long term outlook varies considerably and is not necessarily related to the severity of the disease. A person who is extremely ill may make a full recovery, while someone with a seemingly mild case may suffer permanent neurological damage.
The severe symptoms of encephalitis require prompt medical treatment. Alternative therapies should be considered only after checking with the primary care doctor.
Feverish patients may benefit from cool compresses and sponge baths with cool or tepid water.
To lower fever, some herbalists recommend 10 to 40 drops of boneset extract in a cup of warm water. Others advocate 1 to 3 capsules of feverfew a day, or 2 capsules of white willow bark every three hours. This last should not be given tea child, however, because it contains salicylate, an ingredient chemically similar to aspirin.
Services of physical and occupational therapists may be necessary, especially if the encephalitis results in permanent neurological problems. Some patients also may benefit from speech therapy if that function has been affected.
Stay in bed until symptoms abate. Eat light, nourishing meals and drink lots of fluids. During recovery, regularly do moderate exercise, such as walking, to regain your strength. To avoid encephalitis spread by mos quitoes or ticks, use an insect repellent when outdoors and make sure window screens are in good repair. Place some mosquito netting over cribs and beds if equine encephalitis occurs in your area. When traveling to or camping in mosquito infested areas, take along finemesh netting to sleep under.