Definition

Meningitis (pronounced meh-nen-JI-tiss) is an inflammation of the meninges (pronounced meh-NIN-jeez). The meninges are the thin layers of tissue that cover the brain and the spinal cord. Meningitis is most commonly caused by infection (by bacteria, viruses, or fungi). It can also be caused by bleeding into the meninges, cancer (see cancer entry), diseases of the immune system, and other factors. The most dangerous forms of meningitis are those caused by bacteria. The disease is very serious and can be fatal.

Description

Any time a part of the body is infected, it is likely to become inflamed and swollen. These symptoms are especially serious in the brain. The brain is enclosed in the skull, a bony structure that cannot change size. If the brain swells, it pushes outward against the skull. Brain cells may become squeezed and begin to die. Brain cells are some of the only...