Meningitis is an infection of the meninges, the membranes that protect the spinal cord and the brain. When the meninges become infected, they start to swell, putting pressure on the spinal cord or brain and causing potentially life-threatening complications. Meningitis is called an acute condition because symptoms strike quickly and suddenly.
Although meningitis is most often caused by viruses, bacterial meningitis is more serious. The bacteria that cause bacterial meningitis are just about everywhere—they even live inside your respiratory tract. But they don't always make you sick. Experts don't always know why bacterial meningitis occurs. Some people get it when their immune system is down or they've recently been sick. Suffering a head injury may also increase your bacterial meningitis risk.
It's important to know what's causing your meningitis. Even though all types affect the same area of the body, they can have different outcomes and require different treatments.
Facts about bacterial meningitis
Although viral meningitis isn't usually serious, bacterial meningitis can lead to significant brain damage. Swelling of the meninges can result in paralysis or a debilitating stroke. In some cases, bacterial meningitis is fatal.
Bacterial meningitis can be caused by many different types of bacteria, including Streptococcus pneumoniae, Neisseria meningitides, and Haemophilus influenzae, and vaccines are available that target many of them. Children now routinely get a meningitis vaccine around ages 11 to 12, followed by a booster vaccine at age 16. Bacterial meningitis is usually more common in infants under 1 year of age and people ages 16 to 21. College students living in dorms or other close quarters are at increased risk, as are adults with certain medical problems, including those without a spleen.
The most common symptoms of bacterial meningitis are:
Painful, stiff neck with limited range of motion
Feeling confused or sleepy
Bruising easily all over the body
A rash on the skin
Experiencing a sensitivity to light
These are symptoms to look for in children:
Symptoms typically come on quickly, in as little as a couple of hours or up to a day or two. If you think you or your child may have bacterial meningitis, go to an emergency room right away.
To diagnose bacterial meningitis, a doctor will usually perform a spinal tap (also called a lumbar puncture) to take a sample of fluid from around the spinal cord. The fluid is then analyzed for bacteria. The doctor will also talk to you about your symptoms and perform a physical exam, as well as check your joints for flexibility.
Other tests may include:
Prompt treatment of bacterial meningitis is crucial—it can save your life. Once a doctor has confirmed a diagnosis of bacterial meningitis and identified the type of bacteria that's causing the infection, you'll start taking antibiotics to kill the bacteria.
Antibiotics are given intravenously, through a needle placed into a vein (usually in the arm or hand). They may also be given along with a corticosteroid to help alleviate inflammation and swelling. Treatment also includes plenty of fluids to ward off dehydration.
Vaccines are available to help prevent bacterial meningitis. Ask your health care provider if you are a good candidate for one of them. Also call your health care provider to talk about preventive strategies if you've been around someone who has bacterial meningitis, because it can be contagious.
Up to 10 percent of people with bacterial meningitis don't survive. Some who survive the illness may battle seizures, brain damage, hearing loss, and disability for the rest of their life. But many people with bacterial meningitis survive without any permanent complications, usually thanks to quick diagnosis and treatment.
Key points to remember
If you feel like you've got the flu with unusual stiffness in your neck—if, for instance, you can't touch your chin to your chest—it could be meningitis. It's a good idea to get any symptoms checked out and treated as soon as possible to help ward off potentially grave complications.