Causes, incidence, and risk factors
Acute bacterial meningitis can be caused by Gram-negative bacteria.
Meningococcal and H. influenzae meningitis are due to Gram-negative bacteria and are covered in detail in other articles. This article covers bacteria causing Gram-negative meningitis due to the following common causes:
Gram-negative meningitis is more common in infants than adults, but is of growing importance in adults, especially those with one or more risk factors. Risk factors in adults and children include:
Recent brain surgery
injury to the head
shuntplacement after brain surgery
Urinary tract abnormalities
Urinary tract infection
Weakened immune system
Feverand chills Mental status changes
- Nausea and vomiting
- Sensitivity to light (
- Severe headache
- Stiff neck (meningismus)
- Symptoms of a bladder, kidney, intestine, or lung infection
Other symptoms that can occur with this disease:
Bulging fontanellesin infants
Poor feeding or irritability in children
Unusual posture, with the head and neck arched backwards (
Signs and tests
The doctor or nurse will examine you. This will usually show:
Fast heart rate
Mental status changes
If the health care provider thinks you may have meningitis, a lumbar puncture (
Other tests that may be done include:
Blood culture Chest x-ray CT scan of the head
This list is not all-inclusive.
Antibiotics should be started as soon as possible. Ceftriaxone, ceftazidime, or cefepime are the most commonly used antibiotics for this type of meningitis. Other antibiotics may be used, depending on the type of bacteria.
If you have a spinal shunt, it may be removed.
The early treatment is started, the better the outcome.
Many people recover completely, but a large number of people have permanent brain damage or die from this type of meningitis. Young children and adults over age 50 have the highest risk of death. How well you do depends on:
How quickly the infection is treated
- Brain damage
- Buildup of fluid between the skull and brain (
- Hearing loss
Calling your health care provider
Call the local emergency number (such as 911) or go to an emergency room if you suspect meningitis in a young child who has the following symptoms:
Persistent unexplained fever
Call the local emergency number if you develop any of the serious symptoms listed above. Meningitis can quickly become a life-threatening illness.
Prompt treatment of related infections may reduce the risk of meningitis.