Bacterial meningitis is a serious infection of the layers of tissue covering the brain and spinal cord (meninges).
Bacterial meningitis in older infants and children usually results from bacteria carried in the respiratory system, and, in newborns, meningitis often results from a bacterial infection in the bloodstream (sepsis).
Older children and adolescents have a stiff neck with a fever, headache, and confusion, and newborns and young infants are usually irritable, stop eating, vomit, or have other symptoms.
The diagnosis is based on the results of a spinal tap (lumbar puncture) and blood and urine tests.
Antibiotics are given to treat the infection.
Meningitis is sometimes fatal, even after receiving appropriate treatment.
Vaccination can help prevent certain bacterial infections that cause meningitis.
For an overview of meningitis, see Introduction to Meningitis. Also see Viral Meningitis (viral meningitis is more common but, in general, less severe than bacterial meningitis).
Meningitis can occur at any age. Meningitis in older children is similar to meningitis in adolescents and adults (see Acute Bacterial Meningitis). However, meningitis in newborns (see also Bacterial Meningitis in Newborns) and infants is different.
Although meningitis can occur in all children, children at particular risk of meningitis include those with sickle cell disease and those lacking a spleen. Children with birth defects of the face and skull may have defects in the bones that allow bacteria access to the meninges. Children who have a weakened immune system, such as those with AIDS or those who have received chemotherapy, are more susceptible to meningitis.
(See also Overview of Bacterial Infections in Childhood.)
Causes of Meningitis in Children
Meningitis in newborns usually results from an infection of the bloodstream (sepsis). The infection is typically caused by bacteria acquired from the birth canal, most commonly group B streptococci, Escherichia coli, and Listeria monocytogenes.
Older infants and children usually develop infection through contact with respiratory secretions (such as saliva or mucus from the nose) containing the bacteria that cause meningitis. Bacteria that infect older infants and children include Streptococcus pneumoniae and Neisseria meningitidis. Haemophilus influenzae type b was the most common cause of meningitis, but widespread vaccination against that organism has now made it a rare cause. Current vaccines against Streptococcus pneumoniae (called pneumococcal conjugate vaccines) and Neisseria meningitidis (called meningococcal conjugate vaccines) also are making these organisms rare causes of childhood meningitis.
Symptoms of Meningitis in Children
Symptoms of meningitis vary by age. Once children develop symptoms involving their brain (such as abnormal drowsiness or confusion), meningitis can worsen very quickly. Some children who have bacterial meningitis become nearly or completely unconscious.
Newborns and children under 12 months of age
Newborns and children under 12 months of age rarely develop a stiff neck (a common symptom in older children) and are unable to communicate specific discomfort. In these younger children, important signs of illness that should alert parents to a possibly serious problem include
Unusual fussiness and irritability (particularly when they are held)
Abnormal drowsiness (lethargy)
Poor feeding
Temperature too high or too low
Vomiting
Rash
Seizures
About one third of newborns who have bacterial meningitis have seizures. And about 1 in 5 infants and young children who have bacterial meningitis have seizures. Occasionally, the nerves controlling some eye and facial movements may be damaged by the bacteria, causing an eye to turn inward or outward or the facial expression to become lopsided.
In about 33 to 50% of newborns with meningitis, increased pressure of the fluid around the brain may make the fontanelles (the soft spots between the skull bones) bulge or feel firm. These symptoms usually develop over at least 1 to 2 days, but some infants, particularly those between birth and 3 or 4 months of age, become ill very rapidly, progressing from health to near death in less than 24 hours.
Rarely, certain bacteria cause pockets of pus (abscesses) to form within the brain of infants with meningitis. As the abscesses grow, pressure on the brain increases (called intracranial pressure), resulting in vomiting, head enlargement, and bulging fontanelles.
Older children and adolescents
Older children and adolescents with meningitis typically have a few days of increasing
Fever
Headache
Confusion
Stiff neck
They may have had an upper respiratory tract infection before the meningitis. Seizures, pressure on the brain, and nerve damage may also occur.
Diagnosis of Meningitis in Children
Spinal tap
Blood and urine tests
Sometimes imaging tests
A doctor diagnoses bacterial meningitis by removing a sample of cerebrospinal fluid (fluid around the brain and spinal cord) obtained through a procedure called a spinal tap (lumbar puncture). The fluid is analyzed, and any bacteria in that sample are examined and grown (cultured) in a laboratory for identification. Sometimes the symptoms of bacterial meningitis are caused by other infections, such as inflammation of the brain (encephalitis) or another type of meningitis that is not caused by bacteria, so the sample is also examined to look for and rule out these other causes of the child's symptoms.
Sometimes a spinal tap cannot be done because the child has signs of increased pressure on the brain, a brain injury, or a bleeding disorder. In these instances, doctors look for bacteria in the bloodstream using blood cultures. These children will get a spinal tap as soon as it is safe to do it.
Other blood tests and urine tests (urinalysis and urine culture) are also done.
Ultrasonography and, more often, magnetic resonance imaging (MRI) or computed tomography (CT), are imaging tests that may be used to determine the degree of pressure on the brain and whether an abscess is present.
Treatment of Meningitis in Children
Antibiotics
Doctors give high doses of antibiotics by vein (intravenously) as soon as they suspect meningitis. Very sick children may receive antibiotics even before a spinal tap is done. When culture results from the spinal tap become available, doctors change the antibiotics, if needed, based on the type of bacteria causing the meningitis. The child's age also helps doctors determine which antibiotics to give.
Sometimes a second blood culture and spinal tap are done to determine whether the antibiotics are working.
Prognosis for Meningitis in Children
Even with timely, appropriate treatment, bacterial meningitis can be fatal in 5 to 20% of newborns and in 5 to 15% of older infants and children.
Bacterial meningitis can have long-term effects—20 to 50% of newborns develop chronic brain or nerve problems, such as an accumulation of extra fluid in the normal open spaces within the brain (hydrocephalus), hearing loss, and intellectual disability.
About 15 to 25% of older infants and children develop brain and nerve problems such as hearing loss, intellectual disability, and seizures.
Prevention of Meningitis in Children
Vaccinations can prevent many cases of bacterial meningitis. People who have been in contact with someone who has meningitis are often given antibiotics to help prevent infection (called chemoprophylaxis). Women can be screened for group B streptococcus while pregnant and, if positive, are given antibiotics at the time of delivery to prevent passing the bacteria to the newborn.
Vaccination
Health care professionals and parents can help prevent bacterial meningitis by ensuring that all infants receive the Haemophilus influenzae type b (Hib) conjugate vaccine, that all children up to 18 years of age receive the pneumococcal conjugate vaccine, and that older children and adolescents receive the meningococcal conjugate vaccine. Some infants and young children who are at high risk of Neisseria meningitidis infection also may be given the meningococcal vaccine.
Preventive antibiotics
When a person has meningitis caused by Neisseria meningitidis or Haemophilus influenzae, doctors usually give antibiotics to people who have been in close contact with the infected person to prevent other people from becoming sick. Close contacts are defined somewhat differently depending on which of these two bacteria has caused the meningitis, but they typically include
Members of the household (especially those under 2 years of age)
Workers at child care centers (especially workers in the infected child's classroom)
Anyone who has been directly exposed to the infected child's saliva (such as through kissing or sharing toothbrushes or utensils, or health care personnel doing certain procedures)
Exposed children who are not immunized or who are only partially immunized
Exposed children who have a weakened immune system
Preventive antibiotics are given to close contacts as soon as the infected child has been identified. Ideally, they are given within 24 hours.
