Meningitis

What causes meningitis?

Meningitis is usually caused by a bacterial or viral infection that invades the cerebral spinal fluid (CSF). Cerebral spinal fluid (CSF) is the fluid within the open spaces of the brain that protect and cushion the brain and spinal cord. A fungus or parasite may also cause meningitis. The severity of a child's symptoms and prognosis depend on the specific organism that is causing the meningitis. Meningitis can occur in infants, children, and adults. Some bacteria and viruses are more common in certain age groups than others, including the following:

Bacteria that can cause meningitis (bacterial meningitis)

In newborns and young babies, possible bacteria include the following:

• Group B streptococcus
• Escherichia coli (or E. coli)
• Listeria monocytogenes

In older babies and children, possible bacteria include the following:

• Streptococcus pneumoniae
• Neisseria meningitides (meningococcal meningitis)
• Haemophilus influenzae type b or H. influenzae

Other bacteria that may cause meningitis include the following:

• Syphilis
• Tuberculosis (TB)

Viruses that can cause meningitis (viral meningitis)

• Polioviruses
• Enteroviruses (such as coxsackieviruses and echoviruses)
• Mumps (paramyxovirus)
• Herpes simplex virus (HSV)

Other microorganisms that can cause meningitis

• Borrelia burgdorferi (Lyme disease)
• Fungi such as candida, aspergillus, or cryptococcus neoformans

Meningitis caused by a virus is more common and usually less severe. Bacterial meningitis is usually more severe and may produce long-term complications or death.

How is a meningitis infection transmitted?

The organisms that cause meningitis are usually spread by close contact with persons who may be carrying the infection, or by touching infected objects such as doorknobs, hard surfaces, or toys and then touching the nose, mouth, or eyes. The organisms may also be transmitted through respiratory secretions from a sneeze, close conversation, or by touching infected matter. The infection usually starts in the respiratory tract and then travels into the bloodstream where it can reach the brain and spinal cord. The organism may cause a cold, sinus infection, or ear infection (more common in children), and then travel through the sinuses into the brain and CSF, although this method of transmission is less common. A child may have no symptoms at all, but may carry the organism in his/her nose and throat.

What are the symptoms of meningitis?

The symptoms of meningitis vary depending on the organism that is causing the infection. However, each child may experience symptoms differently. Symptoms may include:

In infants (symptoms may be difficult to pinpoint)

• Irritability
• Fever
• Sleeping all the time
• Poor feeding
• High-pitched cry
• Arching back
• Cries when picked up or being held
• Inconsolable crying
• Bulging fontanelle (soft spot on an infant's head)
• Noticeably different temperament
• Seizures

In children older than one year

• Neck and/or back pain
• Headache
• Sleepiness
• Confusion
• Irritability
• Fever
• Refusing to eat
• Decreased level of consciousness
• Seizures
• Photophobia (sensitivity to light)
• Nausea and vomiting
• Neck stiffness

The symptoms of meningitis may surface several days after your child has had a cold and runny nose, or diarrhea and vomiting. The symptoms of meningitis may resemble other problems or medical conditions. Always consult your child's physician for a diagnosis.

How is meningitis diagnosed?

In addition to a complete medical history and physical examination, diagnostic procedures for meningitis may include:

• Lumbar puncture (spinal tap) - a special needle is placed into the lower back, into the spinal canal. This is the area around the spinal cord. The pressure in the spinal canal and brain can then be measured. A small amount of cerebral spinal fluid (CSF) can be removed and sent for testing to determine if there is an infection or other problems. CSF is the fluid that bathes your child's brain and spinal cord.
• Blood testing
• Computerized tomography scan (Also called a CT or CAT scan.) - a diagnostic imaging procedure that uses a combination of x-rays and computer technology to produce cross-sectional images (often called slices), both horizontally and vertically, of the body. A CT scan shows detailed images of any part of the body, including the bones, muscles, fat, and organs. CT scans are more detailed than general X-rays.

Treatment for meningitis

Specific treatment for meningitis will be determined by your child's physician based on:

• Your child's age, overall health, and medical history.
• Extent of the disease.
• The organism that is causing the infection.
• Your child's tolerance for specific medications, procedures, or therapies.
• Expectations for the course of the disease.
• Your opinion or preference.

Treatment may include:

Bacterial meningitis - Treatment for bacterial meningitis usually involves intravenous (IV) antibiotics. The earlier the treatment is initiated, the better your child's outcome. In a 2002 study, researchers found that administering a steroid in addition to antibiotics reduces the risk of death by as much as 50 percent in cases where the meningitis was caused by the Pneumococcus bacteria. The Pneumococcus bacteria account for 30 percent to 40 percent of bacterial meningitis. In addition, fewer patients suffered serious complications of their infection if treated with both the antibiotics and the steroid. The steroid, dexamethasone, when given with antibiotics, also reduces hearing loss in children associated with the infection. The steroid-antibiotics combination also appears effective for bacterial meningitis caused by the Meningococcus bacteria, but results were not conclusive.

Viral meningitis - Treatment for viral meningitis is usually supportive (aimed at relieving symptoms). With the exception of the herpes simplex virus, there are no specific medications to treat the organisms that cause viral meningitis. Most children with viral meningitis recover on their own without treatment.

Fungal meningitis - An intravenous anti-fungal medication may be administered to the child with fungal meningitis.
Tuberculous (TB) meningitis - A long course (one year) of medications is recommended for children who develop TB meningitis. The therapy usually involves treatment with several different medications for the first few months, followed by other medications.

What is supportive therapy for meningitis?

While your child is recovering from meningitis, other therapies may be initiated to improve healing and comfort, and provide relief from symptoms. These may include the following:

• Bed rest.
• Medications (to reduce fever and headache).
• Supplemental oxygen or mechanical ventilation (respirator) may be required if your child becomes very ill and has difficulty breathing.

Prevention of meningitis

Several vaccines are currently available to prevent some of the bacterial organisms that can cause meningitis, including the following:

• H. influenzae type b vaccine is given as a three or four part series during your child's routine immunizations starting at 2 months.
• Although pneumococcal vaccines have been used for older children and adults for many years, the American Academy of Pediatrics (AAP) now recommends a new form of pneumococcal vaccine for all children younger than age 2. This vaccine is called pneumococcal conjugate vaccine (PCV7).
• The AAP also recommends that PCV7 be given to all children ages 24 to 59 months of age that are at very high risk for pneumococcal infection. This includes children who have weakened immune (infection-fighting) systems, such as those with sickle cell disease and HIV infection (human immunodeficiency virus).

PCV7 can be given along with other childhood vaccines and is recommended at the following ages:

• 2 months
• 4 months
• 6 months
• 12 to 15 months

Children who are sick or have a fever should wait until they are well to get the PCV7 vaccine. Children who have had a prior reaction to any type of pneumococcal vaccine should not receive PCV7.

• For Neisseria meningitidis (meningococcal meningitis), a meningococcal vaccine is currently only used for high-risk groups. Immunization for the bacteria is not widespread due to its uncommon occurrence. Individuals who may require immunization include the following:
  • Asplenic children (children without a spleen)
  • College students (immunization of college students is recommended by the American College Health Association)
  • Military recruits
  • Individuals who are traveling to countries where the incidence of meningococcal infections is higher (parts of Africa)
  • Treatment of family members or close contacts of individuals with meningitis may be necessary if your child has the following type of bacterial meningitis:
    • H. influenzae type b
    • Neisseria meningitidis (meningococcal)

If you have questions regarding prevention, consult your child's physician.