Meningitis in Children

Meningitis is a term used to describe an inflammation of the membranes that surround the brain or the spinal cord. Meningitis, especially bacterial meningitis, is a potentially life-threatening condition that can rapidly progress to permanent brain damage, neurologic problems, and even death. Doctors need to diagnose and treat meningitis quickly to prevent or reduce any long-term effects.

• The inflammation causing meningitis is normally a direct result of either a bacterial infection or a viral infection. However, the inflammation can also be caused by more rare conditions, such as cancer, a drug reaction, a disease of the immune system or from other infectious agents such as fungi (cryptococcal meningitis) or parasites.
• Normally, meningitis causes fever, lethargy, and a decreased mental status (problems thinking), but these symptoms are often hard to detect in young children.
• If the infection or resulting inflammation progresses past the membranes of the brain or the spinal cord, then the process is called encephalitis (inflammation of the brain).
• The highest incidence of meningitis is between birth and 2 years, with the greatest risk immediately following birth and at 3-8 months of age. Increased exposure to infections and underlying immune system problems present at birth increase an infant's risk of meningitis.

The focus of this article will be on the common infectious causes of meningitis as they account for the large majority of problems; however, less common causes will be presented.

Bacteria and viruses cause the great majority of meningitis disease in infants and children. The most serious occurrences of meningitis are caused by bacteria; viral-caused meningitis is common but usually is less severe and, except for the very rare instance of rabies infection, almost never lethal. However, both bacterial and viral types of the disease are contagious.

Meningitis normally occurs as a complication from an infection in the bloodstream. A barrier (called the blood-brain barrier) normally protects the brain from contamination by the blood. Sometimes, infections directly decrease the protective ability of the blood-brain barrier. Other times, infections release substances that decrease this protective ability.

Once the blood-brain barrier becomes leaky, a chain of reactions can occur. Infectious organisms can invade the fluid surrounding the brain. The body tries to fight the infection by increasing the number of white blood cells (normally a helpful immune system response), but this can lead to increased inflammation. As the inflammation increases, brain tissue can start swelling and blood flow to vital areas of the brain can decrease due to extra pressure on the blood vessels.

Meningitis can also be caused by the direct spread of a nearby severe infection, such as an ear infection (otitis media) or a nasal sinus infection (sinusitis). An infection can also occur any time following direct trauma to the head or after any type of head surgery. Usually, the infections that cause the most problems are due to bacterial infections.

• Bacterial meningitis can be caused by many different types of bacteria. Certain age groups are predisposed to infections of specific types of bacteria.
  • Immediately after birth, bacteria called group B Streptococcus, Escherichia coli, and Listeria species are the most common.
  • After approximately 1 month of age, bacteria called Streptococcus pneumoniae, Haemophilus influenzae type B (Hib), and Neisseria meningitidis are more frequent. The widespread use of the Hib vaccine as a routine childhood immunization has dramatically decreased the frequency of meningitis caused by Hib.
• Viral meningitis is much less serious than bacterial meningitis and frequently remains undiagnosed because its symptoms are similar to the common flu. The frequency of viral meningitis increases slightly in the summer months because of greater exposure to the most common viral agents, called enteroviruses.

Other more rare causes of meningitis that are noninfectious are cancers, head injury, brain surgery, lupus, and some drugs. There is no person-to-person transmission from these relatively rare causes.

In infants, the signs and symptoms of meningitis are not always obvious due to the infant's inability to communicate symptoms. Therefore, caregivers (parents, relatives, guardians) must pay very close attention to the infant's overall condition. The following is a list of possible symptoms seen in infants or children with bacterial meningitis (bacterial meningitis at any age is considered a medical emergency):

• Classic or common symptoms of meningitis in infants younger than 3 months of age may include some of the following:
  • Decreased liquid intake/poor feeding
  • Vomiting
  • Lethargy
  • Rash
  • Stiff neck
  • Increased irritability
  • Increased lethargy
  • Fever
  • Bulging fontanelle (soft spot on the top of the head)
  • Seizure activity
  • Hypothermia (low temperature)
  • Shock
  • Hypotonia (floppiness)
  • Hypoglycemia (low blood sugar)
  • Jaundice (yellowing of skin)
• Classic symptoms in children older than 1 year of age are as follows:
  • Nausea and vomiting
  • Headache
  • Increased sensitivity to light
  • Fever
  • Altered mental status (seems confused or odd)
  • Lethargy
  • Seizure activity
  • Coma
  • Neck stiffness or neck pain
  • Knees automatically brought up toward the body when the neck is bent forward or pain in the legs when bent (called Brudzinski sign)
  • Inability to straighten the lower legs after the hips have already been flexed 90 degrees (called Kernig sign)
  • Rash

Symptoms of viral meningitis most commonly resemble those of the flu (fever, muscle aches, cough, headache but some may have one or more of the symptoms listed above for bacterial meningitis), but the symptoms are usually considerably milder.

If a caregiver is concerned that a child has developed meningitis, immediate medical evaluation of the child is essential. Because meningitis is a medical emergency, treatment at a hospital's emergency department is more appropriate than at a doctor's office. If transportation is not available, a caregiver should immediately call 911 for emergency medical services to have the child brought to a hospital's emergency department.

Meningitis is a disease that needs prompt diagnosis and aggressive treatment, especially if it is bacterial. A doctor must perform specific tests to check for the type (usually bacterial or viral) of meningitis. Meningitis cannot be diagnosed over the phone or simply based on a telephone description of the situation.

Upon arrival at the emergency department, the child's temperature, blood pressure, respiratory rate, pulse, and oxygen in the blood may be checked. After quickly checking the child's airway, breathing, and circulation, the doctor completely examines the child to look for a focal source of infection, to assess any alteration in mental status, and to determine the presence of meningitis. If meningitis is suspected, several tests and procedures are needed to determine the diagnosis. However, early IV antibiotic treatment is often started before tests are done. In some children, the diagnosis of fifth disease (fever, cold symptoms, followed by a rash especially on the face) or other viral infection is deemed most likely and the child will usually not need the following tests:

• A spinal tap, or lumbar puncture, is an essential procedure in which cerebrospinal fluid is obtained from the child and then analyzed in a laboratory. Cerebrospinal fluid is the fluid surrounding the brain and spinal cord where the infection in meningitis occurs.
  
  Occasionally, a CT of the brain is done before the spinal tap if other problems are suspected by the doctor (see below); most clinicians will treat the child with antibiotics before the spinal tap if bacterial-caused meningitis is strongly suspected because of the possibility of a rapid decline in condition of the patient.
  • To perform this simple procedure, the doctor numbs the skin on the child's lower back with a local anesthetic.
  • A needle is then inserted into the lower back to obtain the necessary fluid from inside the spinal cord because the fluid bathing the spinal nerves is essentially the same that bathes the brain.
  • The fluid is sent to a laboratory and is checked for white and red blood cells, protein, glucose (sugar), and organisms (bacteria, fungus, parasites; viruses are not visualized). The fluid is also sent for culture (cultures may take about a week for viruses).
  • After the needle is removed, a small bandage is placed on the skin where the needle was inserted.
  • A spinal tap is not a dangerous procedure for a child. The needle is inserted at a location below the end of the main body of the spinal cord. A spinal tap is a simple procedure that is necessary to determine if a person has meningitis. Currently, no other procedure is available to aid in the diagnosis of meningitis.
• An IV may be started to obtain blood and to give fluids. This helps prevent dehydration and maintain a good blood pressure.
• Urine may be obtained to determine if any infection is present in the child's urinary tract system.
• A chest X-ray film may be taken to look for signs of infection in the child's lungs.
• A CT scan is sometimes necessary if any of the following is present or suspected:
  • Trauma
  • Increased brain pressure
  • Neurologic problem
  • Lack of fever
  • Brain abscess
  • Tumor

Meningitis, especially bacterial-caused, can be a rapidly progressing, life-threatening disease, so immediate medical care is important if meningitis is suspected in a child. If the child's condition is rapidly deteriorating, call 911 for transport. There is no home treatment for bacterial-caused meningitis.

• Sometimes, children are sent home from the emergency room if the doctor is confident that the child has viral meningitis. Frequently, a child with viral meningitis can be treated successfully at home by taking acetaminophen (Tylenol) or other pain medications and by drinking plenty of fluids. If a child has viral meningitis, follow-up care is still important.
• Have the child reevaluated within one to two days to be sure that he or she is improving.
• Watch for any worsening signs or symptoms and if necessary, return immediately to a medical facility.

Because meningitis is a potentially life-threatening infection, therapy (IV antibiotics) may begin before all of the tests are performed and prior to having all of the results available.

• If any indication of respiratory distress is present, a breathing tube (intubation) may be needed to provide oxygen to help the child breathe.
• A heart and breathing monitor is connected to accurately monitor the child's vital signs (respiratory rate, oxygen level, heart rate and rhythm).
• An IV is started to give fluids and to correct any dehydration. An IV also helps to maintain blood pressure and good circulation.
• A tube (catheter) may be placed in the bladder to obtain urine and to help accurately measure the child's hydration.
• A child who has bacterial meningitis or is suspected to have bacterial meningitis is admitted to the hospital. The type of monitoring, such as in a pediatric intensive-care unit, is determined by the doctor in the emergency department and the doctors who care for the child in the hospital.
• A child who has viral meningitis and is improving may be sent home for supportive therapy. Supportive therapy includes encouraging fluids to prevent dehydration and giving acetaminophen (Tylenol) or ibuprofen (Motrin) for pain and fever. If the child is sent home, a doctor must check the child within 24 hours to make certain his or her condition has improved.

• Antibiotics may be given early in treatment of meningitis to help fight the infection as quickly as possible. The type of antibiotic depends on the child's age and any known allergies. Antibiotics are not helpful for viral meningitis.
• Steroids may be given to help minimize inflammation depending on which organism is suspected to be causing the infection.
• More aggressive medications may be necessary depending on the severity of the child's illness.

In general, the Infectious Diseases Society recommends vancomycin plus ceftriaxone or cefotaxime IV be used; the extent (time span) of treatment may vary with the bacterial species being treated. The treatment may vary from about seven to 21 or more days.

Fungal or parasitic infections require special drugs to treat these relatively rare infections and usually are managed by infectious disease specialists.

Noninfectious causes of meningitis, which are rare, are treated according to the underlying problem(s) such as cancer, drug-induced, or surgical problems.

If a child is sent home from the emergency department or hospital, a follow-up visit should be arranged with the doctor within 24 hours of the child's release. If the child's condition does not improve or worsens, an immediate return to the emergency department is warranted.

Specific vaccines are available to protect and reduce the chances of developing both the bacterial and viral types of meningitis. The antibacterial vaccines include Hib, meningococcal, and pneumococcal and the antiviral vaccines include influenza, varicella, polio, measles, and mumps. Two tables show the CDC recommended vaccines for infants and children up to age 18 as of 2014 (most recent available) that include those that protect or reduce the chances for certain bacterial and viral meningitis infections and other infections. For details, please see the two tables found at these two CDC sites listed below:

http://www.cdc.gov/vaccines/parents/downloads/parent-ver-sch-0-6yrs.pdf

http://www.cdc.gov/vaccines/who/teens/downloads/parent-version-schedule-7-18yrs.pdf

For details on the above two tables, pleases see the following link to the CDC site: http://www.cdc.gov/vaccines/schedules/index.html

Vaccines against Hib and S. pneumoniae have markedly reduced the number of infected children. Also, if a child has not obtained vaccination against N. meningitidis, in some states they will not be allowed to attend college classes until they prove they are vaccinated.

Antibiotics are given to all intimate contacts of a child with meningococcal meningitis, a very specific type of bacterial meningitis. These intimate contacts may include family members, friends, health-care workers, and even day-care or nursery contacts. Adults can contract this type of meningitis and become carriers of these bacteria. If adults have been given preventive antibiotics and then become sick or develop any symptoms, they need a full medical evaluation. Preventive antibiotics are not needed for cases of viral meningitis or with other types of bacterial meningitis except for some relatives or caregivers who are caring for patients with Hib infections.

Vaccine side effects vary from none to transient pain or discomfort at the inoculation site. Some children may develop a mild fever, headache, and feel tired. In most individuals who get these side effects, Tylenol can reduce the discomfort. These effects rarely last more than 24 hours. Infrequently, some children may develop more severe allergic reactions (swelling, short of breath, Guillain-Barré syndrome); these individuals should not be given vaccine. Consultation with a pediatric specialist (allergy and/or infectious disease) is recommended.

The prognosis for any type of meningitis depends on the exact cause and severity of infection. At the time of initial treatment and diagnosis, a doctor may not be able to tell a person the exact prognosis and possible recovery outlook.

• Bacterial meningitis can rapidly progress within hours and end in death despite the most advanced medical care. If a child survives a severe case of bacterial meningitis, the child may have long-term disabilities, including visual troubles, hearing difficulty, seizures, paralysis, and decreased mental function.
• In very mild cases of bacterial meningitis that are treated early, a child may completely recover over the course of a few weeks with rehabilitation.
• Viral meningitis tends to be a much less severe infection and normally can be treated at home on an outpatient basis. Most children with viral meningitis get better within two weeks.