What Is Meningitis?
Learn the causes of meningitis as well as the symptoms and treatment. What age groups are susceptible?
Meningitis is the general name for inflammation of the meninges (sheaths that cover the brain and spinal cord) and the cerebrospinal fluid. Infectious agents such as bacteria, viruses, fungi, or organisms like protozoa and rickettsia can cause meningitis.
The usual cause of meningitis is the arrival of microorganisms from an infection elsewhere in the body. These come through the blood into the cerebrospinal fluid. Streptococcus Pneumoniae and Neisseria Meningitidis are the organisms that cause meningitis in children. Escherichia Coli may cause meningitis in newborns.
The infection usually begins in the respiratory system. Occasional sources of meningitis are infection of heart valves, bones, or other parts of the body as well as bacteria near the central nervous system from infected ears, nose, or teeth.
The signs and symptoms of meningitis vary and depend on the age of the child with the infection and which bacterial or viral agent is causing it. The first signs may be symptoms of illnesses like hay fever, tiredness, vomiting, and irritability. Older children may get headaches. A doctor may find a stiff neck when the child is examined. About a third of patients may experience seizures with bacterial meningitis. As the disease progresses, other symptoms may appear, such as increased irritability with crying and difficulty breathing.
Newborns with meningitis may lack the signs described above and may simply be very irritable or have decreased consciousness. Normally, when a baby isn't feeling well, she is comforted when her mother picks her up. With meningitis, we sometimes see "paradoxical irritability," when picking up and rocking a child may make her more disturbed.
Other signs in an infant with meningitis may include jaundice and stiffness of the body and of the neck. There may be bulging of the soft spot at the top/front of the baby's skull. A purple rash may accompany Meningococcal meningitis in half of the cases. Other kinds of bacterial meningitis, such as those caused by Streptococcus Pneumoniae and Haemophilus Influenzae, also may have a similar rash.
Invasive meningococcal infections may be complicated by arthritis, inflammation of the heart muscle, pericarditis or pneumonia.
Seventy percent of all cases of meningitis occur between the ages of one and five, with the peak between six and 12 months. There are no specific signs and symptoms that can distinguish bacterial meningitis from other causes.
In some cases it may be advisable to administer antibiotics to those people in close contact with the patient in order to prevent more cases. The use of immunization against Haemophilus Influenzae Type B (HIB) has dramatically decreased meningitis caused by this organism. All children are advised to receive this vaccination. Some high-risk children should also be immunized against Streptococcus Pneumoniae.
The need for incubation varies with the organism and the cause of the meningitis. Once the organisms have entered the cerebrospinal fluid, the body's defenses cannot fight their growth as when the organisms were in the bloodstream. Once the bacteria have entered the spinal fluid, symptoms show up quite rapidly.
The duration of the disease is variable, as bacterial meningitis can occur acutely (one to 24 hours), subacutely (one to seven days) or chronically (more than a week). Once established meningitis takes many days or even weeks to resolve. Meningitis is usually infectious and patients may be contagious until antibiotic therapy has been initiated for about 24 hours. Meningitis must be treated in a health care facility.
All children with meningitis require aggressive measures for diagnosis and treatment. This typically means a lumbar puncture in order to obtain a culture of spinal fluid for examination. Once diagnosed, intravenous antibiotics are given as soon as possible, even before the exact cause of the infection is known. The antibiotics can be changed once the infecting microorganism is identified. A combination of antibiotics may be prescribed. Corticosteroids may be necessary to fight the inflammatory response.
The first three or four days of treatment of bacterial meningitis are critical. Vital signs such as pulse and respiration must be monitored frequently until the patient is stable. Since hearing loss may result from this illness, children should be tested for hearing after recovery.
If you suspect meningitis or if your child shows symptoms such as vomiting, headache, lethargy or confusion, neck stiffness, rash, and fever seek medical attention. In infants, look for fever, irritability, poor feeding, and lethargy. If your child has had contact with other children with meningitis, see your doctor to check if vaccination is appropriate.