Meningitis
Kat Wetjen
Bacterial Meningitis
mening- membrane
itis- inflammation
Meningitis is an infection that causes inflammation of the thin layer of tissue, called meninges, which cover the brain and spinal cord.
Causes
Acute bacterial meningitis occurs when bacteria enters the bloodstream and migrate to the brain and spinal cord. It can also occur when the bacteria directly invades the meninges.
- Streptococcus pneumoniae (pneumococcus) Most common cause of bacterial meningitis in infants, young children and adults in the United States. It more commonly causes pneumonia or ear or sinus infections
- Neisseria meningitidis (meningococcus). This commonly occurs when bacteria from an upper respiratory infection enters your bloodstream. This infection is highly contagious. It affects mainly teenagers and young adults, and may cause local epidemics in college dormitories, boarding schools and military bases.
- Haemophilus influenzae (haemophilus). The leading cause of bacterial meningitis in children.
- Listeria monocytogenes (listeria). These bacteria can be found in soft cheeses, hot dogs and luncheon meats. Most healthy people exposed to listeria don't become ill, but pregnant women, newborns, older adults and people with weakened immune systems tend to be more susceptible. Listeria can cross the placental barrier, and infections in late pregnancy may cause a baby to be stillborn or die shortly after birth.
Signs and Symptoms
- Stiff neck
- Fever
- Headache
- Nausea
- Vomiting
- Altered mental status (confusion)
Transmission
The germs that cause bacterial meningitis can be contagious. Some can spread through the exchange of respiratory and throat secretion (example:kissing). Bacteria is not spread by causal contact or breathing the air of someone infected with meningitis. Most meningitis-causing bacteria is not spread person-to-person but can cause disease because the person has certain risk factors.
Diagnosis
- Sample of blood- see if it grows microorganisms
- Spinal tap- cerebrospinal fluid (near spinal cord)
- X-rays and CT scans- check for swelling
- If bacteria present they can be grown (cultured) to confirm the specific type of bacteria that is causing the infection and then decide which antibiotic will work best
Risk Factors
- Age (infants and elderly)
- Weak immune system
- Community settings
- Skipping vaccinations
Treatment/Prognosis
- Antibiotics- depends on bacteria, extent of infection, your age, how likely you are to have complications during illness
- Treatment started as soon as possible
- Antibiotic treatment reduce risk of dying from meningitis to below 15%
- 25-30% of people die
- 60% of infants survive but have complications (hearing loss, brain damage, developmental difficulties)
Complications
- If not treated right away, it can lead to death within hours or permanent damage to the brain and other parts of the body
- Hearing loss
- Memory difficulty
- Learning disabilities
- Brain damage
- Seizures
- Kidney Failure
- Shock
- Permanent neurological damage
- Death
Research Advances
Team led by Dlawer Ala'Aldeen recently discovered that the three pathogens target the same receptor on the human cerebrovascular endothelial cells. These cells are responsible for filtering the system that protects our brain from disease. This enables the bacteria to cross the blood-brain barrier.
They are hoping this will help find new strategies for the prevention and treatment of bacterial meningitis.