US Pharm. 2023;48(4):15-16.

Brain and Spinal Cord Membrane Inflammation

Meningitis is defined as inflammation of the meninges, the three delicate membranes protecting the brain and spinal cord. It can be a life-threatening disease caused by viruses, bacteria, fungi, or parasitic infections. Noninfectious conditions such as drug ingestion, cancer, and autoimmune disorders can also lead to meningitis. It can affect anyone but is most prevalent in younger people. With the introduction of flu vaccines and the meningococcal vaccine, the rate of meningitis has decreased in the United States in recent years.

Person-to-Person Spread

Outbreaks of viral meningitis typically occur in the summer and early fall, whereas bacterial meningitis frequently occurs in the winter. Viral meningitis is milder than other forms of meningitis and resolves on its own within 7 to 10 days. In bacterial meningitis, a bacterium enters the meninges directly from the bloodstream, a sinus or ear infection, or a skull trauma. Bacteria that cause meningitis include Neisseria meningitidis (meningococcal meningitis), Streptococcus pneumoniae (pneumococcal meningitis), group B streptococcus (meningitis in newborns), Haemophilus influenzae type b, and Listeria. Bacterial meningitis is associated with a higher mortality rate (10%-15%) and greater risk of long-term disability than viral meningitis.

The viruses that cause viral meningitis can be passed from person to person. Still, these infections do not always cause meningitis. Progression to viral meningitis is most likely to occur in infants and people with immune deficiency. Bacterial meningitis is contagious and is spread through respiratory secretions by coughing or sharing utensils. Preteens, teens, college students living in dormitories, and travelers to certain foreign countries are most likely to develop bacterial meningitis. People exposed to someone with a confirmed case of meningococcal meningitis should be treated with antibiotics to prevent the spread of the disease. Vaccination campaigns may be conducted to avoid further meningococcal meningitis outbreaks.

The telltale symptoms of meningitis include a stiff neck, severe headache, fever, sensitivity to light, confusion, drowsiness, and nausea or vomiting. In children, symptoms are lack of appetite, drowsiness, and, in the case of infants, constant crying that may worsen when the baby is held. In adults and children, symptoms can appear within hours or over several days.

Diagnosis and Rapid Treatment Essential 

Early diagnosis and rapid treatment of patients with meningitis are essential to prevent potentially serious complications, such as permanent neurologic damage and loss of hearing or vision. Laboratory tests include nose or throat cultures, blood cultures, and a head CT scan. A lumbar puncture (spinal tap) is performed to determine whether the fluid in the brain and spinal cord (cerebrospinal fluid) contains bacteria, inflammatory cells, or an abnormal glucose concentration.

It can be difficult to rapidly identify if a virus, bacterium, or something else led to meningitis. For this reason, doctors may start antibiotics quickly if a bacterial cause is suspected but before blood or cerebrospinal fluid culture results come in. Treatment of meningitis includes IV fluids and fever-reducing medications, IV antibiotics (in the case of bacterial meningitis), and bed rest. Antibiotics are not helpful in the treatment of viral meningitis. Antiviral medicine is rarely prescribed and may help people with meningitis caused by herpesvirus and influenza. Hospitalization is sometimes necessary, especially in serious cases of bacterial meningitis.

Vaccines are available that can protect against the development of some forms of bacterial meningitis. Haemophilus influenzae type b vaccine protects against Haemophilus meningitis. The meningococcal vaccine protects against Neisseria meningitidis, which causes one of the deadliest and most contagious forms of bacterial meningitis. The pneumococcal vaccine provides excellent protection against Streptococcus pneumoniae meningitis. It is imperative that infants and children receive the appropriate vaccinations as recommended by their healthcare professionals to prevent these forms of bacterial meningitis as well as other preventable infectious diseases. Vaccines do not protect against infections from all bacterial types (strains). There is still a chance that vaccinated people can develop bacterial meningitis, although this is less common.

The content contained in this article is for informational purposes only. The content is not intended to be a substitute for professional advice. Reliance on any information provided in this article is solely at your own risk.

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