Meningitis - meningococcal Health Article

Definition

Meningococcal meningitis is an infection that causes inflammation of the membranes covering the brain and spinal cord.

Alternative Names

Meningococcal meningitis

Causes, incidence, and risk factors

Meningococcal meningitis is caused by the bacterium Neisseria meningitidis (also known as meningococcus).

Most cases of meningococcal meningitis occur in children, from infancy to adolescence. Meningococcus is the most common cause of bacterial meningitis in children and the second most common cause of bacterial meningitis in adults.

The onset of the disease may be rapid and may start with an upper respiratory infection or sore throat. The infection occurs more often in winter or spring and may cause local epidemics at boarding schools, college dormitories, or military bases.

Risk factors include recent exposure to meningococcal meningitis and recent upper respiratory infection.

Symptoms

• Rash, pinpoint red spots (petechiae)
• Purple, bruise-like areas (purpura)
• High fever
• Severe headache
• Severe malaise (general ill feeling)
• Nausea
• Vomiting
• Stiff neck
• Sensitivity to light (photophobia)
• Mental status changes

Signs and tests

Physical examination will reveal low blood pressure, fast heart rate, stiff neck, and a possible rash.

Other tests include the following:

• White blood cell (WBC count is higher than normal.
• Spinal tap for spinal fluid (CSF) shows increased white blood cells, low glucose, high protein.
• Special stains of spinal fluid sometimes show the meningococcus bacteria.
• CSF culture grows the meningococcus bacteria.
• Blood culture grows the meningococcus bacteria.
• CT scan of the brain is usually normal.

Treatment

Early diagnosis and treatment is extremely important to prevent serious illness or death.

Antibiotics such as ceftriaxone are prescribed and given by an IV (intravenous line). Other medicines may be used to treat the complications due to increased spinal fluid pressure.

Sometimes steroid medication is used, more often in children than adults.

People in close contact with someone with meningococcal meningitis should be given antibiotics to prevent infection. Such people include household members, roommates in dormitories, or those who come in contact with respiratory secretions of an infected person.

Expectations (prognosis)

The death rate ranges from 5% to 15%, with young children and adults over 50 having the highest risk of death.