MENINGITIS

DEFINITION 

Meningitis is inflammation of the fluid that surrounds the brain and spinal cord. It is typically caused by a viral (most common) or bacterial infection, the latter of which is significantly more serious and can be fatal if untreated. Meningitis causes a headache, stiff neck, and fever, among other symptoms. It may produce more serious complications, such as seizures or loss of consciousness. Early diagnosis and accurate identification of the cause is important because management of the illness is directed by the symptom severity and the cause of the illness.

Meningitis, especially bacterial meningitis, is not common in the United States, largely as a result of routine immunization against the most common infectious causes.

Symptoms

The symptoms of meningitis can develop over hours, or they may worsen over several days. Meningitis is more common in children, although adults and teenagers can develop meningitis as well.

Symptoms of meningitis include:

• Severe headaches; mild or moderate headaches can be early symptoms

• Sensitivity to light with a headache

• Stiff neck; children may arch back the head or complain of pain when attempting to bend the head towards the chest. 

• Fever, ranging from low-grade (around 100.5 degrees) to high-grade (over 104 degrees)

• Irritability and restlessness

• Fatigue or sleepiness

• Nausea or vomiting

• A rash, which is usually non-blanching (doesn't turn white when you press on it); more common with meningococcal meningitis

• Seizures

• Mental status changes, such as confusion, lethargy, delirium, hallucinations, or even coma

Newborns and infants with meningitis don't have the same classic symptoms of meningitis. Instead, they may experience fussiness, excessive tiredness, diminished eating and drinking, and vomiting. The soft spot on the skull (fontanel) may also bulge.

 

Causes

There are many different microorganisms that can cause meningitis. Viruses, bacteria, and fungi may all result in the condition. The most common causes are contagious infections, which can be spread through the exchange of respiratory droplets by coughing, sneezing, kissing, or touching contaminated objects. 

Viral Meningitis
The term aseptic meningitis describes meningitis that is caused by something other than bacteria and is often used to describe viral meningitis.

Some viruses which may cause meningitis include:

• Enteroviruses are the most common viral cause of meningitis. Meningitis caused by enteroviruses is most common between June and October.

• Herpes viruses, including the chickenpox virus

• Measles virus

• Mumps virus

• Influenza virus

• West Nile virus is spread by a mosquito bite and is most common between August and October. In addition to meningitis symptoms, people with the virus often have a rash and swollen glands. West Nile virus has now been found in 46 states and about half of the people who develop the disease also develop meningitis or encephalitis.

• Lymphocytic choriomeningitis virus

Bacterial Meningitis

Bacterial meningitis tends to produce more severe infections than other types of meningitis, with a greater potential for long-term problems. The specific bacterial cause of meningitis generally varies with age.

The most common causes of bacterial meningitis in young infants are:

• E. coli

• Group B streptococcus

• Listeria monocytogenes

Bacterial causes of meningitis in young children include: 

•Streptococcus pneumoniae (pneumonococcus), which is the most common

• Neisseria meningitides (meninogococcus), the second most common

• Haemophilus influenzae type B (Hib): This was a more common cause of meningitis in children until the 1990s, but is now uncommon due to vaccination.

• Other possible causes, such as Lyme disease, syphilis, ehrlichiosis, leptospirosis, and tuberculosis

Less common causes of meningitis include fungal infections that affect the central nervous system; use of certain medications, such as nonsteroidal anti-inflammatory drugs (NSAIDs) and certain antibiotics, such as trimethoprim-sulfamethoxazole; and non-infectious conditions that are characterized by inflammation, such as autoimmune diseases (rare).

 

Treatment

Meningitis treatment depends on the severity and cause of the illness. Medication may be needed to not only treat the infection but to reduce inflammation and control the symptoms.

Pain and Fever Reduction

Regardless of the cause of meningitis, you might need to take pain medication to reduce the headaches and neck discomfort. Medications that reduce fever are also often needed. Over-the-counter medications are effective for most people.

Bacterial Meningitis
It is important that treatment for bacterial meningitis starts early in the course of the disease. Most people start with a combination of intravenous broad-spectrum antibiotics, which are likely to treat a wide variety of bacterial infections. The selection of antibiotics may change once the precise diagnosis is made. Sensitivities, tests that determine the antibiotics to which a specific bacterium is most susceptible, also help direct treatment. 

Different antibiotics may be used to treat young children, largely because meningitis is caused by different bacteria in different age groups. A combination of a third-generation cephalosporin and ampicillin, or cefotaxime or ceftriaxone plus vancomycin, will likely be used until the infectious organism has been identified. 

Viral Meningitis

With viral meningitis, the goal of treatment is primarily supportive care. Viral infections do not respond to antibiotic treatment, and most do not respond to specific antivirals.

Steroids

When meningitis is caused by an autoimmune disease, such as sarcoidosis or a drug reaction, steroids may be used to reduce inflammation.
 

Prevention

There are a number of strategies that can help prevent meningitis. While these approaches cannot completely eliminate your chances of getting meningitis, they can substantially reduce the risk. 

Hygiene

Avoiding common infections can reduce your chances of developing meningitis. The infectious organisms that cause meningitis are spread from person to person through respiratory droplets.

Avoiding infections is the most effective way to prevent meningitis for people of all ages. These precautions are especially important for young babies, who may not show signs of meningitis early and who may suffer more complications:

• Wash your hands often, especially when exposed to germs.

• Do not share personal hygiene items like toothbrushes.

• Disinfect surfaces regularly.

• Avoid close or prolonged contact with others who may have infections.