Meningitis, and How They Affect

¶ … meningitis, and how they affect the body. It will cover signs and symptoms, types of meningitis and causes of the disease. This paper will then discuss treatment and prevention (including preventing transmission of this highly contagious disease).

Etiology

Meningitis means an inflammation of the meninges, or the membrane around the brain and spinal cord. It can be caused by a number of factors, but infectious meningitis is due to multiplication of fungal, viral or bacterial organisms. All may develop as the result of a compromised immune system, and may be secondary to other infections in the body.

Bacterial meningitis occurs most frequently amongst children, although recent improvements in diagnosis and treatment of H. influenzae meningitis has resulted in a change of the mean age of those with bacterial meningitis from 15 months to 25 years (Schuchat).

Meningitis can be caused by a number of factors in addition to opportunistic bacterial or organism invasion. These causes can include ventriculostomy, sepsis, and tonsillitis (Mayhall CG). It has been a common opportunistic infection in patients with immune-compromising diseases, such as HIV.

Signs and Symptoms

All three forms of meningitis have similar symptoms. These may include fever and leukocytosis, headache, and the inability to bend one's head at the neck. The symptoms can be quite confusing, as they overlap those of many other diseases, including influenza, a generalized infection or a common cold. For babies, symptoms may also parallel those of viral meningitis.

These symptoms can include: fever, severe and persistent headache, vomiting, confusion, seizures (in more advanced cases), skin rash, confusion and a lower consciousness level, and a stiff neck (particularly when moving forward towards the chest).

These symptoms may not be as frequent in babies or older adults, partly because of their inability to communicate their symptoms. In young children, for example, the symptoms may resemble the flue, with cough, breathing difficulties and fever. In babies, the symptoms can include rash, vomiting, a reduced appetite and body stiffness.

One of the problems facing the medical staff in the Emergency Room upon admittance of a suspected meningitis is what type of meningitis it could be. The severe side effects of effective antibiotics may cause hesitation to start an antibiotics regimen if patient does not have bacterial meningitis. Many physicians feel compelled, however, to start antibiotic therapy if there is even a small suspicion, as fulminant bacterial meningitis can result in severe illness and death relatively quickly. This common wisdom was challenged in a study performed at Kaiser, which demonstrated that delay in most cases of bacterial meningitis did not result in a worse outcome for patients, with the exception of patients who are admitted with a history of clinically overt meningitis (Radetsky).

Viral meningitis proceeds relatively quickly. Symptoms, which are similar to bacterial meningitis but are less severe, appear within a week after infection, and disappear after about a week. It is relatively common, but does not result in serious consequences in most patients. It can be caused by a series of viruses. The most serious symptoms are generated by Eastern Equine Encephalitis, which is passed to humans through mosquitoes, but is rarely fatal except in cases where patients may be immune compromised. Most viral meningitis clears up within a week. It can be quite contagious.

Fungal meningitis generally occurs in patients who are immune compromised. The symptoms are similar to viral and bacterial meningitis. As with many opportunistic fungal infections of immune compromised patients, it can be quite serious, and treatment is difficult or impossible.

Diagnosis and Treatment

The biggest question for physicians treating patients with suspected meningitis is: "is it viral or is it bacterial?" Rapid tests for Neisseria meningitidis (meningococcus) and Haemophilus influenzae Type B have made it relatively easy to determine within a short period of time whether these are the causative agents. These tests are on CSF, however, which can be difficult and painful to extract from the patient. Since they are antibody tests, there can be a delay from onset of infection to production of antibodies; therefore, there can be a false negative early in the course of the disease.

Another indication is the presence of white blood cells in CSF. While the presence of white cells is indicative of a CSF infection, such as meningitis, an absence does not rule out the disease.

Treatment protocols vary depending on the type of meningitis. Viral meningitis treatment is generally palliative only -- pain relief and bed rest. In some cases where the patient is particularly sick, there may be some antiviral drugs given, although they are usually not effective unless given early in the course of the disease.

Other than rapid antibody tests, there are no techniques which allow for rapid bacterial CSF isolation and differentiation. In some cases, the low number of CFU's in the CSF requires multiplication through PCR or enriched media used for septicemia testing. An isolation step is then required, and after 24-48 hours one can take one or more CFU's and run an antimicrobial susceptibility test.