MENINGITIS

OVERVIEW

What exactly is meningitis you may ask?

Although a rare condition, it is a life-threatening disease and a cause of great concern that we all need to be well informed about. The meninges refer to the three coverings or protective membranes that protect the brain and spinal cord. So basically, meningitis is the inflammation of the meninges of the brain or spinal cord.

WHAT ARE THE TYPES OF MENINGITIS?

There is no fixed classification for meningitis. However, the disease is categorized into types based on the exact cause of the inflammation, whereby the exact causes can be grouped under infectious and non-infectious causes.

Infectious causes are when an organism enters into the bloodstream and is transmitted to the brain and spinal cord, where it causes the infection. Non-infectious causes, on the other hand, is not abused by an infection but rather a condition or certain drugs.

There are four main types of meningitis, which are grouped under the infectious kind and they include:

– bacterial meningitis
– viral meningitis
– fungal meningitis and
– parasitic meningitis. (Viral and bacterial meningitis are the most common types of meningitis).

• Bacterial meningitis

Bacterial meningitis: is a form of meningitis which occurs when bacteria like Haemophilus influenza, Streptococcus pneumonia and Neisseria meningitides gains access into the bloodstream. They then travel to the brain and spinal cord causing infection and inflammation. It is transmissible by direct contact or indirect contact with an infected person through kissing, coughing, sneezing or even by transfer of saliva through the mouth to mouth resuscitation. It is a serious condition which can result in death if untreated.

• Viral meningitis

Viral meningitis: is by far the most common type of meningitis with a greater number of cases being caused by Enteroviruses such as (coxsackievirus A and B and echovirus). Viral meningitis can be spread by faecal contamination when there is improper washing of hands after using the toilet. Aside from enteroviruses, meningitis can be caused by:
– Influenza virus,
HIV,
– Herpes virus
– Measles
– Chickenpox
– Rubella virus

• Parasitic meningitis

Parasitic meningitis is not as common as the previously mentioned causes. It is caused when a person eats the products of animals which have been infected by parasites.

Primary amoebic meningiocephalitis (PAM) is a very rare and fatal type of parasitic meningitis caused by Naegleria Fowleri. This type of meningitis causes a rapidly progressive brain infection and usually ends up in death. this parasite has been found living in soil, poorly treated swimming pools, water heaters and warm freshwater sources. The parasite enters its host through the nasal passage by inhalation and travels to the brain where it destroys the brain tissue.

 • Fungal meningitis

Among all the types of meningitis, fungal meningitis is the rarest form and is caused by a fungal infection. These fungi are spread by various means, mainly through inhalation of soil infected with the spores and hyphae of fungi and through contact with animal droppings. The most common kinds of fungi involved in fungal meningitis include Coccidioides, Blastomyces, Cryptococcus and Histoplasma.

The most common cause of fungal meningitis in people with weakened immune systems is Cryptococcus and is one of the most common causes of meningitis in adults in Africa.

Patients with a weakened immune system are at a higher risk of developing fungal meningitis

 • Non-infectious meningitis

This form of meningitis is not caused by inflammation of the meninges but rather other conditions such as;

• cancer
• the use of certain medications
• brain surgery
• connective tissue disorders or
• systemic disorders.

SIGNS AND SYMPTOMS OF MENINGITIS

Generally, the classical signs of all kinds of meningitis are headache, fever and a stiffened neck.

However, in a narrowed spectrum, there are certain signs and symptoms which are specific to the exact causes of meningitis. For example, there are more similarities when it comes to the meningitis of viral or bacterial origin.

Symptoms of Bacterial meningitis

Symptoms of bacterial meningitis normally occur as a sudden and acute onset and include;

• Headache
• fever and
• a stiffened neck as the main clinical symptoms.

Other symptoms which may occur at a later stage, normally within three to seven days of the infection include;

• sensitivity to light

• altered mental status

• nausea

• vomiting

• confusion and

• a rash. which is due to damage and leakage of blood from cells around the blood vessels by the reproduction of bacteria.

The broad nature of these symptoms makes it difficult for early diagnosis of the disease since the symptoms can be mistaken for the flu.

Symptoms of Viral meningitis

The symptoms of viral meningitis even though similar to that of bacterial meningitis, are less severe.

The main distinguishing factor between bacterial and viral meningitis is that viral meningitis is aseptic. Aseptic, meaning that even though there is the presentation of the same signs and symptoms, a routine blood test shows no evidence of bacteria in the blood.

Symptoms of Parasitic meningitis

The symptoms of parasitic meningitis appear one to seven days after the infection especially in the case of primary amoebic meningoencephalitis(PAM).

These symptoms include the classical signs of headache, fever and stiff neck as well as the loss of balance, hallucination, seizures and altered mental status.

Diagnosing meningitis

Like the diagnosis of any other medical condition, meningitis requires a thorough physical examination as well as detailed history taking. Certain important key points like age, occupation, travel history, diet and current or previous medication can help your health physician reach an early diagnosis of your condition.

The classical signs of meningitis; stiff neck, fever and headache will be evident.

Aside from the physical examination and history, you would be required by your doctor to do a series of tests to reach a conclusion. These tests include:

• A lumbar puncture: this is a procedure where a sample of your cerebrospinal fluid, the fluid that cushions your brain and spinal cord is collected and tested for an increase in pressure or the absence of bacteria or other microorganisms. It is a standard diagnostic procedure for meningitis.

• A full blood count to check the number of white blood cells and red blood cells and to identify if there is an increase in the white blood cell count. An increased white cell count is an indication of infection and is seen in meningitis especially of an infectious cause.

• A blood culture which is another routine test is usually done to identify the type of bacteria present in bacterial meningitis.

• A chest X-ray will be required to identify the presence of an abscess or bleed or sinusitis.

Is Meningitis curable?

Meningitis is not only a curable disease but also a preventable disease. Preventive measures can be taken by having vaccinations which are readily available.

These vaccinations are for different kinds of bacterial meningitis as well as viral meningitis.

The two main vaccines available for bacterial meningitis are;
• meningococaLconjugate vaccine and
• MenB.

Meningococcal conjugate vaccine protects against most types of meningococcal disease and has a longer period of action as compared toMenB which lasts for a shorter period of time and is limited to a specific strain of bacteria.

Unlike viral and bacterial meningitis where vaccinations are available, there are no available vaccinations for fungal or parasitic meningitis.

For treatment, the course is dependent on the causes of the patients’ meningitis.

Bacterial meningitis is a severe and life-threatening condition and so requires instant attention and treatment. The patient must be admitted straightway to prevent complications and death. Antibiotics are given intravenously.

Viral meningitis is treated with intravenous antiviral medications if the disease does not resolve on its own.

Meningitis caused by fungal or parasitic microorganisms requires intensive and continuous antifungal and antibiotic treatment respectively to deal with both the symptoms as well as the direct cause of the disease. In the case of fungal infections, the disease may resolve on its own without any treatment based on the exact fungi.

Treatment involves, administering high doses of intravenous antifungal drugs. The duration of the treatment is dependent on the patient’s immunity as well as the exact fungus causing the disease.