Cryptococcal Meningitis: What Is It?
When the meninges inflame or become infected, it is known as meningitis. These are the membranes covering the brain and spinal cord. There are many different bacteria, viruses, fungi and other germs that cause the disease.
Most of the time, it is caused by a virus although cryptococcal meningitis (CM) is an exception. This is caused by two fungi: Cryptococcus gatti and Cryptococcus neoformans. It is extremely rare in those who are already healthy but is common in patients with immune systems that are already compromised, like those suffering from AIDS.
The Causes of CM
Most of the time Cryptococcus neoformans causes the infection and is in soil around the globe. Soil that has bird droppings is where it is most common.
The second fungus is located in the trees and is especially linked to eucalyptus trees. It is found around the bases of the trees in the debris.
CM is usually found in those who already have an immune system that has been compromised and not those who already have a good immune system. The gattii fungi is the one that is most commonly found to affect those who have a good immune system.
Cryptococcal Meningitis Symptoms
Most of the symptoms happen slowly but the following symptoms may be associated within a few weeks:
- Light sensitivity
- Vomiting and nausea
- Mental changes, including personality changes, hallucinations and confusion
A fever and stiff neck may also be noticed.
When untreated, CM can lead to:
- Hearing loss
- Hydrocephalus – “water on the brain”
- Brain damage
This is fatal when untreated, especially for those with AIDs/HIV. Between 10% and 30% of HIV patients with CM will die, according to the British Medical Bulletin.
Diagnosing Cryptococcal Menigitis
When your doctor suspects CM, a spinal tap will be performed. You will lie with your knees up to your chest and on your side. Your doctor will inject numbing agents into a cleaned part of your spine and then insert a needle. This will collect some spinal fluid for a sample to test for the disease. You may also find that your blood is tested.
A physical exam may also be performed to check for other symptoms of the disease.
Treating Cryptococcal Meningitis
Those who have CM will first be given drugs that have antifungal properties. Amphotericin B is the most common option and you will need to take it on a daily basis. You will be under the close watch of your doctor to make sure it is not toxic to the kidneys (nephrotoxicity). This is usually an intravenous drug, which goes straight into your veins.
Another antifungal drug is flucytosine, which can be taken at the same time as the first. This helps to treat the infection quickly.
During treatment, your doctor will need to take regular tests to make sure the CM is gone. You need to be clear of it for two weeks before stopping your medication. You will then switch to taking fluconazole on its own, which is for roughly eight weeks.
The Future for CM Patients
Those who have this type of meningitis will usually already have immune systems that have been compromised. It was extremely rare around the world before 1979 but became popular during the time that AIDs became an epidemic in 1980. The US Centers for Disease Control and Prevention states that there are between 0.4 and 1.3 cases of Cryptococcus neoformans infections per 100,000 people around the generally healthy people. This jumps to between two and seven when looking at HIV and AIDs patients. It is more common in the sub-Saharan parts of Africa, where the mortality rate is between 50% and 70% approximately.
Most patients find that they take fluconazole for the rest of their life, especially AIDs patients, to prevent suffering a relapse.