What Is Cryptococcal Meningitis?
Meningitis is an infection and
inflammation of the meninges, which are the membranes that cover the brain and
spinal cord. Meningitis can be due to many different germs, including bacteria,
fungi, and viruses.
Two types of
fungus can cause cryptococcal meningitis (CM). They are called Cryptococcus neoformans (C.
neoformans) and Cryptococcus gattii (C.gattii). This disease is
rare in healthy people. CM is more common in people who have compromised immune
systems, such as people who have AIDS.
What Are the Symptoms of Cryptococcal Meningitis?
The symptoms of CM usually come on slowly.
Within a few days to a few weeks of contact, an infected person may develop the
- a headache
- mental changes, including confusion,
hallucinations, and personality changes
- sensitivity to light
In some cases, the infected person may
experience a stiff neck and fever.
If it’s left untreated, CM may lead to
more serious symptoms, such as:
- brain damage
- hearing loss
- hydrocephalus, which is also called “water on
Eventually, untreated CM is fatal,
especially in people with HIV or AIDS. According to the British Medical Bulletin, 10
to 30 percent of people with HIV-related CM die
from the illness.
What Causes Cryptococcal Meningitis?
A fungus called C. neoformans causes
most cases of CM. This fungus is found in soil all over the world.
It’s usually found in soil that contains bird droppings.
also causes CM. It isn’t found in bird droppings. Instead, it’s associated with
trees, most commonly eucalyptus trees. It grows in the debris around the base
of the eucalyptus tree.
CM usually occurs in people who have a
compromised immune system. It rarely occurs in someone who has a normal immune
system. C. gattii is more likely to infect someone with a healthy
immune system than C. neoformans.
How Is Cryptococcal Meningitis Diagnosed?
If your doctor suspects you might have
CM, they’ll perform a spinal tap. During this procedure, you’ll lie on your
side with your knees close to your chest. Your doctor will clean an area over
your spine, and then they’ll inject numbing medication. Your doctor will insert
a needle and collect a sample of your spinal fluid. A lab will test this fluid
to find out if you have CM. Your doctor may also test your blood.
Your doctor will also perform a
physical examination when trying to figure out if you have CM. They’ll look for
the symptoms associated with this disease.
How Is Cryptococcal Meningitis Treated?
You’ll receive antifungal drugs if you
have CM. The most common choice is amphotericin B. You’ll need to take the drug
daily. Your doctor will monitor you closely while you’re on this drug to watch
for nephrotoxicity (meaning the drug is toxic to your kidneys). You’ll
typically receive amphotericin B intravenously, which means directly into your
You’ll probably also take flucytosine,
another antifungal medication, while you’re taking the amphotericin B. This
combination helps treat the condition more quickly than amphotericin B alone.
You’ll need to get spinal fluid
testing repeatedly during treatment. If your tests have come back negative for
CM for two weeks, your doctor will probably ask you to stop taking amphotericin
B and flucytosine. You’ll probably switch to taking only fluconazole, which you’ll
keep taking for about eight weeks.
What Is the Long-Term Outlook?
Most people who develop CM already
have severely compromised immune systems. According to the U.S. Centers for Disease Control and Prevention,
infections by C. neoformans occurs yearly in about 0.4 to 1.3
cases per 100,000 people in the general healthy population. However, in
patients with HIV or AIDS, the yearly incidence rate is between 2
and 7 cases per 1,000 people. It’s far more
common in HIV or AIDS patients in sub-Saharan Africa, where people with this
disease have a mortality rate that’s estimated to be 50
to 70 percent.
In many cases, people need to continue
taking fluconazole indefinitely. This is especially true in people who have
AIDS. Taking this medication helps prevent a relapse.