Meningitis - cryptococcal

Definition

Cryptococcal meningitis is an infection of the meninges (the membranes covering the brain and spinal cord) caused by Cryptococcus neoformans.

Causes, incidence, and risk factors

Cryptococcus neoformans is a yeast that is found in soil around the world. Cryptococcal meningitis most often affects people with compromised immune systems. Risk factors include AIDS, lymphoma, and diabetes. It occurs in 5 out of 1 million people.

Symptoms

• Headache
• Fever
• Nausea and vomiting
• Stiff neck
• Sensitivity to light (photophobia)
• Mental status change
• Hallucinations

Signs and tests

In order to diagnose cryptococcal meningitis, a lumbar puncture (spinal tap) must be performed. This test involves taking a sample of fluid from the spinal column (called cerebrospinal fluid or CSF). The following tests on the CSF allow the diagnosis of cryptococcal meningitis:

• CSF stains may show the yeast
• CSF culture grows cryptococcus
• CSF may be positive for cryptococcus antigen

Also, a blood test, the serum cryptococcal antigen test, can be sensitive in diagnosing cryptococcus infection, especially in AIDS patients.

Treatment

Antifungal medications are used to treat this form of meningitis. Intravenous therapy with amphotericin B is the most common treatment. Intrathecal (injection into the spinal cord) medication is sometimes given to people who do not respond to intravenous therapy. An oral medication, fluconazole, in high doses may also be effective against this infection.

Expectations (prognosis)

Maintenance therapy must be given to people with AIDS to prevent relapse.

Complications

Obstructive hydrocephalus is a complication. This occurs when the CSF is not properly drained, resulting in rising pressures on the brain that can cause temporary or permanent brain damage. Amphotericin B can have severely unpleasant side effects.

Calling your health care provider

Call the local emergency number (such as 911) or go to the emergency room if you have symptoms suggestive of meningitis or if you are being treated for meningitis and symptoms worsen.

If you have difficulty breathing or swallowing, paralysis, numbness, or sensory or mental state changes, get to the emergency room as quickly as possible.

Illustrations

Central nervous system

Page Content:

Cryptococcal meningitis ; cryptococcal meningitis