Test for Cryptococcal Meningitis

Cryptococcal meningitis is a fungal infection that affects the meninges located in the brain and spinal cord. It is caused by the fungus Cryptococcus neoformans, which is commonly found in dirt and bird feces. Transmission occurs from inhalation and is not spread through human-to-human contact. Tests available for Cryptocuccus meningitis include cerebral spinal fluid (CSF) culture, CSF stain, Cryptococcus antigen test and imaging studies.

CSF Culture

• The sample obtained from the lumbar puncture (the aspiration of fluid using a needle and aseptic techniques in the lower back) is sent to the laboratory for a CSF culture. In the lab, the sample is placed in a dish with a culture medium and observed to see if any bacteria, fungus or viruses grow on the dish. If abnormal growth is present, the growth is observed under a microscope to determine if it is Cryptococcus neoformans.

CSF Stain

• A CSF stain uses the sample of spinal fluid collected from the lumbar puncture to determine what type of infection is causing the problems. Using a glass slide, the sample is smeared and a stain is applied. A laboratory professional examines the slide under the microscope to determine if the bacteria are gram positive (purple) or gram negative (pink). Gram stains can determine if the individual is positive for Cryptococcus meningitis.

Cryptococcus Antigen Test

• An antigen test for Cryptococcus meningitis can be performed using either CSF or blood serum. The antigen test is performed to locate specific proteins produced by Cryptococcus neoformans. According to the Mayo Clinic, the antigen test is positive in more CSF samples than serum samples.

Imaging Studies

• Health care professionals may suggest a computed tomography (CT) scan or magnetic resonance imaging (MRI) scan of the head if laboratory tests results are positive for Cryptococcus meningitis. These imaging options can detect if lesions are located on the brain and how far the illness has progressed.

Risk Factors

• Individuals with acquired immune deficiency syndrome (AIDS), diabetes and lymphoma are susceptible to contracting Cryptococcal meningitis. These medical conditions affect an individual's immune system, which increases the risk factor for contracting diseases. According to MedlinePlus, Cryptococcus meningitis occurs in 5 out of 1 million people.

Treatment

• The first line of treatment for Cryptococcus meningitis is with amphotericin B, a medication administered through an intravenous line. Amphotericin B can be used in combination with 5-flucytosine. Another medication prescribed to combat this fungal infection is called fluconazole, but this is only effective in high doses. Amphotericin B is known to cause bothersome and/or severe side effects including chills, fever and kidney damage. When Cryptococcus meningitis recurs, the possibility of resistance can occur when long-term treatment is required.