Interpretation

The presence of cryptococcal antigen is indicative of cryptococcal CNS disease. If the initial screen is positive, a titer will be performed.

Fungal culture (CSFF) will be set up on all initial positive CSF cryptococcal antigen tests.

Titers are reported as the reciprocal, eg, a titer of 1:80 will be reported as 80.

Low level titers (eg, 1:5) may be falsely positive and should be interpreted with caution, particularly in patients without other evidence of cryptococcal infection. This test should not be used to screen asymptomatic patients.

A negative cryptococcal antigen test does not exclude the diagnosis of cryptococcal meningitis.
Low level positive titers may persist for extended periods of time following appropriate therapy and resolution of infection; monitoring titers should not be used as a test of cure or to guide treatment decisions.