Cryptococcal Ag

Keywords: Cryptococcal antigen

Specimen:

5-10 mL blood or 2 mL CSF in plain tube.

Method:

Latex agglutination.

Application:

Diagnosis of Cryptococcal infection; monitoring response to therapy.

Interpretation:

Positive in both serum and CSF in > 95% of patients with cryptococcal meningitis; a negative result does not exclude infection.

Antigen levels decrease with effective therapy, but there is a poor correlation between antigen levels and disease activity in HIV positive patients.

Serial testing to monitor response to therapy is not of value in this patient group.

Reference:

Mitchell T and Perfect J. Clin Microbiol Rev 1995; 8: 515-548.