Used to aid in the diagnosis of cryptococcal disease.

The CrAg Lateral Flow Assay is an immunochromatographic test system for the qualitative or semi-quantitative detection of the capsular polysaccharide antigens of Cryptococcus species complex (Cryptococcus neoformans and Cryptococcus gattii) in CSF.



Cryptococcal antigen in the CSF of untreated patients indicates active disease in non-AIDS patients.  In non-AIDS patients, declining titers indicate a positive response to chemotherapy in the treated patient and failure of titers to decline indicates inadequate therapy.  Occasionally, however, low titers may persist for an indefinite period in the presence of nonviable fungus.  For AIDS patients there is much less information on the type of antigen response to successful or inadequate therapy making interpretation of changes in titer difficult.



While CSF titers of 1:4 or less are presumptive evidence of central nervous system infection by C. neoformans, additional follow-up and culture are strongly recommended.  CSF titers of 1:8 or greater from patients with meningitis strongly suggest infection by C. neoformans.  However, diagnosis should be confirmed by identification of the organism from culture or by microscopic examination of the specimen.



Cryptococcal antigen titers of positive specimens are reported.  Specimens are titered to an endpoint up to 1:2560.  Consult the Infectious Diseases Service if there is a need to titer beyond 1:2560.

Lateral Flow - a rapid and sensitive screen to aid in the diagnosis of cryptococcal disease.  
Refer to "CRYPTOCOCCAL ANTIGEN SERUM" for additional information.
Includes "CULTURE FUNGUS OTHER SOURCE" at additional charges when sufficient volume received and patient is immunocompromised or immunocompetent with abnormal CSF WBC count (>5 WBC per cubic mm).