Cryptococcal antigen (CrAg) assays
Cryptococcosis is an infection caused by the invasive fungus Cryptococcus.
Cryptococcosis is an opportunistic infection caused by fungi of the genus Cryptococcus. It is commonly associated with immunosuppressive individuals while being rare in healthy individuals. The two species of Cryptococcus that are commonly associated with infections in humans are Cryptococcus neoformans and Cryptococcus gatti.
Individuals with an impaired cell mediated immune system are at particular risk of infection. The incidence is rising due to the increase in the number of patients who are:
On Chemotherapy
with HIV infection
On anti-rejection drugs following transplantation.
Cryptococcus fungal infections can remain undetected until symptoms become apparent. Then they are very difficult to treat.
Applications
Cryptococcosis is especially prevalent among those infected with HIV who have developed AIDS. Cryptococcal meningitis is one of the most common opportunistic infections among these patients, estimating more than 220,000 cases and 181,000 deaths worldwide each year. Early detection and treatment of infection are key to reducing the mortality associated with this disease.
Cryptococcal Antigen Lateral Flow Assay
The IMMY CrAg® LFA (Cryptococcal Antigen Lateral Flow Assay) is the first and only immunochromatographic dipstick assay for the qualitative and semi-quantitative detection of the cryptococcal capsular antigen in serum, plasma, whole blood and cerebrospinal fluid (CSF).
Latex Agglutination Assays
The LATEX-CRYPTO ANTIGEN TEST is a latex agglutination test for the semi-quantitative detection of the capsular polysaccharide antigens of Cryptococcus neoformans in serum and cerebrospinal fluid (CSF).
Benefits
Revolutionising Crytococcal Antigen Testing
Delivering excellent sensitivity across all serotypes of Cryptococcus, IMMY CrAg® LFA has revolutionised cryptococcal antigen testing.
Detects all four CrAg serotypes with improved sensitivity for C. gattii infections (Serotype C)
5 easy steps with no equipment required and no specimen pretreatment
Quick and easy to run, taking only 10 minutes
Less than one minute hands-on time
Easily scaled up to handle multiple samples meeting the needs of both small and large volume laboratories
Allows for titre determination (semi-quantitation) up to five times more sensitive than other cryptococcal antigen diagnostics available
CrAg Method Sensitivity Comparison
Serotype sensitivity (ng CrAg/ml)*
| Immunoassay Method | Serotype A | Serotype B | Serotype C | Serotype D | |||||
|---|---|---|---|---|---|---|---|---|---|
| Immunoassay Method | Serotype A | Serotype B | Serotype C | Serotype D | IMMY LFA Strip | 1 | 1 | 9 | 8 |
| Immunoassay Method | Serotype A | Serotype B | Serotype C | Serotype D | IMMY Latex | 28 | 47 | 380 | 62 |
| Immunoassay Method | Serotype A | Serotype B | Serotype C | Serotype D | Meridian CALAS Latex | 19 | 37 | 940 | 54 |
| Immunoassay Method | Serotype A | Serotype B | Serotype C | Serotype D | Inverness Latex | 38 | 64 | 1600 | 50 |
| Immunoassay Method | Serotype A | Serotype B | Serotype C | Serotype D | Meridian Premier ELISA | 28 | 23 | >2000 | 770 |
*Clin Vaccine Immunol. 2011 Aug;18(8):1292-6. Epub 2011 Jun 22 | |||||||||
Publications
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How to stop 'crypto,' a deadly disease so neglected it's not even on the 'neglected' list
Public Radio International article
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Cryptococcal Meningitis Diagnostics and Screening in the Era of Point-of-Care Laboratory Testing
Rajasingham et al.
J Clin Microbiol. 2019 Jan 2;57(1). -
Point-of-Care Diagnosis and Prognostication of Cryptococcal Meningitis With the Cryptococcal Antigen Lateral Flow Assay on Cerebrospinal Fluid
Kabanda etal.
Clin Infect Dis. 2014;58(1):113–116. -
CrAg lateral flow assay for cryptococcosis.
Kozel TR, Bauman SK.
Expert Opin Med Diagn. 2012;6(3):245–251.
