Excluding invasive candidiasis using both Candida germ tube antibody and beta D-glucan tests
October 05 2015
A study evaluating two serological biomarkers in patients receiving treatment for invasive candidiasis (IC) indicates that they may be useful ruling out invasive candidiasis. This is very helpful in antifungal stewardship to stop unecessary or prolonged antifungal treatment in suspected IC cases.
The commercialisation of a Candida albicans indirect chemiluminescent immunoassay for the detection of antibodies against antigens located on the cell wall surface of the mycelium of Candida albicans (CAGTA,Candida albicans germ tube antibody) in human serum or plasma Vircell, Spain) was based on differences in the antigenicity of the two growth phases of Candida albicans with a specific mycelial antigenic component having diagnostic potential. The test appears to discriminate between infection and colonization and it has a high negative predictive value (73%).
Combining the CAGTA assay with the 1-3 ß-D-glucan test (Fungitell, Associates of Cape Cod, USA) in patients on empirical antifungal therapy for presumed candidiasis has shown that serial determination of CAGTA and glucan during empirical antifungal therapy has a high sensitivity (93%) and negative predictive value (91-97%). Serum samples collected by venepuncture on days 0, 3 and 5 after starting empirical antifungal therapy.
If confirmed by other groups, this strategy could be used to discontinue antifungal treatment in at least 30% of patients as a complementary tool in antifungal stewardship programmes (Martinez-Jiménez et al, 2015).
Martinez-Jimenez 2015 Article
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