Value of (1-3)-β-D-glucan, Candida mannan and Candida DNA detection in the diagnosis of candidaemia

Abstract

This study determined the value of (1,3)-β-d-glucan (BDG), Candida mannan (MN) and Candida species-specific DNA as surrogates for diagnosis of candidaemia. Thirty-nine patients yielding Candida species in blood cultures were investigated for presence of BDG, MN and Candida species-specific DNA in serum samples. The Candida spp. bloodstream isolates included C. albicans (n = 16), C. tropicalis (n = 10), C. parapsilosis (n = 7), C. glabrata (n = 3) and C. dubliniensis (n = 3). Positivity of the three markers was as follows: Candida DNA for corresponding Candida species, 100%; BDG, 87%; MN, 59%. Despite varying sensitivities of these biomarkers, they provided a useful adjunct to the diagnosis of candidaemia.

Invasive candidiasis: A review of nonculture-based laboratory diagnostic methods

“…[19] Several retrospective and prospective studies have evaluated the utility of mannan detection for the diagnosis of invasive candidiasis in haematological and ICU patients with an overall sensitivity of 58% and specifi city of 93% [ Table 1]. [19][20][21][22] The sensitivity of the test seems to vary with the infecting Candida species, being highest for C. albicans. [21] A positive test has been recorded several days before radiological detection of hepatosplenic candidiasis or positive blood cultures.…”

“…The test has been evaluated, mostly in ICU patients with an overall sensitivity of 77% and specifi city of 85% for subjects with proven or probable invasive fungal infections [ Table 1]. [22][23][24] The test is applied twice weekly and a single positive test is indicative of infection. True positive cases usually show falling BDG titres that eventually become negative in patients responding to antifungal treatment, a trend that is not observed in patients not responding to therapy.…”

“…False positive results due to several conditions, such as haemodialysis, abdominal surgery, treatment with β-lactam antibiotics and concomitant presence of lipopolysaccharide due to Gram-negative bacteremia make its application in clinical setting rather diffi cult. [22][23][24] However, based on excellent negative predictive value of this test (nearly 100%), lack of BDG detection is most useful for excluding invasive fungal infection. [22][23][24] Also, colonization of individuals with Candida spp.…”

“…[22][23][24] However, based on excellent negative predictive value of this test (nearly 100%), lack of BDG detection is most useful for excluding invasive fungal infection. [22][23][24] Also, colonization of individuals with Candida spp. has no apparent effect on the diagnostic performance of the BDG test.…”

“…has no apparent effect on the diagnostic performance of the BDG test. [18,20,22,25] Antibody-based assays Two antibody-based tests are available. An ELISA-based test that detects anti-mannan antibodies which develop in patients when mannan disappears after an episode of candidemia, is marketed, as Platelia Candida Antibody (Bio-Rad Laboratories, Marnes-la-Coquette, France).…”