Can bacteraemia lead to false positive results in 1,3-beta-D-glucan test? Analysis of 83 bacteraemia episodes in high-risk patients for invasive fungal infections

Abstract

Background: Although bacteraemia has been reported to be related to false positive results in the 1,3-beta-D-glucan (BDG) test, the evidence for this interaction is limited.

Aims: To investigate the association between bacteraemia and the BDG test.

Methods: Records of the Infection Control Committee were reviewed to identify bacteraemia in patients who were hospitalized in the haematology ward and stem cell transplantation unit. Patients who had undergone the BDG test at least once within 5 days of a positive blood culture were included in the study. BDG levels in the sera were assayed using the Fungitell kit (Associates of Cape Cod, East Falmouth, MA) according to the manufacturer's specifications. The cutoff for BDG positivity was 80 pg/mL.

Results: Eighty-three bacteraemic episodes were identified in 71 patients. BDG positivity was detected in 14 patients with bacteraemia, and only 1 patient with Escherichia coli bacteraemia had high BDG levels (over 80 pg/mL) despite having no evidence of invasive fungal infection (IFI).

Conclusions: Our study suggests that the cross-reactivity of the BDG test with a concomitant or recent bacteraemia is a very rare condition. Patients with risk factors for IFI should be evaluated cautiously when a positive BDG test is reported.