A dedicated fungal culture medium is useful in the diagnosis of fungemia: A retrospective cross-sectional study

Abstract

Background: Mortality for candidemia ranges from 15% to 35%. Current guidelines recommend inoculating blood into three aerobic and three anaerobic blood culture bottles when candidemia is suspected, without mention of a fungal blood culture bottle. Objective: To determine the value of the BACTEC Myco/F Lytic blood culture media in the diagnosis of fungemia. Methods: A two-year retrospective cross-sectional study was performed for patients who had fungemia with submitted BACTEC Plus Aerobic/F (Aer), BACTEC Plus Anaerobic/F (Anaer) or Myco/F Lytic (Myco) blood culture bottles. Results: The detection rate of fungemia was 77.4% in 93 patients with contemporaneously submitted blood culture bottles when limited to only Aer/Anaer culture results. The detection rate improved significantly with the addition of the Myco culture bottle results (p<0.0001). A logistic regression model showed that Myco culture bottle submissions were less useful for patients with appropriate anti-fungal therapy administered within 48 hours [OR = 0.18, 95% CI = (0.06, 0.49), p = 0.001] and those with fungal growth detected within 48 hours [OR = 0.33, 95% CI = (0.12, 0.89), p = 0.001]. Among a subset of patients with concordant blood culture results, those with Myco culture bottles submission allowed earlier fungal detection and speciation by at least one day in 27.5% and 25.0% of the cases respectively. Conclusion: Our study highlights the importance of a dedicated fungal blood culture when fungemia is clinically suspected. Nearly a quarter of fungemias may be missed if a fungal blood culture is not performed. © 2016 Zheng et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.