Can Blood Culture Contamination Cloud Fungal Positivity?

Authors : Ali Korhan SIĞ, Gülhadiye AVCU, Basak YİLDİZ ATİKAN, Mustafa GÜNEY

Pages : 61-65

Doi:10.53424/balikesirsbd.1201884

View : 18 | Download : 10

Publication Date : 2023-03-15

Article Type : Research Paper

Abstract :ABSTRACT Objective: Blood culture insert ignore into journalissuearticles values(BC); is gold standard for diagnosis of fungemia. Contamination of BC is a major problem worldwide, since it may delay actual diagnosis. The aim of this study was to evaluate “contaminant” vials with a prolonged incubation insert ignore into journalissuearticles values(max 30 days); with antimicrobial supplemented media to observe any mycological growth. Materials and Methods: Routine BCs obtained patients of Balıkesir Atatürk City Hospital for a year period were included. Render BC System BC12-8 insert ignore into journalissuearticles values(Render Biotech Co. Ltd., Shenzhen, China); were used. Contaminated vials were re-incubated and conventionally inoculated weekly for four weeks total. In case of any growth, identifications were done by PhoenixTM 100 system insert ignore into journalissuearticles values(Becton Dickinson, MA, USA); with cornmeal tween 80 agar insert ignore into journalissuearticles values(RTA Laboratories, Kocaeli, Türkiye);. Antifungal susceptibility testing was applied with CLSI disk diffusion method. Results: 3.9% insert ignore into journalissuearticles values(235 sets and additional 138 vials); of total 6047 BC sets insert ignore into journalissuearticles values(23.06% positive); were contaminated. Only one vial from central venous catheter showed fungal growth within the first week of conventional inoculation insert ignore into journalissuearticles values(>8th day of total incubation);. The isolate was identified as Candida guilliermondii complex and susceptible to caspofungin. Latter set of this patient were positive for the same fungi in the 3rd day of incubation. Conclusion: International guidelines recommend <3% contamination rate. In this study, our single strain was isolated from catheter vial with prolonged incubation and following set was routinely positive for the same fungi. For optimal isolation at least 2 following sets were required and thus, prolonged incubation was not beneficial. It was found that strict following of the rule of “2 following sets\` was enough for optimal isolation of fungemia agent.
Keywords : Candida, invazif fungal enfeksiyonlar, kan dolaşımı enfeksiyonları, kontaminasyon