Does pre-incubation period affect detection of Pseudomonas aeruginosa and Acinetobacter baumannii species with automatized Bactec 9120 blood culture system?

Abstract

In this study, the effect of the pre-incubation period on detection of non-fermentative species in blood culture system was investigated. Different concentrations of Pseudomonas aeruginosa and Acinetobacter strains were inoculated into BACTEC-9120 plus+Aerobic/F bottles and incubated for 0, 4, 8, 16 hours at 36°C and then were loaded to the system. Both P.aeruginosa and A.baumannii strains yielded positive signals within 24 hours after loading. In all preincubation periods, as the concentration of P.aeruginosa strains decreased, the detection time was increased. The higher the concentration of A.baumannii strains, is the longer the signalling time as the pre-incubation period is increased, whereas the lower the concentration of A.baumannii strains, is the shorter the signalling time as the preincubation period is increased. Our study indicated that the BACTEC-9120 blood culture system determined non-fermentative bacteria after a pre-incubation time of 16 hours.