Initial concentration of Staphylococcus epidermidis in simulated pediatric blood cultures correlates with time to positive results with the automated, continuously monitored BACTEC blood culture system.
The relationship of initial concentration of Staphylococcus epidermidis in blood cultures and time to positivity (TTP) in an automated, continuously monitored blood culture system was assessed. Blood and 1 to 1,000 CFU of S. epidermidis per ml in stationary or exponential phase were inoculated in BACTEC Pediatric Plus F bottles and incubated. The TTP was inversely proportional to the initial inoculated concentration. Blood culture bottles with initial bacterial densities of <10 CFU/ml had a TTP of >20 h (upper limit of 95% prediction interval, 20.7 h) and bottles with initial bacterial densities of > or =50 CFU/ml had a TTP of < or =15 h (lower limit of 95% prediction interval, 13.4 h).
Haimi-Cohen
Yishai
Y
Department of Pediatrics, Schneider Children's Hospital, Long Island Jewish Medical Center of the North Shore-Long Island Jewish Health System, New Hyde Park, New York, USA.
Vellozzi
Ernestine M
EM
Rubin
Lorry G
LG
D016470:Bacteremia / Q000382:microbiology*; D002648:Child; D006801:Humans; D013212:Staphylococcus epidermidis / Q000302:isolation & purification*; D013997:Time Factors