Prognostic role of time to positivity of blood culture in children with Pseudomonas aeruginosa bacteremia.

Abstract Background Pseudomonas aeruginosa ( P. aeruginosa ) is a major Gram-negative pathogen, which has been reported to result in high mortality. We aim to investigate the prognostic value and optimum cut-off point of time-to-positivity (TTP) of blood culture in children with P. aeruginosa bacteremia. Methods From August 2014 to November 2018, we enrolled the inpatients with P. aeruginosa bacteremia in a 1500-bed tertiary teaching hospital in Chongqing, China retrospectively. 52 case were analyzed. Receiver operating characteristic (ROC) analysis was used to determine the optimum cut-off point of TTP, and logistic regression were employed to explore the risk factors for in-hospital mortality and septic shock. Results Totally, 52 children with P. aeruginosa bacteremia were enrolled. The standard cut-off point of TTP was18 hours. Early TTP (≤18 hours) group patients had remarkably higher in-hospital mortality (42.9% vs 9.7%, P=0.014), higher incidence of septic shock (52.4% vs 12.9%, P=0.06), higher Pitt bacteremia scores [3.00 (1.00-5.00) vs 1.00 (1.00-4.00), P=0.046] and more intensive care unit admission (61.9% vs 22.6%, P=0.008) when compared with late TTP (>18 hours) groups. Multivariate analysis indicated TTP ≤18 h, Pitt bacteremia scores ≥4 were the independent risk factors for in-hospital mortality (OR 5.88, 95%CI 1.21-21.96, P=0.035; OR 4.95, 95%CI 1.26-27.50, P=0.024; respectively). The study also revealed that the independent risk factors for septic shock were as follows: TTP≤18h, Pitt bacteremia scores≥4 and hypoalbuminemia (OR 6.30, 95%CI 1.18-33.77, P=0.032; OR 8.15, 95%CI 1.15-42.43, P=0.014; OR 6.46, 95% CI 1.19-33.19 P=0.031; respectively). Conclusions Early TTP (≤18 hours) appeared to be associated with worse outcomes for P. aeruginosa bacteremia children.