Current time-to-positivity of blood cultures in the febrile neutropenia: a tool to be used in stewardship de-escalation strategies.
Clin Microbiol Infect. 2018 Aug 07;:
Authors: Puerta-Alcalde P, C C, Suárez-Lledó M, Rodríguez-Núñez O, Morata L, Fehér C, Marco F, Del Río A, Martínez JA, Mensa J, Rovira M, Esteve J, Soriano A, Garcia-Vidal C, Hospital Clínic, Barcelona, Spain
OBJECTIVES: We aimed to describe the current time to positivity (TTP) of blood cultures in onco-hematological patients with febrile neutropenia. We assessed the probability of having multidrug-resistant gram-negative bacilli (MDR-GNB) bloodstream infection (BSI) 24h after cultures were taken, to use this information for antibiotic de-escalation strategies.
METHODS: BSI episodes were prospectively collected (2003-2017). When a patient experienced more than one BSI, only one episode was randomly chosen. Time elapsed from the beginning of incubation to a positive reading was observed; TTP was recorded when the first bottle resulted positive.
RESULTS: Out of the 850 patient-unique episodes, 323 (38%) occurred in acute leukemia, 185 (21.8%) in non-Hodgkin lymphoma and 144 (16.9%) in solid neoplasms (144;16.9%). Coagulase negative staphylococci (CoNS) (225;26.5%), Escherichia coli (207;26.1%), Pseudomonas aeruginosa (136;16%), Enterococcus spp. (81;9.5%) and Klebsiella pneumoniae (67;7.9%), were the most frequent microorganisms isolated. MDR-GNB were documented in 126 (14.8%) episodes. Median TTP was 12 hours (IQR 9-16.5). Within the first 24h, 92.1% blood cultures were positive (783/850). No MDR-GNB was positive over 24h. Of the 67 (7.9%) episodes with a TTP ≥24h, 25 (37.3%) occurred in patients who were already under active antibiotics against the isolated pathogen. Most common isolations with TTP ≥24h were CoNS, candidemia and a group of anaerobic GNB.
CONCLUSIONS: Currently, the vast majority of BSI in onco-hematological patients with febrile neutropenia have a TTP <24h, including all episodes caused by MDR-GNB. Our results support reassessing empiric antibiotic treatment in neutropenic patients at 24h, to apply antibiotic stewardship de-escalation strategies.
PMID: 30096417 [PubMed - as supplied by publisher]