[Single Center Clinical Analysis of Bloodstream Infection Pathogens in Children with Acute Leukemia]

To investigate the clinical features, distribution of pathogenic bacteria, and drug resistance of bloodstream infection in children with acute leukemia.

Clinical data of 93 blood culture-positive children with acute leukemia from January 2015 to December 2019 in Department of Pediatrics, The Second Hospital of Anhui Medical University were analyzed retrospectively.

In these 93 cases, 78 cases were in the period of neutrophil deficiency. There were 54 Gram-negative bacteria (G^-) (58.1%) found through blood culture, and the top 4 strains were Escherichia coli (15.1%), Klebsiella pneumoniae (13.9%), Pseudomonas aeruginosa (6.5%), and Enterobacter cloacae (6.5%). There were 39 Gram-positive bacteria (G⁺) (41.9%) detected, and the top 4 strains were Staphylococcus epidermidis (10.8%), Streptococcus pneumoniae (6.5%), Staphylococcus hemolyticus (5.4%), and Staphylococcus human (5.4%). Among 74 strains of pathogenic bacteria from acute lymphoblastic leukemia (ALL) children, there were 29 strains of G⁺ bacteria (39.2%) and 45 strains of G^- bacteria (60.8%). While in 19 strains from acute myeloblastic leukemia (AML) patients, G^- bacteria accounted for 47.4% and G⁺ bacteria accounted for 52.6%. In 15 ALL children without neutropenia, G⁺ bacteria made up the majority of the strains (66.7%). In the 93 strains of pathogenic bacteria, 13 (13.9%) strains were multidrug-resistant. Among them, extended-spectrum β-lactamases accounted for 42.9%, carbapenemase-resistant enzyme Klebsiella pneumoniae 15.4%, and carbapenemase-resistant enzyme Enterobacter cloacae strains 33.3%, which were detected from G^- bacteria. While, 13.3% of methicillin-resistant coagulase-negative Staphylococci accounted for 13.3% detected from G⁺ bacteria, but linezolid, vancomycin, teicoplanin Staphylococcus and Enterococcus resistant were not found. The average procalcitonin (PCT) value of G^- bacteria infection was (11.02±20.282) ng/ml, while in G⁺ infection it was (1.81±4.911) ng/ml, the difference was statistically significant (P<0.05). The mean value of C-reactive protein (CRP) in G^- infection was (76.33±69.946) mg/L, and that in G⁺ infection was (38.34±57.951) mg/L. The prognosis of active treatment was good, and only one case died of septic shock complicated with disseminated intravascular coagulation (DIC) and gastrointestinal bleeding caused by carbapenemase-resistant enzyme enterobacteriaceae.

G^- is the major bacteria in acute leukemia children with bloodstream infection, but the distribution of ALL and AML strains is different. G^- bacteria dominates in ALL, while G⁺ bacteria and G^- bacteria are equally distributed in AML. Non-agranulocytosis accompanied by bloodstream infections is dominant by G⁺ bacteria. The mean value of PCT and CRP are significantly higher in G^- bacteria infection than in G⁺ bacteria.