Study design
Data were extracted from the medical records of patients admitted to
three university-affiliated tertiary care hospitals in Hunan Province,
China, from January 2010 to August 2021. All three hospitals admitted
both child and adult patients, with a comparable number of patients and
testing techniques, ensuring that there was no difference in ALL
demographic and BSI epidemiological data. A flowchart of patient
selection is shown in Fig.1. Inclusion criteria included diagnosis of
ALL, treatment with chemotherapy, and available blood culture (BC) data.
If the patient had two or more positive BC, the clinical data associated
with the first positive BC during the same hospitalization were
included. Patients who did not meet the inclusion criteria were excluded
from this study. Blood culture samples showing different bacterial
strains within 48h were defined as poly microbial bacteria and were
excluded from the study due to the limited sample volume (N=13), as were
patients who were lost to follow-up (N=8) and blood culture
contamination (N=15). We further excluded patients with a history of
hematopoietic stem cell transplantation (HSCT) (N=11). Finally,
information regarding blood culture-positive patients was obtained, and
the use of antimicrobial therapy was recorded. The primary outcome was
survival or death on day 30 of follow-up.