Metagenomic next-generation sequencing in detecting pathogens in pediatric oncology patients with suspected bloodstream infections.

BACKGROUND: Studies on mNGS application in pediatric oncology patients, who are at high risk of infection, are quite limited. METHODS: From March 2020 to June 2022, a total of 224 blood samples from 195 pediatric oncology patients who were suspected as bloodstream infections were enrolled in this study. Their clinical and laboratory data were retrospectively reviewed, and the diagnostic performance of mNGS was assessed. RESULTS: Compared to the reference tests, mNGS showed significantly higher sensitivity (89.8% vs 32.5%, P < 0.001) and clinical agreement (76.3% vs 51.3%, P < 0.001) in detecting potential pathogens and distinguishing BSI from non-BSI. Especially, mNGS had an outstanding performance for virus detection, contributing to 100% clinical diagnosed virus. Samples from patients with neutropenia showed higher incidence of bacterial infections (P = 0.035). The most identified bacteria were Escherichia coli, and the overall infections by gram-negative bacteria were significantly more prevalent than those by gram-positive ones (90% vs 10%, P < 0.001). Overall, mNGS had an impact on the antimicrobial regimens' usage in 54.3% of the samples in this study. CONCLUSIONS: mNGS has the advantage of rapid and effective pathogen diagnosis in pediatric oncology patients with suspected BSI, especially for virus. IMPACT: Compared with reference tests, mNGS showed significantly higher sensitivity and clinical agreement in detecting potential pathogens and distinguishing bloodstream infections (BSI) from non-BSI. mNGS is particularly prominent in clinical diagnosed virus detection. The incidence of bacterial infection was higher in patients with neutropenia, and the overall infection rate of Gram-negative bacteria was significantly higher than that of Gram-positive bacteria. mNGS affects the antimicrobial regimens' usage in more than half of patients.