The Application Of Metagenomic Next-generation Sequencing In Neonatal Infectious Diseases

Objective:To Analyse the application of Metagenomic Next-generation Sequencing(m NGS)in neonatal infectious diseases.Methods:A total of 65 children who were admitted to the neonatal unit of Shenzhen Children’s Hospital from November 2020 to January 2023 and underwent m NGS technique for blood,alveolar lavage fluid(BALF)or cerebrospinal fluid(CSF)and other related specimens were analysed in a retrospective study.A total of 11 cases without paired sample cultures with m NGS and cases with non-infectious diseases were excluded.The value of m NGS in neonatal infectious diseases was investigated by retrospectively analysing the general clinical data,m NGS results and conventional pathogenic tests in the 54 included cases.Results:1.Among the 54 m NGS samples included,the m NGS positive rate was 63%(34/54),the compliance rate between m NGS positive cases and final clinical diagnosis was55.6%(30/54),12 cases(22.2%)were pathogen positive by conventional pathogenic testing,and 9 cases(16.7%)were positive by both m NGS and conventional pathogenic testing.The rate of positive pathogen detection by m NGS was significantly higher than that of the total conventional test(P < 0.01),while the rate of positive m NGS was also significantly better than that of positive pathogen culture alone(55.6% vs.9.3%,P < 0.01).2.Of the 54 different samples routinely tested for m NGS in this study,44.4%(16/36)were positive for blood specimens,71.4%(10/14)for cerebrospinal fluid specimens,and 100%(4/4)for BALF.The detection rate of CSF pathogens was higher than that in blood,but there was no statistical difference between the two(P > 0.05).3.Of the 54 different samples routinely tested for m NGS in this study,44.4%(16/36)were positive for blood specimens,71.4%(10/14)for cerebrospinal fluid specimens,and 100%(4/4)for BALF.The detection rate of CSF pathogens was higher than that in blood,but there was no statistical difference between the two(P > 0.05).4.Among the 36 blood specimens,there was no significant difference between the positive m NGS test group and the negative m NGS test group in terms of white blood cell count,platelet count,PCT,gestational age and body weight(P>0.05),while there was a statistical difference between CRP and the duration of antibiotic use(P<0.05),and the rate of m NGS positivity decreased after 5 days of antibiotic use.5.Based on 54 m NGS results,treatment regimens were adjusted in 22 children(40.7%),with 13 stopping or downgrading antibiotics,6 upgrading or adjusting antibiotics and 3 receiving antiviral therapy.Conclusions : For neonatal infectious diseases,the positive rate of m NGS testing is significantly better than traditional pathogenic testing;m NGS results are important in guiding clinical treatment and reducing the misuse of antibiotics.