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

ObjectiveTo explore the application of Metagenomic Next-generation Sequencing(mNGS)in Infectious Diseases of Pediatrics.Method From June 2018 to December 2019,62 children hospitalized in Pediatric Department of Anhui Provincial Hospital were collected,and they performed mNGS of blood,alveolar lavage fluid(BALF)or cerebrospinal fluid(CSF).According to the final diagnosis,samples without paired culture test,confirmed noninfectious disease and unknown disease,failing to pass quaility control of mNGS,and having incomplete medical history were exclude.The general clinical data and the results of mNGS and conventional microbiologic tests of the remaining 49 children were analyzed retrospectively to explore the application of mNGS in pediatric infectious diseases.Result1.Of the 49 samples,the positive rate of mNGS for diagnosing infectious disease was 50.7%,which was higher than that of culture method whose positive rate was 10.2%(p<0.05).Although it was also higher than that of conventional microbiologic tests whose positive rate was 67.3%,there was no difference between the two methods(P>0.05).2.For the detection of adenovirus type 7,the positive rate of mNGS was higher than that of antibody tests in blood(P<0.05).While for the detection of Mycoplasma pneumoniae,there was no significant difference between mNGS and antibody tests in blood(P>0.05).3.There were 5 false positive cases in the results of mNGS.The top-three pathogens detected by mNGS in this study were adenovirus type 7(38.8%),Mycoplasma pneumoniae(30.6%),Haemophilus influenzae(4.1%).Fungal infections were detected in 2 children with serious underlying diseases.Anaerobe infection was detected in a child with multiple pulmonary abscesses.Tuberculosis was suspected Mycobacterium tuberculosis was detected in cerebrospinal fluid by mNGS in a child who was highly suspected as tuberculous meningitis.Conclusion1.mNGS is highly sensitive to the pathogen diagnosis of paediatric infectious diseases,which can provide diagnostic basis for some cases with unknown etiology or clinical suspected diagnosis,and has been an effective supplement diagnostic method currently.2.mNGS has a good detection rate for atypical pathogens,for example adenovirus 7 and mycoplasma,and mixed infection in pediatrics,mixed infection.