RESUMO
Objective:To establish the method for detecting lower respiratory infections (LRIs) bacterialpathogens using nanopore sequencing, and evaluate the feasibility of this method.Methods:Bronchoalveolar lavage fluid (BALF) samples from 33 patients with LRIs who visited the Department of Respiratory and Critical Care Medicine of Beijing Hospital from July 2019 to September 2020 were collected.Nanopore 16S amplicon sequencing were performed on these samples. In order to evaluate the clinical value of the nanopore sequencing, χ 2 test was used to analyze the pathogen differences between the detection rate and pathogen types results found with using the nanopore 16S sequencing and the results found with bacterial culture. Results:The process and method of nanopore sequencing used in the detection of the LRIs pathogens were established. The pathogen detection rate of the 16S sequencing was higher than that of the traditional bacterial culture (75.8% [25/33], 45.5% [15/33], χ2=5.140, P<0.05). From the 25 positive samples found with nanopore 16S sequencing, 16 pathogens were detected, including Haemophilus parainfluenzae, Haemophilus influenzae, Streptococcus pneumoniae, Streptomonas maltophilia, Acinetobacter baumannii, and Acinetobacter junii, Staphylococcus aureus, Klebsiella pneumoniae, Enterococcus faecalis, Enterococcus gallinarum, Corynebacterium striatum, Mycobacterium paraintracellulare, Serratia marcescens, Achromobacter insuavis, Citrobacter murliniae and Mycoplasma pneumoniae. More than 6 pathogens were tested in clinical culture, including Haemophilus parainfluenzae, Acinetobacter baumannii, Pseudomonas aeruginosa, Staphylococcus aureus, Klebsiella pneumoniae and Streptomonas maltophilia (χ2=7.949, P<0.05). 16S sequencing aligned to species level sequences accounted for 80.0 (60.0, 86.0)% of the genus level. The results obtained by using16S sequencing and bacterial culture were consistent in 11 (33.3%) samples. Conclusions:Nanopore 16S amplicon sequencing can quickly identify pathogenic bacteria from BALF in LRIs patients. Nanopore 16S amplicon sequencing has a high detection rate, it can detect more pathogens than traditional bacterial culture, and it can also identify most bacteria to the species level. This technology is a very promising platform with broad application prospects.
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To investigate whether the laboratory specimens preserved in Beijing Hospital Biobank during a specific period had been contaminated by SARS-Cov-2 through a cross-sectional study, and to establish a retrospective biobank safety screening system. Laboratory specimens were collected from the Department of Respiratory and Critical Care Medicine and the Fever Clinic of Beijing Hospital from November 1, 2019 to January 22, 2020, nucleic acid and serological antibody testing were performed for SARS-CoV-2 in these specimens (including 79 serum, 20 urine, 42 feces and 21 bronchoalveolar lavage fluid specimens). The safety of the stored samples during this period was defined by negative and positive results. Both the nucleic acid test and serological antibody test showed negative for SARS-CoV-2, indicating that these specimens were safely stored in the biobank. High-risk specimens collected in our hospital during the early stage of the COVID-19 outbreak are free of SARS-CoV-2, and a safety screening strategy for the clinical biobank is established to ensure the biosafety of these samples.