Objective:To explore the value of metagenomic next-generation sequencing (mNGS) in the pathogen diagnosis of liver abscess.Methods:A perspective study was performed in 35 hospitalized patients with liver abscess in Department of Emergency Medicine, Zhongshan Hospital, Fudan University from February 2020 to April 2021. Blood samples and abscess drainage fluid samples were detected by routine microbial culture and mNGS. Patients were divided into two groups according to whether they had septic shock or not. SPSS 25.0 was used for statistical analysis.Results:The overall positive rate of mNGS in blood samples and drainage fluid samples was significantly higher than that of routine microbial culture methods (blood: 67.6% vs. 15.2%, P<0.05; Drainage fluid: 100% vs. 55.2%, P<0.05). In 35 patients with liver abscess, 71.4% of the pathogens were Klebsiella pneumoniae. The sequence number of pathogenic pathogens detected by mNGS in abscess drainage fluid samples of patients in the shock group was significantly higher than that in the non-shock group ( P<0.05). Conclusions:The mNGS can quickly and accurately detect the pathogen of liver abscess, which can provide important etiological diagnostic for clinical treatment.

Objective:To analyze the clinical features of patients with pyogenic liver abscess (PLA) and the application of mNGS in PLA, thus to provide reference for clinical diagnosis and treatment.Methods:The demographic and clinical data of 549 patients with liver abscess admitted to Zhongshan Hospital Affiliated to Fudan University from December 2015 to June 2020 were analyzed retrospectively. According to the detection of Klebsiella pneumoniae in 246 patients with positive etiological test results, the patients were divided into two groups: KPLA group and nKPLA group, and clinical characteristics of the two groups were compared. At the same time, the application value of mNGS in PLA was analyzed.Results:Among the 549 patients, the main clinical symptom of PLA was fever ( n= 503, 91.6%) and other clinical symptoms included chills and abdominal pain. Most patients had a single abscess ( n= 464, 84.5%) located in the right lobe ( n = 368, 67.0%), with a size between 5 and 10 cm ( n= 341, 62.1%). A total of 246 patients had positive etiological test results, including 202 KPLA patients which was the main pathogen of liver abscess. The prevalence of diabetes and fatty liver was higher in KPLA patients ( P < 0.05), but there were more culture of liver positive factors in nKPLA patients ( P < 0.001). Among the 109 patients with traditional microbiological results, 92 patients were suspected to KPLA (Klebsiella pneumoniae), of which 14 patients (15.2%) were multidrug resistant (MDR) infection; 17 patients were suspected to nKPLA, of which 10 patients (58.8%) were MDR infection; the incidence of MDR infection in patients with nKPLA was significantly higher than that in patients with KPLA ( P < 0.05). The positive rate of mNGS in plasma was 85.2%, the positive rate of traditional microbial culture in plasma was 14.8%, the positive rate of mNGS in pus was 96.2% and traditional microbial culture in pus was 65.4%. The positive rate of traditional culture was significantly lower than that of mNGS ( P < 0.05). Conclusions:PLA is usually manifested as fever, single and at the right lobe of the liver. Klebsiella pneumoniae is the most common pathogenic bacteria of PLA, which is more common in patients with diabetes and fatty liver, while non-Klebsiella pneumoniae is relatively more common in patients with culture of liver positive factors. The positive detection rate of mNGS is high, which has a unique advantage in pathogen detection.