Study population
The flow chart of the study group selection process is presented in Figure 1. The inclusion criteria were patients with severe hepatitis flare of HBV-related compensated liver cirrhosis and did not fulfilled the diagnostic criteria of ACLF on admission. 364 hospitalized patients at the Affiliated Hospital of Zunyi Medical University from January 2011 to March 2020 were included. 127 patients were excluded by the exclusion criteria, which included coinfection with hepatitis A, C, D, or E viruses; coexistence with other liver diseases including alcoholic liver disease, hepatocellular carcinoma, drug-induced hepatitis, autoimmune hepatitis, Wilson disease, or serious diseases involving other organ systems; pregnancy; patients who had been treated with chemotherapy or had nucleot(s)ide analogues withdrawal within 1 year. The patients with using of proton pump inhibitors before occurring of BI were excluded 16. A total of 237 patients were finally included in this study.
Diagnostic criteria of severe hepatitis flare, ACLF, liver cirrhosis and BI
Severe hepatitis flare was defined as alanine aminotransferase (ALT) >5× the upper limit of normal (ULN, 200 IU/L) and total bilirubin (TBil) ≥5×ULN (85 μmol/L) or prothrombin activity (PTA) 40%-60% in patients with HBV-related compensated liver cirrhosis.
ACLF was diagnosed as the criteria proposed by Asian Pacific Association for the Study of the Liver (APASL), which includes the recent development of jaundice (TBil ≥5×ULN) and coagulopathy (PTA<40% or international normalized ratio [INR] ≥1.5), complicated within 4 weeks by ascites and/or encephalopathy in a patient with previously diagnosed or undiagnosed chronic liver disease 17.
The diagnosis of cirrhosis was based on previous liver biopsy findings or a composite of clinical signs and findings provided by laboratory tests, endoscopy, radiologic imaging, and fibroscanning. HD was defined as development of ascites, bleeding due to portal hypertensive sources, or overt hepatic encephalopathy18. Patients with no previous decompensation were included in this study as compensated liver cirrhosis.
BIs were diagnosed as per the following criteria 19: (1) spontaneous bacterial peritonitis (SBP): ascitic fluid polymorphonuclear cells >250/mL or positive ascitic fluid cultures; (2) bacteremia: positive blood cultures without a source of infection; (3) pneumonia: new pulmonary infiltrate with fever (>38°C) with any respiratory symptoms (e.g., cough, sputum, dyspnea) or any findings on auscultation (rales or crepitation), or white blood cell (WBC) counts >10×109/L or <4×109/L; (4) urinary tract infection (UTI): more than 10 leucocytes per high power field in urine and positive urine cultures or significant leucocyte count per field without positive cultures; and (5) other bacterial infections, including skin infections, intra-abdominal infections, and infections of unknown origin. In patients with suspected respiratory infections and infections with unknown origin, the IgM antibody to Influenza virus A and B, Parainfluenza virus, Adenovirus, Mycoplasma and Chlamydia and DNA of Epstein-Barr virus and Cytomegalovirus were detected to exclude the infections induced by these pathogens. In addition, the diagnosis of BI was made by two independent investigators. If there was any discrepancy between the two investigators, a senior investigator was requested to make decision.
Candidate predictor variables and treatment schedule
The demographics, clinical and laboratory variables, and imaging findings of patients were retrospectively collected. In addition, liver disease severity was assessed using the Model for End-Stage Liver Disease (MELD) -Na score, Child-turcotte-pugh (CTP) score and chronic liver failure-sequentail organ failure assessment (CLIF-SOFA) score 6. Standard medical care including antiviral therapy with lamivudine, entecavir, or telbivudine was administered to all patients according to HBV replication levels and patient willingness. Patients with BI were treated with antibiotic therapy following current recommendations was initiated20.
The end point of study was the development of ACLF within 28 days after admission. The BIs and HD occurring before the development of ACLF were recorded. The protocol conformed to the provisions of the Declaration of Helsinki and was approved by the Human Ethical Committee of the Affiliated Hospital of Zunyi Medical University.
Statistical analysis
Statistical analyses were performed using SPSS version 19.0 (IBM Corp., Armonk, NY, USA). Patient characteristics were compared between patients with and without progression to ACLF and BIs using c2 tests for categorical variables, t tests for variables with normal distribution, and Mann-Whitney U tests for variables with an abnormal distribution. Continuous variables are summarized as mean ± standard deviation (SD) or median (interquartile range, IQR), respectively. Categorical variables are displayed as counts or percentages (%). Logistic regression analysis was used for univariate and multivariate analyses to identify the risk factors associated with progression to BI and ACLF. P < 0.05 was considered statistically significant.