Abstract: Objective To determine the influencing factors of spontaneous bacterial peritonitis (SBP) caused by Gram-positive and Gram-negative bacterial infections. Methods From October 2015 to February 2020, 116 patients with hepatitis B cirrhosis complicated with SBP were admitted to our hospital, including 92 males and 24 females. The average age was (57.6±7.2). According to the results of ascites culture, they were divided into Gram-positive and Gram-negative groups. The diagnosis of hepatitis B and SBP met the requirements. The flora characteristics were compared between the Gram-positive and Gram-negative groups, and the influencing factors of Gram-positive bacterial infection in patients with hepatitis B cirrhosis complicated with SBP were further analyzed. Results Among 16 patients with hepatitis B cirrhosis complicated with SBP, 41 cases (35.3%) were infected by Gram-positive bacteria and 75 cases (64.7%) were by Gram-negative bacteria. The former included 16 cases of Enterococcus (13.8%), 13 cases of Staphylococcus aureus (11.2%), 10 cases of Aeromonas (8.6%) and 2 cases of Streptococcus (1.7%). The latter included 40 cases of Escherichia coli (34.5%), 27 cases of Klebsiella pneumoniae (23.3%), 6 cases of Pseudomonas aeruginosa (5.2%), and 2 cases of Providence reyi (1.7%). In Gram-positive groups, Child-Pugh score, MELD score and SOFA score of gram-positive group were (7.9±1.8), (18.0±5.8) and (4.7±1.8), respectively, which were significantly lower than those in gram-negative group [(9.7±2.1), (22.4±7.0) and (6.7±2.1), with statistically significant difference (P<0.05). Furthermore, 20 cases (48.8%) and 18 cases (24.0%) in Gram-positive and Gram-negative groups received antimicrobial therapy within one month, respectively, with statistically significant difference (P<0.05). There was no significant difference in age, sex, BMI, serology, ascites index and 28-day mortality between the two groups (P>0.05). By multivariate analysis, antimicrobial therapy within one month and SOFA score were the independent influencing factors of SBP Gram-positive bacterial infection (P<0.05). Conclusion Similarly to the previous studies, the SBP caused by Gram-positive bacteria in patients with liver cirrhosis was significantly related to antimicrobial therapy within one month before SBP diagnosis and low SOFA score. Therefore, it is necessary to consider these factors when diagnosing and treating patients with cirrhosis and SBP.

Key words: Hepatitis B cirrhosis, Spontaneous bacterial peritonitis, Gram-positive bacteria, Child-Pugh classification