Clinical characteristics of Gram-negative and Gram-positive bacterial infection in acute cholangitis: a retrospective observational study

BACKGROUND: To investigate the difference in the severity of illness, organ dysfunction, and prognosis of acute cholangitis due to different pathogenic bacterial infection types. METHODS: A retrospective observational study was performed. Patients who met the selection criteria according to blood culture and bile culture results of different pathogenic bacterial were divided into groups. The severity of illness, organ dysfunction, and prognosis of the groups were analyzed and compared comprehensively. RESULTS: A total of 424 patients were included, and no bacterial growth developed in 111 patients (26.2%). Among the 313 patients (73.8%) with bacterial growth, 155 patients had only Gram-negative bacteria cultured (49.5%), 48 patients had only Gram-positive bacteria cultured (15.3%), and 110 patients had both Gram-negative and Gram-positive bacteria cultured (35.1%). The proportion of Grade III patients and the APACHE II and SOFA scores of the mixed Gram-negative and positive group were the highest (p < 0.05); the intensive care unit admission day and hospital stay were longer, and the mortality rate were also higher 20/110 (18.2%) than the other two groups. Regression analysis showed that bacterial growth was an independent risk factor for organ dysfunction. The risks of an increased septic shock, neurological dysfunction, hepatic dysfunction, hematological dysfunction, and respiratory dysfunction in the mixed Gram-negative and positive group were higher than the Gram-negative group (P < 0.05). The Cox proportional hazards regression prompt showed that different culture results were independent risk factors for death. The mixed Gram-negative and positive group had increased hazard ratios and 95% CI of 7.30 (95% CI 1.55 to 34.38) compared with the Gram-negative group. There was no difference between the Gram-negative group and the Gram-positive group in the severity of illness, organ dysfunction, intensive care unit admission day, hospital stay, mortality rate, and risk of death (P > 0.05). CONCLUSIONS: In acute cholangitis, mixed infection with Gram-negative and Gram-positive bacteria was more severe and was associated with a higher risk of death. There were no apparent differences between Gram-negative and Gram-positive bacterial infections. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12879-021-06964-1.