CT Characteristics Of Acute Pancreatitis With The Pre-existing Fatty Liver And Its Impact On Pancreatitis Severity And Persistent Systemic Inflammatory Response Syndrome

Objective:To study the CT characteristics of acute pancreatitis(AP)associated with pre-existing fatty liver(FL),and the impact of pre-existing FL on the severity of acute pancreatitis(AP)and persistent systemic inflammatory response syndrome(SIRS).Methods:A total of 189 patients with AP were divided into AP with and without pre-existing FL.The CT features,clinical characteristics,the severity of AP,presence of persistent SIRS between the two groups were compared.The severity of AP was assessed by 2012 revised Atlanta classification(RAC),Acute Physiology and Chronic Health Evaluation(APACHE Ⅱ)and Modified CT severity index(MCTSI)score,respectively.Univariate and multivariate analyses were performed to determine the risk factors for predicting SIRS.Diagnostic performances of risk factors were evaluated by receiver operating characteristic(ROC)curve analysis.Results:In the 189 patients,49.7%(94/189)of patients had pre-existing FL.On CT,the AP patients with pre-existing FL were more likely to develop necrosis(23.4%vs 10.5%,p=0.021)and local complications(45.7%vs 29.5%,p=0.025).The prevalence of persistent SIRS was significant higher in the AP patients with pre-existing FL compared with AP patients without pre-existing FL(59.6%vs 27.4%,p<0.001).Multivariate analysis showed that pre-existing FL(OR=2.863,95%CI:1.264-6.486,p=0.012),APACHE Ⅱ≥6(OR=1.334,95%CI:1.117-1.594,p=0.002),and MCTSI ≥4(OR=1.489,95%CI:1.046-2.119,p=0.027)could be an independent risk factor associated with the presence of persistent SIRS respectively.The area under ROC curve of MCISI,APACHE Ⅱ,and pre-existing FL in diagnosing AP patients with presence of persistent SIRS were 0.783,0.703,and 0.664,respectively.Conclusion:Patients with pre-existing FL were more likely to develop necrosis and local complications on CT,present more severe AP,and were prone to development of persistent SIRS.Pre-existing FL can be an independent risk factor in predicting the presence of persistent SIRS in patients with AP.