To investigate clinical risk factors for transmural intestinal necrosis (TIN) in acute mesenteric venous thrombosis (MVT) and establish a predictive model for TIN.

A retrospective analysis was carried out in 102 consecutive patients admitted to Department of Emergency in the First Affiliated Hospital of Sun Yat-sen University with diagnosis of acute MVT during January 2010 and December 2017. These patients were divided into TIN group (35 cases) and non-TIN group (67 cases) based on histopathologic examination of the resected bowel intraoperatively and clinical follow-up. Clinical data including symptoms, vital signs, abdominal physical examination, laboratory results and CT investigations at admission were collected. Multivariable logistic regression analysis was conducted to identify risk factors for TIN of acute MVT, and the receiver operating characteristics (ROC) curve was used to assess the prediction value of the risk factors for TIN.

Of the 102 patients with acute MVT, there were 77 males (75.5%), with a age of (42.9±14.9) years old, and the median follow-up period was 40 months (ranging from 3 to 84 months). A total of 41 patients experienced exploratory laparotomy during first hospitalization and 40 (39.21%) of them underwent intestinal resection, whereas only 31 patients were diagnosed with TIN by histopathologic examination of the resected bowel, and the rest 9 patients were identified to have mucosal necrosis without TIN. 61 patients received conservative treatment during first hospitalization, 2 of whom were unable to undergo surgery as the extensive intestinal necrosis and died soon, whereas 2 patients failed to respond to anticoagulation therapy and underwent intestinal resection within 3 months of follow-up period. A total of 62 patients (60.8%) were found to have secondary etiologies. Multivariable analysis using binary Logistic regression analysis showed that the significant independent predictors for TIN in patients with acute MVT were WBC count >14.87×10⁹/L (OR=10.574, 95% CI: 1.762-63.468; P=0.010), TT≤ 15.9 s (OR=7.880, 95% CI: 1.302-47.696; P=0.025) and a medium amount of ascites on CT scan (OR=11.730, 95% CI: 1.747-78.753; P=0.011). The rate of TIN in patients with acute MVT with no predictive factor were 0, 4.76%, 54.55% and 100.00% in patients with 0, 1, 2, and 3 factors, respectively. The predictive model according to these risk factors revealed an excellent predictive performance with an area under the ROC curve for the diagnosis of TIN in patients with acute MVT was 0.928 (95% CI: 0.848-0.974).

WBC count >14.87×10⁹/L, TT≤15.9 s and a medium amount of ascites on CT scan are the significantly independent predictors for TIN in patients with MVT. Close monitoring of these risk factors may help avoid unnecessary surgery and bowel resection, and reduce the delayed operative treatment of TIN.