Validation of TG13 severity grading in acute cholecystitis: Japan‐Taiwan collaborative study for acute cholecystitis

Background The collaborative multicenter retrospective study of acute cholecystitis (AC) was performed in Japan and Taiwan. The aim for this study was evaluation of the clinical value of TG13 severity grading for AC. Method The study was designed as an international multicenter retrospective study of AC from 2011 to 2013. Based on the data, we investigated the TG13 severity grading by analyzing the correlations between grade and prognosis, surgical procedures, histopathology, and organ dysfunction and prognosis. Results An investigation revealed that 30‐day overall mortality rate was 1.1% for Grade I, 0.8% for Grade II, 5.4% for Grade III. The mortality rate for Grade III was significantly higher than lower grades (P