Current status and therapeutic strategy of acute acalculous cholecystitis: Japanese nationwide survey in the era of the Tokyo guidelines.

Purpose: This study aimed to clarify the incidence, therapeutic modality, and prognosis of acute acalculous cholecystitis and to reveal its optimal treatment strategy.

Methods: As a project study of the Japanese Society for Abdominal Emergency Medicine, we performed a questionnaire survey of demographic data and perioperative outcomes of acute acalculous cholecystitis treated between January 2018 and December 2020 from 42 institutions.

Results: In this study, 432 patients of acute acalculous cholecystitis, which accounts for 7.04% of acute cholecystitis, were collected. According to the Tokyo guidelines severity grade, 167 (38.6%), 202 (46.8%), and 63 (14.6%) cases were classified as Grade I, II, and III, respectively. A total of 11 (2.5%) patients died and myocardial infarction/congestive heart failure was the only independent risk factor for in-hospital death. Cholecystectomy, especially the laparoscopic approach, had more preferable outcomes compared to their counterparts. The Tokyo guidelines flow charts were useful for Grade I and II severity, but in the cases with Grade III, upfront cholecystectomy could be suitable in some patients.

Conclusions: The proportions of severity grade and mortality of acute acalculous cholecystitis were found to be similar to those of acute cholecystitis, and laparoscopic cholecystectomy is recommended as an effective treatment option. (UMIN000047631).