Efficacy and Safety of a Strategy for Reviewing Intravenous Antibiotics for Hospitalized Japanese Patients with Uncomplicated Diverticulitis: A Single-center Observational Study

Abstract

Objective Treatment for uncomplicated diverticulitis (UD) is not well established. We evaluated the strategy of reviewing intravenous antibiotics for hospitalized Japanese patients with UD. Methods Treatment was based on the physician's choice until August 2018; the indications for hospitalization and treatment have been standardized since September 2018. In this study, we monitored the use of intravenous antibiotics administered to patients hospitalized for UD and then reviewed the need for them on hospital day 3. We compared patients' length of antibiotic use, hospital stay, health care cost, and complications via the review strategy from September 2018 to December 2020 and via the previous physicians' choice strategy from January 2016 to August 2018. Results Two hundred and forty-seven patients were admitted to our hospital because of acute colonic diverticulitis from January 2016 to December 2020. After excluding complicated cases, 106 individuals were enrolled during the period of physician's choice; 87 were enrolled when treatment review was employed. There were no significant differences in age, sex, inflammation site, or severity during the first hospital visit. The median duration of antibiotic use was significantly reduced from 5 to 4 days (p=0.0075), with no marked increase in rates of transfer to surgery, mortality, or readmission due to recurrence. A more significant proportion of patients completed 3-day antibiotic treatment with the review strategy than with the physician's choice strategy (6.6% vs. 25.3%, p=0.0004). However, the length of hospital stay and total medical costs did not decrease. Conclusion The strategy of reviewing treatment on day 3 after hospitalization for UD safety reduced the duration of antibiotic use, but the hospital stay and health care costs did not decrease.

Keywords: acute diverticulitis; healthcare costs; hospital stay; intravenous antibiotics; uncomplicated diverticulitis.

Figure 1.

Computed tomography images for stage 1a (a: horizontal view, b: sagittal view) and suspected 1b (c: horizontal view, d: sagittal view) according to the modified Hinchey classification for the severity of acute diverticulitis. In the upper row, bowel wall thickening and pericolic inflammatory reactions with fat stranding pericolic fat (arrowheads, a, b) are observed, indicating stage Ia. In contrast, in the lower row, a small amount of fluid accumulation is noted around the diverticulum, which is confirmed to not be an abscess (arrowheads, c, d), without free air, indicating stage Ib.

Figure 2.

Flow chart of the patient inclusion and exclusion criteria.