Management and long-term outcomes of acute right colonic diverticulitis and risk factors of recurrence

This retrospective study involved a cohort of 162 patients (age ≥ 18 years), treated at the Department of General Surgery, Tongren Hospital, Shanghai Jiao Tong University School of Medicine from December 2015 to December 2020. Acute RCD was defined according to previous studies, as the presence of colonic diverticular disease with localized colonic wall thickening and/or stranding of pericolonic fat [1, 11, 18]. A diagnosis of acute RCD was confirmed by abdominal ultrasonography (US), computed tomography (CT), colonoscopy, and further clinical assessments. Furthermore, acute RCD was also diagnosed by postoperative histological examination. Patients with missing data on length of stay or disposition on discharge were excluded from the study, as were patients with a concomitant diagnosis of colorectal cancer, inflammatory bowel disease (IBD), bowel ischemia, acute appendicitis and gastrointestinal hemorrhage. Other exclusion criteria included hemodynamic instability, multi-organ failure, and American Society of Anesthesiologists (ASA) classification IV or higher. The clinical data, including demographic information, medical history, symptoms, morbidity, mortality, and follow-up information were collected and retrospectively analyzed. The study protocol was approved by the Institutional Review Board of Tongren Hospital, Shanghai Jiao Tong University School of Medicine. Informed consent was waived due to the retrospective nature of this study and data were analyzed anonymously.

Each patient received conservative or surgical treatment, based on his or her evaluation and the severity of the acute RCD. Conservative treatment included bowel rest and intravenous antibiotics, followed by a week of oral antibiotics after discharge. When the patient has no fever and abdominal pain, oral intake was resumed. Failure of conservative treatment led to surgical treatment. Emergent surgery was executed within 12 h after admission, or failure of conservative treatment led to emergent surgery, elective surgery for patients suffering from recurrent diverticulitis. Surgical procedures including appendectomy with postoperative antibiotic treatment, diverticulectomy, diverticulectomy with appendectomy, and right hemicolectomy/ileocecal resection.

Patients were categorized according to the Hinchey classification by evaluating their radiological images [19]. The classifications were Grade I: inflamed diverticulum; Grade II: inflamed mass; Grade III: localized abscess/fistula; and Grade IV: perforation/ruptured abscess with generalized peritonitis (Fig. 1). Grade I signifies uncomplicated diverticulitis, which involves thickening of the colon wall and pericolonic inflammatory changes, whereas Grades II, III, and IV indicate complicated diverticulitis, which also includes abscess, peritonitis, obstruction, and/or fistulae. Mortality was defined as in-hospital death.

All cases were followed up for at least 12 months. Outpatient visits were executed at 1 week, 1 month, 6 months, and 12 months after discharge. Telephone follow-up was conducted every six months after 12 months. During this follow-up period, if the patient has signs or symptoms indicating the recurrence of RCD, the patient will be recalled for CT scan. The primary endpoint was recurrence, based on CT evidence of recurrent RCD at 1 month after discharge. Recurrence within 1 month of discharge was regarded as treatment failure [13]. The secondary endpoints included treatment success, death and complications. Complications were classified using the Clavien-Dindo classification [20], which is based on the therapy required to treat them.