AIM: To systematically review all available evidence to describe the incidence, clinical course with management and propose a definition.

METHODS: The databases PubMed, EMBASE and Cochrane databases were searched using with the keywords up to June 2020. Additional manual search was performed and cross-checked for additional references. Data collected included demographics, reason for colonoscopy, time to diagnosis, method of diagnosis (clinical vs imaging) and management outcomes.

RESULTS: A total of nine studies were included in the final systematic review with a total of 339 cases. The time to diagnosis post-colonoscopy ranged from 2 h to 30 d. Clinical presentation for these patients were non-specific including abdominal pain, nausea/vomiting, per rectal bleeding and chills/fever. Majority of the cases were diagnosed based on computed tomography scan. The management for these patients were similar to the usual patients presenting with diverticulitis where most resolve with non-operative intervention (i.e., antibiotics and bowel rest).

METHODS: A retrospective review of all cases of computed tomography-confirmed acute diverticulitis from November 2015 to April 2018 was performed. Data collated included basic demographics, computed tomography scan results (uncomplicated versus complicated diverticulitis), treatment modality (conservative versus intervention), outcomes and follow-up colonoscopy results within 12 months of presentation. The patients were divided into no adenoma (A) and adenoma (B) groups. Visceral fat area (VFA), subcutaneous fat area (SFA) and VFA/SFA ratio (V/S) were measured at L4/L5 level. Statistical analysis was performed to evaluation the association of VFA, SFA, V/S and different thresholds with the risk of adenoma formation.

RESULTS: A total of 169 patients were included in this study (A:B = 123:46). The mean ± standard deviation for VFA was higher in group B (201 ± 87 cm2 versus 176 ± 79 cm2 ) with a trend towards statistical significance (P = 0.08). There was no difference in SFA and V/S in both groups. When the VFA >200 cm2 was analysed, it was associated with a threefold risk of adenoma formation (odds ratio 2.7, 95% confidence interval 1.35-5.50, P = 0.006). Subgroup analysis of gender with VFA, SFA and V/S found that males have a significantly higher VFA in group B (220.0 ± 95.2 cm2 versus 187.3 ± 69.2 cm2 ; P = 0.05).

METHODS: A retrospective analysis of all patients with diverticulitis admitted from November 2015 to April 2018 at a single institution was performed. Data collected included demographics, vital signs, biochemistry results, CT scan findings and management outcomes. The patients were divided into uncomplicated (U) and complicated diverticulitis (C) groups. Visceral fat area (VFA), subcutaneous fat area (SFA) and VFA/SFA ratio (V/S) were measured at L4/L5 level by the radiologist. Statistical analysis was performed to evaluate the association of VFA, SFA, V/S with the parameters in both U and C groups.

RESULTS: 352 patients were included in this study (U:C = 265:87). There was no significant difference in vital signs and biochemistry results in both groups. There was no significant difference in VFA, SFA, V/S ratios in both groups. In patients with V/S ratio > 0.4, they were 5.06 times more likely to undergo emergency intervention (95% CI 1.10-23.45) (p = 0.03). On multivariate analysis, a heart rate > 100 (OR 2.9, 95% CI 1.2-6.7), CRP > 50 (OR 3.4, 95% CI 1.9-6.0), WCC  12 (OR 2.1, 95% CI 1.2-3.6) and V/S ratio > 0.4 (OR 2.8, 95% CI 1.5-5.4) were predictive of complicated diverticulitis.