Right colonic diverticulitis in Caucasians: presentation and outcomes versus left-sided disease

To compare clinical features, computed tomography (CT) findings, and outcomes of right vs. left colonic diverticulitis (CD) in Caucasians.

This single-center retrospective case-control study of patients seen between July 2005 and February 2013 included 30 consecutive cases of right CD and 70 controls taken at random from a consecutive cohort of patients with left CD. The final diagnosis was established by consensus between a gastrointestinal surgeon and a gastrointestinal radiologist. Clinical features, treatment, and follow-up data were collected. Two radiologists blinded to patient data reached a consensus about multiple CT criteria. Cases and controls were compared using appropriate statistical tests, and odds ratios (ORs) associated with clinically meaningful variables were computed using univariate logistic regression.

Median age was significantly lower in cases than in controls (48.5 years [IQR, 31-61] vs. 63.5 years [54-75], P < 0.0001). A body mass index <20 kg/m² compared to >30 kg/m² was associated with a higher risk of right than of left CD (OR 22.7, 95% confidence interval [95% CI], 2.6-200, P = 0.005). Compared to controls, cases more often had CT evidence of focal diverticular inflammation (86.7% [26/30] vs. 50% [35/70], P = 0.0006) and noncircumferential (≤180°) colonic wall thickening (66.7% [20/30] vs. 20% [14/70], P < 0.001). Complications were less common in the cases (6.7% [2/30] vs. 25.7% [18/70] than in controls, P = 0.03).

In Caucasians, right CD occurs in younger and thinner patients and carries a lower risk of complications compared to left CD. Focal diverticular inflammation by CT is more common in right than in left CD.