Intestinal ultrasound detects an increased diameter and submucosal layer thickness in the appendix of patients with ulcerative colitis compared to healthy controls – a prospective cohort study

Abstract

Summary Background Increasing evidence suggests that appendicectomy as alternative treatment for ulcerative colitis (UC), especially in patients with histopathological appendiceal inflammation. Intestinal ultrasound (IUS) is a non‐invasive diagnostic modality to characterise appendiceal inflammation. Aims To assess appendiceal IUS characteristics in UC patients and compare findings to healthy controls (HC). Methods In this prospective study, appendiceal IUS was performed in consecutive UC patients with active (A; n = 35) or quiescent (Q; n = 30) disease and in HC (n = 30). Transverse appendiceal diameter (TAD) and additional IUS parameters (bowel wall thickness, submucosal layer thickness and colour Doppler signal) were assessed. Results The appendix was visualised in 41/65 UC patients (63.1%; A vs. Q: 23/35 vs. 18/30, p = 0.67) and 18/30 (60%) HC. UC patients had a higher TAD (A: 5.5 mm, Q: 5.0 mm, HC: 4.3 mm; A‐HC p < 0.01; Q‐HC p = 0.01, A‐Q p = ns) and submucosal layer thickness (A: 1.0 mm, Q: 1.0 mm, HC: 0.7 mm; A‐HC p < 0.01, Q‐HC: p = 0.01, A‐Q: p = ns) when compared to HC. A TAD ≥6 mm corresponding to an ultrasonographic suspicion of acute appendicitis was mainly reported in A‐UC patients (A: 43%; Q: 6%; HC: 0%, p = 0.01) and occurred irrespective of disease extent. However, none of the patients had a clinical suspicion of acute appendicitis. Conclusion A TAD ≥6 mm was predominantly seen in A‐UC. TAD was higher in UC patients compared to HC irrespective of disease activity and was characterised by an increased submucosal layer thickness. IUS therefore has the potential to identify UC patients with appendiceal inflammation.

Editorial: routine use of intestinal ultrasound in ulcerative colitis—are we missing the appendix? Authors' reply

“…As IUS has been introduced as a disease monitoring modality in UC and is routinely being used for the diagnosis of acute appendicitis, we aimed to involve IUS in the detection of appendiceal inflammation. We found marginal differences in diameter of the appendix and bowel wall thickness between UC patients and healthy controls, implying a potential role for routine IUS of the appendix in UC patients 7 …”

“…We found marginal differences in diameter of the appendix and bowel wall thickness between UC patients and healthy controls, implying a potential role for routine IUS of the appendix in UC patients. 7 Drs. Suarez and Dr Novak mention absence of assessment of inter-observer agreement as a limitation of our study.…”

“…The authors' declarations of personal and financial interests are unchanged from those in the original article 7 …”

Editorial: routine use of intestinal ultrasound in ulcerative colitis—are we missing the appendix?

“…9 Reijntjes and collaborators explored IUS assessment of the appendix in ambulatory patients with UC in a single-centre prospective cohort study, including a range of UC disease activity. 10 There were 35 patients with active UC, 30 with quiescent UC, and 30 healthy controls (HC); visualisation of the appendix was reported in 63.1% of the UC patients and 60% of the HCs. Interestingly, the transverse appendiceal diameter (TAD) was significantly higher in the patients with UC than HCs regardless of the disease activity (5.5, 5.0, and 4.3 mm, respectively).…”

“…Reijntjes and collaborators explored IUS assessment of the appendix in ambulatory patients with UC in a single‐centre prospective cohort study, including a range of UC disease activity 10 . There were 35 patients with active UC, 30 with quiescent UC, and 30 healthy controls (HC); visualisation of the appendix was reported in 63.1% of the UC patients and 60% of the HCs.…”