Purpose: This study investigates whether contrast enema (CE) and flexible endoscopy (FE) should be performed routinely after low anterior resection (LAR) before ileostomy reversal. Additionally, the impact of previous anastomotic leakage (AL) on diagnostic test accuracy (DTA) was assessed.
Methods: This is a retrospective analysis of prospectively collected tertiary care data of two centers. Consecutive rectal cancer patients undergoing LAR with loop ileostomy formation were included. Before ileostomy reversal, all patients were assessed by CE and FE. DTA of FE and CE for asymptomatic AL in patients who had previously suffered from clinically relevant AL (group 1) compared with those without apparent AL after LAR (group 0) were assessed separately.
Results: Two hundred ninety-three patients were included in the analysis, 86 in group 1 and 207 in group 0. Overall sensitivity for detection of asymptomatic AL was 76% (FE) and 60% (CE). Specificity was 100% for both tests. DTA of FE was equal or superior to CE in all subgroups. Prevalence of asymptomatic AL at the time of testing was 1.4% in group 0 and 25.6% in group 1.
Conclusion: Flexible endoscopy is the more accurate diagnostic test for the detection of asymptomatic anastomotic leaks prior to ileostomy reversal. Contrast enema showed no gain of information. In the group without complications after the initial rectal resection, 104 must be tested to find one leak prior to reversal. In those patients, routine diagnostic testing additional to digital rectal examination may be questioned.
Keywords: Asymptomatic anastomotic leak; Contrast enema; Diagnostic test accuracy; Flexible endoscopy; Ileostomy reversal.