Digital rectal examination compares favourably with conventional water-soluble contrast enema in the assessment of anastomotic healing after low rectal excision: a cohort study

Assessment of healing after low colorectal, colo-anal or ileo-pouch anal anastomosis is routinely performed with a water-soluble contrast enema (WSCE) prior to the reversal of the defunctioning stoma. Interpretation of these radiographs is sometimes difficult and imprecise. As these anastomoses are within the reach of a simple digital rectal examination (DRE), this approach is proposed as an effective and accurate adjunct.

This is a prospective cohort study recruiting patients who had undergone a low colorectal, colo-anal or ileo-pouch anal anastomosis with a diversion stoma. Anastomotic healing was assessed with a DRE in the clinic followed by the conventional WSCE. Anastomotic defects on digital examination and leaks on WSCEs were studied.

There were 195 patients recruited with a total of 202 paired assessments from 182 patients over 45 months. Six months after closure of the study, 174 patients had their stomas reversed. Thirteen examinations with WSCE showed pathology but were normal on digital examination (false positive rate of 6.4% for WSCE). These patients had their stomas reversed with no subsequent problems. Seven patients had an abnormal DRE but had a normal enema study (false negative rate of 3.5% for WSCE). These were large defects with pus and allowed the tip of the examining finger through. Delayed reversal of the stomas in these patients probably avoided continuing pelvic sepsis. The DRE was accurate in all instances except in the detection of a minor fistula in three patients. The sensitivity of the DRE in the detection of anastomotic pathology was 98.4%.

The DRE yields additional and reliable information compared with the conventional water-soluble enema study in the assessment of anastomotic healing prior to stoma closure. In the experienced surgeon, it yielded more useful clinical information than the enema study.