Rectal-sparing type of ulcerative colitis predicts lack of response to pharmacotherapies

Ulcerative colitis (UC) is known as an immune disorder of the colon that generally involves the rectum, but an atypical distribution of inflamed mucosa has previously been noted in certain subtypes of UC, such as the rectal-sparing type (RST). As noted in a previous report, patients with the RST may be at elevated risk for disease refractoriness, but the clinical significance of RST remains unknown.

UC patients who underwent surgery between January 2010 and April 2015 were included. Patients were classified as having the RST or a non-RST based on colectomy specimens or a pre-operative endoscopy. Possible risk factors for urgent/emergent surgery were analyzed. We specifically determined whether the RST is a significant predictor for urgent/emergent surgery.

In total, 46/482 patients were classified as having the RST. Disease severity was significantly worse in patients with the RST than in other patients (p = 0.02). Urgent/emergent surgery was required for 24/46 patients with the RST, compared with 107/436 non-RST patients (p < 0.01). The overall incidence of urgent/emergent surgery was 131/482. Disease duration < 70.2 months [odds ratio (OR) 2.45], severe disease (OR 87.1), total administered steroid dose < 5000 mg (OR 3.02), daily pre-operative steroid dose ≥ 9 mg (OR 2.59), and the RST (OR 5.59) were identified as independent risk factors for urgent/emergent surgery.

The RST was an independent risk factor for urgent/emergent surgery in our analysis of surgically treated patients with UC.