Recognizing Barotrauma during Colonoscopy: A Cat Scratch Colon.

Abstract

A 75-year-old woman underwent an elective colonoscopy for chronic abdominal pain and anemia. She had a history of hypertension, hypothyroidism, and anxiety and had been taking losartan, hydrochlorothiazide, and thyrotoxin for 6 years. The patient did not have a history of collagenous disease or cholestasis and denied having diarrhea, bleeding, weight loss, or family history of cancer colon. Physical examination of the abdomen showed no masses, pain, or tenderness. Routine blood tests revealed a white blood cell count of 7,810/mm2, a hemoglobin level of 10.6 g/dL, a platelet count of 327,000/mm2, a serum creatinine level of 1.02 mg/dL, TSH 1.34 μIU/mL, and ferritin 365.1 ng/mL. The colonoscopy revealed reddish, flat, bright streaks with sharp boundaries and dotted surfaces suggesting small bleeding points located in the ascending colon and cecum close to the ileocecal valve. The streaks did not follow the arrangement of submucosal vessels and were distributed in parallel and perpendicular to each other (Fig. 1). The remaining cecum, colon, and rectum presented normal vascular and mucous patterns. The colonoscopy, which had been easy up to this point, was ended after the diagnosis of cat scratch colon because of the risk of barotrauma and perforation [1]. McDonnel et al. [2] first described “Cat scratch” in 2007 and reported an 81% prevalence in females that was related to barotrauma from overdistension. Although this finding has no clinical implications, it may be a useful sign to prevent colonic perforation during colonoscopy. Cat scratch is associated with the following conditions that lead to a less complacent colon or bleeding: collagenous colitis, a chronic inflammatory bowel disease that causes mucosal atrophy and impaired colonic compliance [2]; ischemic colitis because intestinal ischemia creates an edematous and fragile mucosa [3]; chronic cholestasis, which can impair absorption of vitamins K and A and cause bleeding predisposition and damage to the intestinal mucosal barrier integrity [4]; and chronic use of anti-inflammatory drugs that can lead to gastrointestinal toxicity and mucosal injury in the form of erosions and ulcers [5]. It is widely accepted by most authors that the marks are caused by intramural bleeding associated with intestinal distension that is caused by insufflated air during the colo-