Sir,I would like to present the first case of ischemic colitis following colonoscopy in a patient with irritable bowel syndrome (IBS). In 2011, a 56-year-old woman was admitted with a 2-year history of recurrent abdominal pain and diarrhea with no systemic diseases. She was diagnosed with IBS after a 10-min colonoscopy (0.5 mg atropine, intramuscularly; no sedation). Three hours later, she developed continuous left lower abdominal pain with tenderness, guarding, and rebound and fresh rectal bleeding. Abdominal X-rays showed no free air in the subdiaphragmatic space. Colonoscopy showed severe diffuse mucosal inflammation of the sigmoid colon suggestive of ischemic colitis. Angiography revealed a normal inferior mesenteric artery. Her condition improved over a few days with conservative treatment. One month later, a colonoscopy showed normal colonic mucosa. The precipitating factors for ischemic colitis following colonoscopy include connective tissue disease or technical difficulties[1] that disrupt small vessel circulation of the large bowel. Our patient was very anxious prior to and during the procedure. We postulate that this psychological stress precipitated the ischemia. Decreased intravascular volume resulting from fasting and colonic preparation[23] may have been a contributory factor. To alleviate colonoscopy-related anxiety, some patients should be counseled before the procedure and perhaps a light sedation to manage pain and stress during the procedure.I hope you can share your advanced experience with us.Yours sincerely,Qiang Zhan