Right-Sided Ischemic Colitis Following Routine Colonoscopy Mimicking Post-Polypectomy Bleeding: A Case Report

Inside the human body, the colon is a long, muscular tube that absorbs water and nutrients from waste before it leaves the body. To see inside this tube clearly, doctors often perform a procedure called a colonoscopy, where a flexible camera is guided through the entire length of the organ. This allows them to spot and remove small growths called polyps before they can become dangerous. While this is a routine and generally safe procedure, the body sometimes reacts in unexpected ways. One such reaction is ischemic colitis, a condition where blood flow to a section of the colon is temporarily reduced, causing the tissue to become inflamed and damaged. This usually happens in older adults with heart or blood vessel problems, but it can occur in anyone under specific circumstances. Understanding how this happens in healthy, younger people is important because the symptoms can look exactly like a common complication, leading doctors to treat the wrong problem.

A recent case report details the experience of a 53-year-old woman who underwent a standard colonoscopy at a clinic. She was in excellent health, with no history of heart disease, high blood pressure, or other medical issues. During the procedure, the doctor found a small, 8-millimeter growth near the beginning of her large intestine, known as the cecum. Using a cold snare, a wire loop that cuts without heat, the doctor removed the polyp and placed a tiny metal clip to seal the spot. The woman was sent home just 30 minutes later, feeling fine. However, by that afternoon, she began to feel pain in her belly and noticed a small amount of bright red blood in her stool. By the next day, both the pain and the bleeding had gotten worse.

When she returned to the hospital, her vital signs showed her heart was beating faster than usual, a sign her body was under stress. Doctors initially suspected that the metal clip had come loose or that the spot where the polyp was removed was bleeding. To check this, they performed a second colonoscopy, looking closely at the area where the polyp had been taken out. They found that the clip was still in place and the spot was perfectly clean, with no active bleeding. This ruled out the most obvious cause of her symptoms. Instead, as the camera moved further up into the right side of her colon, the doctors saw something new. The lining of the ascending colon, which had looked completely normal during the first exam, was now swollen, red, and covered in small bruises and ulcers. These changes were confined to a specific segment of the bowel, a pattern that pointed directly to a lack of blood flow rather than an infection or a reaction to the cleaning solution used before the procedure.

The medical team diagnosed her with right-sided ischemic colitis, a condition where a section of the colon is starved of oxygen. Because the polyp was removed with a cold tool that did not use heat, the damage was not caused by a burn from the instrument. The exact reason the blood flow stopped remains a mystery, but the doctors suspect it may have been a combination of factors related to the procedure itself. The tablets she took to clean her bowels beforehand might have caused a temporary drop in fluid levels, and the air pumped into the colon to keep it open for viewing could have put pressure on the blood vessels. The patient was admitted to the hospital and treated with a simple, supportive plan. She was given intravenous antibiotics to prevent infection and told to rest her bowel by not eating anything for a few days.

Her recovery was swift. Within two days, her pain had lessened significantly, and the bleeding had slowed. By the fourth day, she was pain-free and had no further blood in her stool. She was allowed to start drinking liquids, which she tolerated well, and by the fifth day, she was eating solid food without any issues. She was discharged from the hospital and felt completely normal. A follow-up exam one month later showed that the damaged area of her colon had healed entirely, returning to a healthy state. This case serves as a reminder that when a patient feels pain and sees blood after a colonoscopy, doctors must look beyond the spot where a polyp was removed. Even in a young, healthy person with no risk factors, a clean resection site paired with new, damaged tissue elsewhere in the colon suggests that blood flow may have been interrupted, requiring a different approach to care.