A surprising cause of rectal bleeding

“I can’t stand the site of blood!”

We’ve all heard that adage. Blood can provoke emotional reactions from even steely muscle-bound bodybuilders. We gastroenterologists routinely receive fearful phone calls from patients who have observed even minor rectal bleeding. Fortunately, in most of these cases, there is a benign explanation for the sanguinary seepage.

If blood repels you, then gastroenterology should not be on your short, or even long list of professions under consideration. We confront blood every day. Of course, blood is the elixir of life as it courses into every remote recess of our bodies. But, when blood loses its bearings, takes a wrong turn, and emerges errantly from our gastrointestinal tract, then gastroenterologists — or G-men — are called in. Indeed, searching out the site of blood leakage in patients is one of our primary diagnostic tasks. You might say that blood is our “bread and butter.”

I recently evaluated a patient in my office that confounded me and my staff. Collectively, we have seen thousands of cases of internal bleeding, and yet we had never seen such a case as this before. Will our discovery be a game changer in my specialty? Should I publish this case in a medical journal to alert other practitioners of our groundbreaking discovery? Should I start out on the lecture circuit?

Here are the facts.

A young woman underwent a colonoscopy in my office to evaluate abdominal pain and other digestive complaints. There was no rectal bleeding. Yet, during the colonoscopy, there was blood throughout her colon, an entirely unexpected finding. Now, we physicians are trained to deal with unexpected eventualities, but we are as surprised as anyone when we confront an unanticipated situation. We like stuff to make sense. Suddenly, I needed to add diagnostic considerations to explain this surprising finding. I assiduously searched with my scope for the origin of the bleeding, but I could not identify any lesion.

At that moment, I realized what must have occurred. This patient, against our instructions, must have mixed the laxative with a red beverage, which was now masquerading as blood. I smugly shared this hypothesis with my staff and dispatched a nurse out to the waiting room to ask the mother about pertinent laxative details. The nurse returned informing us that the patient mixed the laxative with a blue beverage. My smugness evaporated. What is happening here?

After the patient was recovering and awake, we inquired about any ingestions that she did not previously disclose. At that moment, she offered a full confession. At midnight, she reached for a snack that we will now add to the list of forbidden foods prior to undergoing a colonoscopy. Mystery solved.