the case of the bloody poo

Mike and I were trading stories about medical cases that we've seen recently. My fault, really, since I'm obsessed with medicine and can't stop talking about work (since that's all I do anymore, anyway). After I told Mike about my current patient with weight loss of unknown origin and a recent case of Q fever endocarditis, Mike told me the following pediatrics case that he saw today:

"Six-year-old boy, the story is that he took a dump this morning and it was bright red. No stomach pain, might have had a similar poop last night, no vomiting, heart rate is stable, no signs of dehydration or shock, kid is in no apparent distress."

"INTUSSUCEPTION!" I yell.

"No. So the resident does a digital rectal exam, and his glove comes out bright red and covered in poo. The resident smears his glove on a FOBT (a strip of paper that turns color when poo with blood gets smeared on it, even if the blood is not visible to the naked eye), and the strip never changes color."

"The strip should change color," I said, "so either the strip is defective or it's not really blood."

"Right, but what is it?"

"Meckel's?" I said.

"No. Then we asked the boy to pee in a cup. Why?"

"To check for hematuria or proteinuria?"

"No, even simpler."

"To see if his pee is red too?"

"Yes! Because eating too many beets can color your poop and your pee."

"Was it red?" I asked.

"No, his urine was not red."

"GI bleed?" I said, "he doesn't seem to be in distress. He's too young for colon cancer, diverticulitis, or ulcers.

"No. Give up?" Mike asked.

Yes.

"So the resident is totally clueless. We talk to the attending, and the attending laughs. He says that a couple years ago, when RED HOT CHEETOS hit the market, there was a huge outbreak of kids with bright red poo. And this was the case."