Weird discovery made in man's stomach leaves doctors completely baffled

A man in Missouri has left doctors baffled after they discovered a live animal inside his colon.

The patient, 63, went in for a regular colon cancer screening, but what doctors found was most definitely irregular.

When doctors put a camera in the man's intestines for his colonoscopy, they were shocked to discover a fully intact fly.

The fly was found alive at the top of the large intestine, and would not move when doctors tried to prod it.

Doctors are mystified as to how it was fully intact and alive but are suggesting it could've ended up inside the man after he ate contaminated lettuce.

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The fly was found in the transverse colon, the upper area of the organ, but did not cause the patient to feel any symptoms at all.

Doctors questioned him when they made the shocking discovery but he was equally as surprised, having no idea how it could've got there.

Before a colonoscopy, you must only consume clear liquids, and he maintains that's exactly what he did.

The evening before he had to start this fast, the man ate a pizza and lettuce, obviously not meaning to also consume a fly while he was at it.

Thought it is very rare, flies has been known to lay eggs on fruit and veg which then hatch inside the intestine after surviving the stomach acid. This can lead to a condition called myiasis.

The doctors have now published this extraordinary case in the American Journal of Gastroenterology. They said: "This case represents a very rare colonoscopic finding. [It is a] mystery on how the intact fly found its way to the transverse colon."

It was not clear whether the fly ended up in the man's intestine due to what food he ate, but previous cases of myiasis has been linked to rotten bananas.