Hello, XXXXXXX
You mention endoscopy , but I don't know if it included
both upper endoscopy and also colonoscopy.
Occult blood or hidden blood is not visible to the eye
but can be detected by chemical tests .
Our gastrintestinal tract is very long and complex.
The bleeding source could be anywhere from the oral
cavity down to the anus. Most of the time it is possible
to detect the site of bleeding. If the bleeding is active
at the time of examination, it is easier to detect. But if
is slow and intermittent , it is hard to find the source.
In a younger person, such as yourself, the small intestine
may be the site. The duodenum and the rest of the small
bowel can have small ulcers that may be missed on examination
if the examiner does not pay very careful attention to all the
walls of the intestine. Sometimes these ulcers could be hidden
behind folds and overlooked. There are also some vascular
abnormalities involving small blood vessels ,called "Angiodysplasia"
and they can cause hidden bleeding. Crohn's disease in the very
stages can start like very small ulcers and they could be in the
further down in the small bowel.
If you have had an upper GI and small bowel x-ray series. and also
a thorough colonoscopy including the junction of the small and large
intestine (Terminal Ileum) and if they were normal, you may be
a candidate for "Capsule Endoscopy" , a procedure in which you
swallow a small capsule that will travel through the intestine and
take hundreds of pictures of the lining with great details. This
capsule is recovered after you pass it in the stool and then the data
is analyzed from the transmitter using computer. This is the best
way to diagnose what may be the cause of "Occult Blood " in the stool.
I want you to enquire your gastroenterologist to see if the procedure
is being done in your area. Sometimes, university or teaching
hospitals will have this available.
Make sure that you also get a complete blood work including
Celiac panel and IBD-panel.
I wish you well.

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