Brief Answer:
Further steps to deciding the diagnoses and treatment according to it

Detailed Answer:
Hello,

Thank you for using HCM to post your health query.
I read carefully your question and I understand your concern.

A chronic diarrhea it is a complicated diagnoses and many tests should be done to rule out the cause of it.
It is good that you have ruled out many causes by doing the colonoscopy.
Also, one possible diagnoses it is parasites in the stool. So doing a stool for ova and parasite will help a lot.
Sometimes drugs can give diarrhea. Have you seen any relation to any of them in particular? Also, some foods may give diarrhea, but in your case you would need to eat that food a lot, like every day and commonly.

If there has been blood or mucus in the stool at any time, then maybe the colonoscopy its not enough. Many problems, do not show a result in the colonoscopy, because it may be just the beginning of them and the lesions hasn't started yet. To decide the final diagnoses, a biopsy of the bowel would have been needed.

These are my thoughts. Hope this is helpful and that they will lead you a bit to the next steps of follow-up with your local physician.
Let me know if you need more clarifications.
Otherwise please close and rate the answer.

Regards,
Dr. Papaqako

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