Brief Answer:
IBS and other causes as explained.

Detailed Answer:
Hi.
Thanks for your query.
I have read the history related to appendectomy, sharp pains persisting in right lower abdomen, normal investigations, course of medicines for cecum infection (typhlitis), wants opinion.

Please tell me few details:
- When was the appendectomy performed ?
- Was Appendicitis a clinical diagnosis or seen on USG and / CT scan ?
- Any other associated symptoms like
nausea,
vomiting,
distension,
loose motions
or constipation,
distension of abdomen,
burning urination,
back pain
or any thing related or unrelated (that you may think) ?
- Any problem related to the testis / scrotum

Since all the reports you mentioned are normal, the possible causes can be:
- Typhlitis (infection of the cecum)for which you have completed the course.
- IBS - Irritable Bowel Syndrome as all the relevant reports said to be normal.
- Urinary tract infection.
- Spinal problem at the thoracic 10 level causing referred pain in the appendix region.
- Vascular

I would advise you the following:
-Repeat blood, urine and stool ( stool for three days) tests.
-MRI of the Thoracic spine and muscles related to the spine and ask to include the area of pain.
- A good Clinical evaluation, actual Physical examination and correlation with the symptoms, investigations, and effect of the medicines in future.
- Till then continue the probiotics; Trial treatment on the basis of IBS can be started under the guidance of your Doctor. You should discuss this in detail with your treating Doctors.

I hope this answer helps you to get a proper diagnosis, and get a proper further treatment. Please feel free to ask for more or if you need further clarifications if you feel there is a gap of communication.

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