i am so astonished to read what you have written, before my appendix was removed, i never had diarrhea problems. after my appendix was removed i had a number of side effects in the 2 weeks that followed such as bronchitis, breaking out into spots and blackouts. in the months which followed i would get diarrhea from eating food at weddings, conferences etc. 4 months later i went to southern asia, where it became continuous and has been so ever since. i think i might have picked up rotavirus or something, which could have also led to a gastrointestinal disease, but no tests, colonoscopies or anything tells of any problems.
according to wikipeadia, "the appendix serves as a safe haven for useful bacteria when illness flushes those bacteria from the rest of the intestines" and "diarrhea is one of the leading causes of death in developing countries, indicating that a role of the appendix as an aid in recovering beneficial bacteria following diarrhea may be extremely important in the absence of modern health and sanitation practices".
I would be really interested to learn the link.