Apparently I can't rule out any parasite based on recent tests. I had hoped investing in a visit to the infectious diseases specialist would provide a definite answer and dependable solution but I'm beginning to understand that parasite identification and treatment is a challenge even to experts. He laughed when I told him that I was basically very healthy but I needed a pill that would cure this one simple problem that has been devastating my life for the past 20 years. Now I know what was so funny! Thanks for the info. I'll keep trying.