Hi,
Thanks for posting your query at DoctorSpring.com. I am Dr.R.K and I am pleased to assist you.
Abdominal pain immediately after taking food followed by rushing to bathroom for a bowel movement point towards irritable bowel syndrome. This is possible if the symptoms have been for more than 6 months. But if it is only for the past few days, then irritable bowel syndrome is unlikely.
Infection and malabsorption should also be ruled out. There is no specific diagnostic test for irritable bowel syndrome. It is a functional disease and organic diseases should be ruled out first. Presuming it to be chronic, a complete blood count, blood glucose test, stool analysis, thyroid function test, test for celiac and a colonoscopy test should all be done.
I hope that answers your question. Please let me know if I can assist you further.
Regards,
Dr. R.K