Brief Answer:
Colonoscopy with biopsy can rule out celiac disease.

Detailed Answer:

Hello,

As per your queries answer is after seeing all your symptoms as well as duration of illness your problem is very suggestive of Irritable bowel syndrome. However IBS is a diagnosis of exclusion as there is no test to confirm you have IBS, It means that when you have nothing or all your investigations are normal you are labelled as having IBS.
what exactly is IBS
Its a disorder affecting large intestine.
The exact cause of irritable bowel syndrome is not yet known but studies suggest that a lot of factors may play a major role. Even clinical presentation of patients is also different. Some patients presents with loose stools some with constipation while other may just have pain and bloating. Every patient with IBS is different with varying symptoms.. So frankly speaking (IBS) represents a functional disorder of gastrointestinal tract without the presence of an anatomic defect SO in lay mans language till date we are not sure what's the exact cause of this problem as intestines are anatomicaly normal but physiologically they are having problems. So the million dollar question is how to repair a system when you don't know which part of it is faulty(Some says it can be brain other says it can be hormone anxiety age etc etc).Now symptoms of IBS overlaps the symptoms of Celiac disease(Inflammatory bowel disease) Hence without proper colonoscopy with biopsy of intestine no doctor can give you a professional diagnosis. Hence Initially i would suggest you to go for colonoscopy and stool microscopy test. If both these tests are normal i would like to start you on protocol of IBS treatment.
Serum calprotectin is not a very reliable test and is used just for screening.
Go for a colonoscopy guided biopsy of intestine to rule out celiac disease.
Thanks!

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Brief Answer:
Colonoscopy has to be done.

Detailed Answer:
Hello again,
As such colonoscopy is a safe and invasive test.Mild bleeding or pain etc can be there but its non fatal.A tube containing a camera would be inserted into your ano rectal canal and from that a small sample of tissue would be taken.This is a highly sensitive test and accuracy rate is about 99%.

No tests through blood are screening once and are not of much use.

Celiac disease is a non fatal disease and symtoms can be controlled very well by medications and life style changes.
Compared to IBS treating celiac is much easier and more effective treatments are there .
Thanks!

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