Why does your doctor order so many tests?

Your doctor orders the tests needed to assess your intestinal health.   These include blood tests, stool tests, endoscopy, imaging tests.

If you do not have a diagnosis, but have many symptoms, these tests can help to diagnose or confirm no diagnosis of inflammatory bowel disease.

If you have a diagnosis of IBD, even if you do not have symptoms, your disease may be active.  Therefore, your doctor may order blood and stool tests, endoscopy, and imaging, on a regular basis to determine if your intestines are healthy or if there is active disease.  This is important, as your medications may need to be adjusted if you have active disease, even if you feel well!   It is important to get your disease in remission because of potential long term effects (e.g. colon cancer risk is higher if you have chronic active colitis, or you can develop strictures of the bowels if there is ongoing inflammation)



Common blood tests assess your overall health and nutrition.   These include

  1. Complete Blood Count (CBC) – your red bloods cells (hemoglobin), white blood cells, platelets
  2. Iron studies (ferritin, iron, TIBC) – to see if you have enough iron
  3. Vitamins – such as Vitamin B12, Vitamin D – if these are too low – you may need to take supplements.
  4. electrolytes (Na, K, PO4, Mg, Ca) – if you have lots of diarrhea or are not taking enough by mouth, you could be low in these.   Being low in these may lead to heart problems, muscle problems, nerve problems.  you may need to take supplements.
  5. C-reactive protein (CRP) – marker of inflammation in the blood

More specific blood tests include drug levels and drug metabolite (break down product) levels.  These include

  1. thiopurine (Imuran, 6-MP) metabolite levels
  2. biologic (infliximab (Remicade, Inflectra), adalimumab (Humira), golimumab (Simponi), ustekinumab (Stelara), vedolizumab (Entyvio) drug levels and anti-drug antibody levels



Stool tests are ordered for TWO main reasons.

  • rule out infections

    1. people with IBD are at higher risk for intestinal infections
    2. these include
      1. clostridium difficile (C diff) – a bacteria that causes significant problems with the colon and lots of diarrhea
      2. stool cultures – to rule out common food borne and environmental borne infections
      3. ova and parasites – to rule out worms and parasites
  • assess intestinal inflammation

    1. a non invasive method to assess for intestinal inflammation
    2. fecal calprotectin (FCP) is a protein found in neutrophils (white blood cells) and thus fecal calprotectin is the concentration of this protein in the stool.  Therefore FCP gives an idea of how much inflammation (white blood cells) are in the intestines.
      1. see the CDHF FCP video



Endoscopy tests are procedures where your gastroenterologist will use a scope (long thin tube that has a camera at the end) to look into your gut!


  • how is gastroscopy done?
    • a small tube with a camera at the end (the gasroscope) will be inserted through your mouth into your esophagus (your swallowing tube) down into your stomach
    • we will look into your mouth, esophagus (swallowing tube), stomach, and first part of your small bowel
    • My Health Alberta info on gastroscopy
  • what preparation is there?
    • the only preparation is NOTHING TO EAT after midnight





  • how is sigmoidoscopy done?
    • this is a short version of the colonoscopy where we look into your rectum and sigmoid only
  • what preparation is there?



  • how is pouchoscopy done?
    • if you had pouch surgery, we often look into the pouch with a short scope to ensure it is healthy
  • what preparation is there?
    • sometimes you may have to do an enema to clear the bottom end



  • how is ileoscopy done?
    • if you have an ileostomy or colostomy, we will look through the opening (stoma) with a small scope into your remaining bowel
  • how is ileoscopy done?
    • sometimes you may have to do some preparation to clear out the small intestine or remaining large intestine



Common imaging tests to assess your intestinal and gut health include

  1. X-rays – plain flat plate x-rays of your abdomen can show the gas/stool pattern!
  2. CT (computed tomography)
    1. CT enterography looks at the small bowel.  The radiologist will have you drink some sweet fluids quickly just before doing the imaging, then you lie on the table, are passed into the CT RING, and in a few minutes the CT will be done.  You may receive some IV dye contrast. This is an important test to look for inflammation of the bowels, stricturing or scarring.
    2. CT abdomen/pelvis without the special enterography protocol is also used, more for ruling out abscesses and obstructions, or to look at the solid organs in the abdomen and pelvis.
  3. MR (magnetic resonance) – MR imaging (MRI) are used more frequently to avoid radiation.
    1. MR enterography looks at the small bowel.  The radiologist will have you drink some sweet fluids quickly just before doing the imaging, then you lie on the table, are passed into a long tube (noisy) and in about 30 to 45 minutes, the machine will take many images, you may receive some IV dye contrast, and then the test will be done.
    2. MR pelvis is good for looking at fistulas, and specifically the perianal (around the bum) fistulas and abscesses.
  4. U/S (ultrasound) – ultrasound uses sound waves to look at the inside organs.   Radiologists use special techniques to look at the bowel wall and structures for any inflammation, fluid collections, stricturing.

IF you are pregnant or might be pregnant, you need to inform your physician and the radiologist and technician.  Some of the above tests are avoided during pregnancy or modified to reduce risk to the fetus.