If you've been experiencing symptoms, such as gastric distress, weight loss, fatigue and anaemia, that your gastroenterologist suspects are being caused by Crohn's disease, then they will arrange for you to undergo a few tests and diagnostic procedures to confirm whether you do have this illness.
The specific tests your doctor will want you to undergo will depend on your presentation and medical history, but Crohn's disease is typically diagnosed using a combination of blood tests and imaging procedures. Blood tests can confirm if you have raised inflammatory markers, which can indicate your body's immune system is attacking your digestive tract. It's common for patients with Crohn's disease to experience intestinal bleeding, and a full blood count can be used to determine if you're anaemic. Once your doctor has the results of your blood tests, they will arrange for you to undergo one or more of the following diagnostic procedures:
Endoscopy is a broad term used when an endoscope, which is a thin, flexible tube with a small camera located at the end, is used to view any part of your digestive tract. Surgical tools can also be inserted through the endoscope to take tissue biopsies, which can be analysed for bacteria or abnormal cell growth. There are several types of endoscopy, and your gastroenterologist will explain the type that's suitable for you.
A colonoscopy involves inserting the endoscope through your anus and allows your doctor to view your entire colon. An upper gastrointestinal endoscopy allows your doctor to view your oesophagus and stomach, and the endoscope is inserted through your mouth. If your doctor wants to view your small intestine, a balloon endoscopy may be recommended. This procedure uses an endoscope with another tube over it that contains a balloon. The doctor can inflate and deflate the balloon as they move the endoscope though your digestive tract. This creates a push-and-pull effect that shortens the intestine by bunching it up over the outer tube, which allows the endoscope to travel further along the digestive tract. Endoscopies are typically not painful, but you can request a sedative if you feel anxious about the procedure.
A CT enterography is carried out in the same way a standard CT scan is, but an intravenous contrast material is used to highlight your intestinal tissue and produce better quality images. This diagnostic procedure is particularly beneficial for understanding what's going on in the small intestine, as this area of your digestive tract can't always be reached with an endoscope if you have a blockage or strictures, which are narrowed areas of bowel that are caused by scar tissue.
The combination of radio waves and a magnetic field allow detailed images of your digestive tract and the organs around it to be captured. This makes MRI an especially useful diagnostic procedure for those who may have a fistula that's attached to surrounding bowel, reproductive organs or the bladder. A fistula is a relatively common complication of Crohn's disease and occurs when an abnormal passageway is formed between the bowel and a surrounding organ.
When your doctor recommends a diagnostic procedure, ensure you understand why they have made their recommendation and what they hope to achieve. They should be happy to answer your questions and explain the risks and benefits of each procedure.