Crohn's disease: Everything about symptoms, intestinal examination, and modern treatment

3D anatomical render of small intestine and colon in soft pink tones with patchy red inflamed segments and areas of narrowing, symbolizing Crohn's disease. Medical realism with clinical clarity.

Are you experiencing recurring stomach pain, weight loss, or perhapsbleeding from the rectum? These could be signs of Crohn's disease. Unlike ulcerative colitis, this disease can affect the entire digestive system, making a thoroughintestinal examinationand early diagnosis essential to avoid complications such as fistulas or narrowing.

In this post, we take a closer look at how life with Crohn's disease is managed in Denmark and why acolonoscopyis the most important tool in the toolbox.

What is Crohn's disease?

Crohn's disease is a chronic inflammatory bowel disease (IBD) that can cause inflammation in all layers of the intestinal wall. While colitis only affects the large intestine, Crohn's disease can occur anywhere from the mouth to the rectum—but most often in the transition between the small and large intestines.

Typical symptoms include:

Pain (often in the lower right side of the abdomen).
Diarrhea (sometimes with bleeding from the rectum).
Fatigue and unexplained weight loss.
Fever during periods of flare-ups.

Scientific focus: Crohn's patients have an increased risk of strictures (narrowing) due to transmural inflammation (inflammation through all tissue layers). Early biological intervention is key to changing the natural course of the disease.

Source: Torres et al., Lancet, 2017

The diagnosis: More than just one bowel examination

If Crohn's disease is suspected, acolonoscopywith biopsy is the "gold standard," but since the disease can also hide in the small intestine, Danish hospitals often supplement this with other tests:

Colonoscopy:An examination of the colon and the last part of the small intestine using a telescope.
MRI or CT scan:Often used to evaluate the small intestine and check for abscesses or fistulas.
Capsule endoscopy:A small pill with a camera that you swallow to film the small intestine.

Why are biopsies important?

During a colonoscopy, small tissue samples are taken. In Crohn's disease, the pathologist looks for "granulomas" (small clusters of cells), which are found in approximately 50% of patients and confirm the diagnosis.

Treatment strategy in Denmark

The goal of treatment in Denmark is mucosal healing. An individual step-by-step model is followed:

Step 1: Acute treatment (adrenal cortex hormone)

Prednisolone(tablets) orBudenofalk(locally acting in the intestine) are often used for flare-ups. Budenofalk has fewer side effects, as it primarily acts in the area where the small and large intestines meet.

Step 2: Maintenance (Immunomodulatory)

Thiopurines(Imurel/Azathioprine) are often used to prevent new flare-ups. Unlike ulcerative colitis, 5-ASA (Pentasa) often has a limited effect on Crohn's disease.

Step 3: Biological medicine (frontline treatment)

In Denmark today, biological treatment is quickly initiated for moderate to severe Crohn's disease in order to avoid surgery.

Type	Examples (Denmark)	Especially for Crohn's disease
TNF inhibitors	Infliximab (Remsima),Adalimumab (Humira)	The gold standard, especially effective against fistulas.
IL inhibitors	Ustekinumab (Stelara)	Blocks IL-12/23. Good for those for whom TNF inhibitors do not work.
Integrin inhibitors	Vedolizumab (Entyvio)	Intestinal selective – fewer side effects in the rest of the body.
Small molecules	Upadacitinib (Rinvoq)	New tablet treatment (JAK inhibitor) approved for Crohn's disease.

Scientific focus: Studies show that combination therapy (e.g., infliximab + azathioprine) is more effective in achieving complete healing of the mucosa than monotherapy.

Source: Colombel et al., NEJM (SONIC study)

Living with Crohn's disease and follow-up

Even if you are undergoing treatment, regular check-ups are necessary. In Denmark, we use:

Calprotectin (stool sample):An easy way to measure inflammation without a fullintestinal examination.
Blood tests:To check for iron deficiency and vitamin status (especially B12).

An important tip:Smoking is the biggest risk factor for worsening Crohn's disease. In some cases, quitting smoking can be just as effective as medical treatment.