Crohn's disease: symptoms and diagnosis

Crohn's disease is a chronic, inflammatory bowel disease (IBD) that can affect any part of the digestive tract, from the mouth to the rectum. The disease has a fluctuating course, with periods of asymptomatic remission alternating with active inflammatory relapses. Accurate diagnosis is key to appropriate treatment and improved quality of life. In this article, we describe in detail the most common symptoms of Crohn's disease and the tests needed to make a diagnosis to help you understand this complex condition.

From Endomedix Gastroenterology Centre are committed to supporting people with Crohn's disease with state-of-the-art diagnostics and personalised therapy. We know that uncertainty and painful symptoms can make everyday life difficult, so our aim is to provide a clear picture of the disease and treatment options.

What are the symptoms of Crohn's disease?

The symptoms of Crohn's disease can vary widely, depending on which part of the digestive tract is affected and to what extent. They are often non-specific, making early diagnosis difficult.

General digestive symptoms

The most common complaints are:

• Recurrent abdominal pain: Often spasmodic in nature, it typically occurs in the right lower abdomen, but can occur in any area of the abdomen. The pain may worsen after meals.
• Diarrhoea: Persistent, usually non-bloody diarrhoea due to inflammation and malabsorption. If the disease affects the colon, the stools may be mucous.
• Weight loss and loss of appetite: Due to inflammation, pain and insufficient absorption of nutrients (malabsorption), patients often lose weight.
• Tactile abdominal terime: In more advanced cases, a lump in the abdomen can be felt due to the adhesion of the inflamed intestinal pouches.
• Nausea, vomiting: It is particularly common when the upper part of the stomach or small intestine is affected, or when stenosis develops.

Specific and extra-digestive symptoms

Crohn's disease is not limited to the intestinal tract; it can affect many other organs.

• Perianal lesions: The area around the rectum (perianal region) is affected in up to 20-50% of patients and is often the first sign. This includes hard-to-heal rectal fissures (fissures), abnormal ducts (fistulas) and abscesses.
• Fistulas and abscesses: Fistulas are abnormal adhesions that form due to inflammation that spreads through the entire thickness of the intestinal wall. They can join two intestinal pouches (entero-enteric), the intestine and the bladder (entero-vesical), or the intestine and the skin (entero-cutaneous). They can lead to severe infections and abscess formation.
• Oral cavity aphtae: Painful, tiny ulcers on the mucous membranes of the mouth are a common accompanying symptom.
• Joint pain: Inflammation of the joints (arthritis) is common, mainly affecting the larger joints (knees, ankles, wrists).
• Skin and eye symptoms: There may be painful, red nodules on the shin (erythema nodosum) or deep ulcers (pyoderma gangrenosum). Inflammation of the eyes (uveitis, episcleritis) may also be associated with the disease.
• General symptoms: Chronic inflammation can also cause fever, fever, fatigue and anaemia.

How is Crohn's disease diagnosed?

As the symptoms can be indicative of many other conditions (such as irritable bowel syndrome (IBS), infectious enteritis or even appendicitis), a combination of tests is needed to make an accurate diagnosis. The Endomedix Gastroenterology Centre your doctor will follow these steps during the investigation.

1. History taking and physical examination

The doctor will ask the patient in detail about the symptoms, their onset, their nature and any family history of illness. The physical examination includes palpating the abdomen, examining the rectal area and assessing general health.

2. Laboratory tests

Blood and stool tests provide important information about what is happening in the body.

• Blood count: It can show anaemia and a high white blood cell count indicating inflammation.
• Inflammatory markers: Rising levels of C-reactive protein (CRP) indicate active inflammation in the body.
• Stool calprotectin: This marker is a highly sensitive indicator of inflammation of the gut. It can be used to distinguish inflammatory bowel disease from IBS and to monitor the effectiveness of therapy.
• Stool analysis: It is important to rule out infectious causes (e.g. Clostridium difficile, Salmonella).

3. Endoscopic examinations

Endoscopy is essential for the diagnosis of Crohn's disease, as it allows direct visualisation of the intestinal mucosa and histological sampling (biopsy).

• Ileocolonoscopy (colonoscopy of the large and small intestine): The most important diagnostic procedure. During the test, the doctor uses a thin, flexible instrument (endoscope) to look through the entire colon and the last part of the small intestine (terminal ileum), which is the most common site of Crohn's disease. Typical findings are intermittent inflammation (skip lesion), longitudinal ulceration, strictures and a mucosal pattern resembling street stones. Histological samples are taken from several sites, both healthy and abnormal.
• Gastroscopy (gastroscopy of the stomach): In case of upper gastrointestinal symptoms (nausea, stomach pain), it is recommended to examine the oesophagus, stomach and duodenum.
• Capsule endoscopy: If conventional scans do not give a clear result but suspicion of small bowel involvement persists, a swallowable capsule containing a small camera can help to map the entire length of the small bowel.

4. Imaging studies

Imaging can provide information about the condition of the intestinal wall, the extent of inflammation and possible complications (strictures, fistulas, abscesses).

• Abdominal ultrasound: Targeted ultrasound (IUS) shows thickening of the intestinal wall and signs of inflammation.
• CT- and MR-enterography: These special contrast-enhanced scans give a detailed picture of the small intestine and are key to assessing the extent of the disease and identifying complications.
• Pelvic MR: The most accurate imaging method for perianal fistulas and abscesses.

5. Histopathological examination

Microscopic analysis of biopsy samples taken during endoscopy can confirm the diagnosis. Crohn's disease is indicated by nodular inflammation involving deeper layers of the intestinal wall and the presence of special cellular clumps called granulomas (although these are only found in about half of cases).

The next step

The diagnosis of Crohn's disease is a complex process based on a careful evaluation of symptoms, laboratory results, endoscopic and imaging tests. Early and accurate diagnosis is essential to prevent serious complications and maintain a good quality of life through appropriate treatment.

If you are experiencing any of the symptoms described above, do not delay seeking medical advice. Visit Endomedix Gastroenterology Centre experienced specialists and modern diagnostic facilities ensure that you receive the highest quality of care. Contact us with confidence so that together we can find a solution to your complaints.