Diagnosis of Crohn’s disease using stool samples

Stool samples can be used to quickly and easily determine blood loss via the intestine. The hemoccult test (guaiac test) is particularly suitable. With this test, even the smallest amounts of blood in the stool can be determined.

This occult (hidden) blood, invisible to the eye, can be detected by a simple test. However, blood in the stool is not a specific indication of Crohn’s disease. It merely substantiates an existing suspicion.

Bacteria such as Campylobacter, Yersinia, Salmonella or Shigella can also be detected in stool samples. Adeno-, Noro-, or Rotavirus can also be detected. These can, for example, cause inflammation of the intestines and complaints that are similar to Crohn’s disease.

Detection of corresponding intestinal pathogens is more likely to rule out the diagnosis of Crohn’s disease. It is often useful to determine calprotectin or lactoferrin in the stool. These two markers are inflammation parameters and are correspondingly often elevated in Crohn’s disease.

Calprotectin is a substance from neutrophil granulocytes, which is released during inflammation in the intestine. The advantage is a particularly high sensitivity in the case of Crohn’s disease. Lactoferrin is a substance that occurs, for example, in digestive secretions.An elevation in the stool also indicates an inflammation of the intestines.

Diagnosis of Crohn’s disease by x-ray

In this diagnostic procedure, a probe is inserted through the nose and throat into the small intestine. Water-soluble contrast medium is administered via the probe. X-rays are then taken at various points in time to show the course of the contrast medium through the intestine as completely as possible.

The intestinal changes typical of Crohn’s disease can thus be easily and gently displayed for the patient. These include primarily passenger disorders and constrictions (stenoses) in isolated bowel segments. Also typical are so-called fistulas.

These are connecting passages between individual sections of the intestine. X-rays play another role in children with Crohn’s disease. The disturbance of nutrient absorption often leads to delayed growth in children. The bone age can be determined by means of an x-ray of the hand and can support the diagnosis of Crohn’s disease.