Dr. Schär Institute

The diagnostic approach should begin with a detailed medical history to correlate the symptoms of the patient with those typical of IBS. The patient should also be asked for a subjective assessment of the severity and impact of symptoms on daily life in order to gain an understanding of the disease burden for the patient. Exclusion of other potential causes in order to avoid mis-diagnosis.
 

Diagnosis according to definition

The Rome III criteria [1,2] are the gold standard for IBS diagnosis. These are outlined below:

Recurrent abdominal pain or discomfort at least 3 days/month in the last 3 months associated with two or more of the following:

1. Improvement with defecation
2. Onset associated with a change in frequency of stool
3. Onset associated with a change in form (appearance) of stool

Despite the availability of Rome III diagnostic criteria, it may still be challenging for healthcare professionals to differentiate IBS from organic disease such as bowel cancer or inflammatory bowel disease, bile acid diarrhea, celiac disease/NCGS or gastrointestinal food allergy. For example, research suggests that undetected celiac disease is present in more than 4% of patients with typical IBS [3]. A detailed case history should be taken and if suspicion arises or red flags are noted then patients should be referred for the appropriate tests or investigations.