Irritable bowel syndrome (IBS) manifests as a heterogeneous clinical picture in terms of the type and severity of symptoms, affecting around 16% of the population. Diagnostically, IBS is a challenge for the physician, and drug therapy is often unsatisfactory for the patient – also due to false expectations.
According to the updated S3 guideline from 2021, three aspects should be given to establish the diagnosis of irritable bowel syndrome:
- There are chronic (i.e., lasting longer than three months) or recurrent complaints that are referred to the bowel by the patient and physician and are usually accompanied by bowel movements.
- The complaints should justify that the patient seeks help and/or worries about it, and be so severe that the quality of life is relevantly affected by it.
- The prerequisite is that there are no changes characteristic of other clinical pictures that are probably responsible for these symptoms.
Essential in this definition are the factors time (longer than three months), limitation of the complaints to the intestine and the patient’s suffering. “This was done to distinguish IBS from more trivial disorders of well-being, which may manifest themselves similarly but not as persistently,” explained Prof. Dr. Wolfgang Fischbach, specialist in internal medicine, gastroenterology, Joint Practice for Gastroenterology, Aschaffenburg (D), and contributor to the guideline [1].
The clinical picture of IBS is determined by four factors: pain/cramps, constipation, flatulence/flatulence, and diarrhea. Of course, several of these symptoms can occur simultaneously. In addition, patients with IBS may also have symptoms in other parts of the gastrointestinal tract: About 27% of all IBS patients also suffer from functional dyspepsia; conversely, 37% of these sufferers also experience IBS. The higher the number of organs affected by functional complaints, the more severe the symptom severity, and extragastrointestinal symptoms such as depression or anxiety also increase with the number of GI organs affected.
Differential diagnoses |
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– Tumors: CRC, in women especially also ovarian Ca – Chronic inflammatory bowel disease (IBD), microscopic colitis – Celiac disease – Lactose / fructose intolerance – Bacterial Infection (SIBO) – Diverticular disease (esp. SUDD: – symptomatic uncomplicated diverticular disease). |
Rarer: – Intestinal ischemia – intestinal motility disorders (pseudo-obstruction) – Bile acidosis syndrome – Medication-NW – etc. |
No specific biomarkers
Once the suspected diagnosis of IBS has been made, however, there are no specific biomarkers for a positive diagnosis; other diseases may present similarly and must be excluded by means of differential diagnostics (box). Prof. Fischbach pointed out in this regard. mainly ovarian carcinoma: In a case-control study of 112 patients with ovarian Ca (vs. 1060 matched controls), 80-90% developed typical IBS before cancer diagnosis. The most important leading symptoms here were abdominal distension and bloating (OR 250!), abdominal cramps/pain (OR 12), and dyspeptic symptoms (OR 17). Distension and abdominal pain occurred significantly more frequently (>180 days before diagnosis).
When a patient presents to his or her physician with appropriate complaints, a history with physical (including rectal) examination should first take place, followed by a basic laboratory (blood count, CRP, liver enzymes, creatinine, celiac disease AK, fecal calprotectin, fecal pathogens), sonography, and, if necessary, gynecological referral. If organic causes are suspected or alarm signs such as weight loss, blood in the stool or anemia are present, IBS can already be ruled out.
If the predominant symptom is diarrhea, the guideline [2] recommends a comprehensive diagnosis already at the initial presentation. If diarrhea-dominant IBS is not present, probationary therapy or symptom-oriented further diagnostics are advised. According to Prof. Fischbach, this is individually dependent on, among other things, the severity, duration and dynamics of the symptoms or the patient’s age, personality and level of suffering and will usually include an ileocolonoscopy, ÖGD with duodenal biopsies and individual functional tests (lactose, fructose).
The expert advises to carry out the described measures promptly, comprehensively and thoroughly once during the symptom-oriented further diagnostics and to refrain from repeat examinations in the further course. Food intolerances must be taken into account in all of this: In this case, keeping a food symptom diary for 4 weeks with subsequent abstinence and re-exposure, if necessary, is quite reasonable. The guideline does not recommend intestinal ecograms.
Every therapy is initially probationary
At the beginning of the treatment, there should be a comprehensible explanation of the clinical picture. This gains trust and creates a basis for a good doctor-patient relationship, which is needed in the long term with these patients. This includes, above all, the presentation of the treatment concepts and their realistically achievable goals. This is followed by general measures such as identifying and avoiding triggers like certain foods, lack of sleep or alcohol. Exercise and sufficient fluid intake, on the other hand, have a favorable effect.
Only if this is unsuccessful does drug therapy follow. “Here, we are guided by the predominant symptom,” explained Prof. Fischbach (Fig. 1). In principle, it should be emphasized that every therapy is initially probationary. This should also be made clear to patients. Success is measured by symptom improvement, although it makes sense to try other medications successively if success is insufficient.
In individual cases, further accompanying measures may be considered. These include, for example, antidepressants, psychotherapy, autogenic training, yoga or osteopathy. According to the guideline, other therapeutic options include a low-FODMAP diet (“recommended”) and peppermint oil and other phytotherapeutics (“to be considered”). In contrast, there is no recommendation for prebiotics and fecal microbiome transfer.
Take-Home Messages
- IBS is characterized by abdominal pain, bloating, and bowel changes. The symptoms are not specific.
- Careful, individually oriented differential diagnosis is required.
- At the beginning of the therapy there is the communication of an understandable disease picture.
- Therapy includes general measures, drug approaches, and various adjunctive measures.
- IBS is an “organic” disease, not a functional or psychosomatic disorder.
Congress: StreamedUp! GastroLive
Sources:
- Fischbach W.: Vortrag «Reizdarmsyndrom», Streamed
Up! GastroLive «Diarrhö und Blähungen – was steckt dahinter?», 21.03.2023. - Update S3-Leitlinie Reizdarmsyndrom: Definition, Pathophysiologie, Diagnostik und Therapie, Juni 2021, AWMF-Registernummer: 021–016.
GASTROENTEROLOGIE PRAXIS 2023; 1(1): 21–22