Functional dyspepsia (FD; irritable stomach syndrome; dyspeptic complaints) is a diagnosis of exclusion. Only after all organic causes have been excluded with certainty may the diagnosis be made.
Mandatory medical device diagnostics.
- Esophago-gastro-duodenoscopy (EGD; endoscopy of esophagus, stomach, and duodenum) with biopsies (sampling) from all suspicious lesions + H. pylori testing (biopsy from duodenum); in Barrett’s esophagus, additional 4-quadrant biopsies.
- Abdominal ultrasonography (ultrasound examination of the abdominal organs) – for basic diagnostics to exclude cholecystitis (gallbladder inflammation), cholecystolithiasis (gallstone disease) and pancreatitis (pancreatitis).
- Colonoscopy (colonoscopy) – for irritable bowel disease.
Optional medical device diagnostics – depending on the results of the history, physical examination, laboratory diagnostics and obligatory medical device diagnostics – for differential diagnostic clarification depending on the predominant symptoms.
- Fructose H2 breath test – to exclude fructose intolerance.
- Lactose H2 breath test – to exclude lactose intolerance.
- Endosonography (endoscopic ultrasound (EUS); ultrasound examination performed from the inside, i.e., the ultrasound probe is brought into direct contact with the internal surface (for example, the mucosa of the stomach/intestine) by means of an endoscope (optical instrument)). – When pancreatic cancer (cancer of the pancreas), gastric cancer (cancer of the stomach) is suspected.
- Colonoscopy (colonoscopy)
- Computed tomography of the thorax/chest (thoracic CT) if malignant (malignant) disease is suspected.
- Reflux diagnostics (24-h pH-metry or 24-h impedance measurement); see below gastroesophageal reflux disease/medical device diagnostics.
