How to diagnose a duodenal ulcer

The main diagnostic methods for duodenal ulcers include: 1. **Gastroscopy**: As the gold standard for diagnosis, this procedure allows direct visualization of ulcers in the duodenal mucosa, enabling accurate assessment of the ulcer's specific morphology, size, and location. Biopsies can also be taken from the ulcer margin for histopathological examination. 2. **Breath Test**: Such as the 13C or 14C-urea breath test, which is used to detect *Helicobacter pylori* (Hp) infection. A positive result indicates Hp infection and provides guidance for treatment. 3. **Upper Gastrointestinal Barium Meal Study**: This may be selected for patients with poor cardiopulmonary function who cannot tolerate gastroscopy. It allows indirect assessment of the presence of a duodenal ulcer by observing the flow of barium through the gastrointestinal tract. 4. **Other Tests**: For example, fecal occult blood testing can detect the presence of active bleeding. Gastric acid analysis and gastric motility studies may help diagnose other gastric or duodenal disorders. When necessary, additional tests such as CT scans, gastrin level measurements, and tumor marker testing may also be performed.