What is one method used to diagnose H. pylori?

A biopsy is a method used to diagnose H. pylori because it allows for direct examination of gastric tissue, which can reveal the presence of the bacteria. During an endoscopy, a small tissue sample from the stomach lining is taken and then analyzed for H. pylori either through histological examination or specific tests for the bacterium.

While culturing the bacteria is indeed a diagnostic method, it typically requires a biopsy sample for the culture to be performed, and a biopsy is more direct in assessing the state of the gastric mucosa. Ultrasound and CT scans are imaging techniques that can provide information about gastric abnormalities but do not specifically diagnose H. pylori infection.