Diagnosis

To detect an ulcer, your doctor may first take a medical history and perform a physical exam. You then may need to undergo diagnostic tests, such as:

• Laboratory tests for H. pylori. Your doctor may recommend tests to determine whether the bacterium H. pylori is present in your body. He or she may look for H. pylori using a blood, stool or breath test. The breath test is the most accurate.

  For the breath test, you drink or eat something that contains radioactive carbon. H. pylori breaks down the substance in your stomach. Later, you blow into a bag, which is then sealed. If you're infected with H. pylori, your breath sample will contain the radioactive carbon in the form of carbon dioxide.

  If you are taking an antacid prior to the testing for H. pylori, make sure to let your doctor know. Depending on which test is used, you may need to discontinue the medication for a period of time because antacids can lead to false-negative results.

• Endoscopy. Your doctor may use a scope to examine your upper digestive system (endoscopy). During endoscopy, your doctor passes a hollow tube equipped with a lens (endoscope) down your throat and into your esophagus, stomach and small intestine. Using the endoscope, your doctor looks for ulcers.

  If your doctor detects an ulcer, a small tissue sample (biopsy) may be removed for examination in a lab. A biopsy can also identify whether H. pylori is in your stomach lining.

  Your doctor is more likely to recommend endoscopy if you are older, have signs of bleeding, or have experienced recent weight loss or difficulty eating and swallowing. If the endoscopy shows an ulcer in your stomach, a follow-up endoscopy should be performed after treatment to show that it has healed, even if your symptoms improve.

• Upper gastrointestinal series. Sometimes called a barium swallow, this series of X-rays of your upper digestive system creates images of your esophagus, stomach and small intestine. During the X-ray, you swallow a white liquid (containing barium) that coats your digestive tract and makes an ulcer more visible.