Peptic Ulcers - Diagnosis

(Page 2)

Dyspepsia may also occur with gastritis, stomach cancer, or as a side effect of certain drugs, including NSAIDs, antibiotics, iron, corticosteroids, theophylline, and calcium blockers used to treat high blood pressure.

Noninvasive Tests for Gastrointestinal (GI) Bleeding.

When ulcers are suspected, the doctor administers tests to detect any bleeding. They include a rectal exam, a complete blood count, and a fecal occult blood test (FOBT). The FOBT tests for hidden (called occult) blood in stools. Typically, the patient is asked to supply up to six stool specimens in a specially prepared package. A small quantity of feces is smeared on specially treated paper, which reacts to hydrogen peroxide. If blood is present, the paper turns blue.

Noninvasive Screening Tests for H. Pylori

Simple blood, breath, and stool tests can now detect H. pylori with a fairly high degree of accuracy. It is not entirely clear, however, which individuals should be screened for H. pylori.

Candidates for Screening. Some doctors currently test for H. pylori only in individuals with dyspepsia who also have high-risk conditions, such as the following:

• Strong indications for ulcers, such as weight loss, anemia, or indications of bleeding.
• History of active ulcers.
• Risk factors for stomach cancer or other complications from ulcers.

Smokers and those who experience regular and persistent pain on an empty stomach may also be good candidates for screening tests. Some doctors argue that testing for H. pylori may be beneficial for patients with dyspepsia who are regular NSAID users. In fact, given the possible risk for stomach cancer in H. pylori infected people with dyspepsia, some experts now recommend that any patient with dyspepsia that lasts longer than 4 weeks should be given blood tests for H. pylori. This is a subject of considerable debate, however.

Specific Screening Tests for H. Pylori. The following are the screening tests used or under investigation for H. pylori.

• Breath Test. A simple test called the carbon isotope-urea breath test (UBT) can identify up to 99% of people who harbor H. pylori. Up to 2 weeks before the test the patient must be off any antibiotics, bismuth-containing agents (such as Pepto-Bismol), and proton-pump inhibitors (PPIs). As part of the test, the patient swallows a special substance containing urea (a compound in mammals metabolized from nitrogen) that has been treated with carbon atoms. If present, the H. pyloribacteria convert the urea into carbon dioxide, which is detected and recorded in the patient's exhaled breath after 10 minutes.
• Blood Tests. Blood tests are used to measure antibodies to H. pylori, with results available in minutes. Diagnostic accuracy is reported at 80% and 90%. One such important test is called enzyme-linked immunosorbent assay (ELISA). An ELISA test of the urine is also showing promise in children.
• Stool Test. A test to detect genetic fingerprints of H. pylori in the feces appears to be as accurate as the breath test for initial detection of the bacteria and for detecting recurrences after antibiotic therapy.