You Examine a Patient Who Is Complaining of Belching (Burping)

Multiple Choice

You examine a patient who is complaining of belching (burping) , bloating, and some vomiting. She also has some abdominal discomfort which she describes as a dull, burning pain that is worse when she is hungry and is often relieved when she takes antacids. You suspect that she may have Helicobacter pylori gastritis, and send her for a urea breath test. The breath test is positive; based on this, you get the patient's stool tested for blood, and you send her for an endoscopy, during which a biopsy is taken. Your diagnosis is confirmed by the results of these tests and that she does indeed have H. pylori.
-Your patient asks you to explain how the urea breath test works. You tell her that in the test, she had been asked to swallow urea containing an unusual form of carbon-non-radioactive ¹³C (an isotope) . After 10-30 minutes, she was asked to breathe into a receptacle, and her breath had been analyzed for the presence of this form of carbon in the carbon dioxide that she exhaled. You explain that the CO₂ she exhaled contained ¹³C, so

A) her test indicates the presence of H. pylori-the organism produces ammoniase that breaks down the ¹³C-containing urea that the patient swallowed into urea and CO₂ containing ¹³C which could be measured.
B) her test indicates the presence of H. pylori-the organism contains ¹³C in its cell wall, and in the presence of stomach acid, the cell wall is broken down to release CO₂ containing ¹³C which could be measured.
C) her test indicates the presence of H. pylori-the organism produces urease that breaks down the ¹³C-containing urea that the patient swallowed into ammonia and CO₂ containing ¹³C which could be measured.
D) her test indicates that her stomach cells used the ¹³C-containing urea in cellular respiration, producing glucose and releasing CO₂ containing ¹³C as a byproduct.
E) nobody really understands how the urea breath test works, but that it is well known that anybody who drinks urea containing ¹³C and exhales CO₂ containing this element afterwards needs treatment for an ulcer.