Syncope, Vasovagal
Content 5
Determine Size by Ultrasound
Measure the diameter of the outside wall in a posterior-anterior direction and a right to left direction.
| < 5 cm | > 5 cm | Nondiagnostic |
Which of the following tests is the most sensitive for the diagnosis of bacterial overgrowth syndrome (of the GI tract)?
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The correct answer is B. You answered B.
The correct answer is "B." The d-xylose breath test takes advantage of the fact that the bacteria responsible for bacterial overgrowth syndrome (Gram-negative aerobes) catabolize d-xylose. The breath test measures radioactive CO2 that is formed as a result of bacterial breakdown of radioactive d-xylose. The glucose hydrogen breath test, in which glucose is administered to the patient and breath hydrogen is measured, is also helpful and commonly used. However, it is less sensitive and specific than the d-xylose test and has a 30% to 40% false-negative rate. Urea breath and CLO tests are tests for diagnosis of H. pylori, not small bowel bacteria overgrowth. See question 7.8.3.
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