An Overnight Fast Is Recommended for Individuals Being Tested for Carcinoid

question 15

Multiple Choice

An overnight fast is recommended for individuals being tested for carcinoid syndrome because:

• A) dietary interference,particularly with foods that contain 5-hydroxyindoles,will produce a false increase in plasma 5-HIAA measurement.
• B) no food should be present in the GI tract for 12 hours before analysis of catecholamine metabolites.
• C) monoamine systems are targets of certain components of foods that contain tyrosine,and a false-negative result will occur in HVA testing.
• D) certain foods interfere with the methods of analysis used for serotonin analysis,particularly the high performance liquid chromatography (HPLC)assays.