NHA Certified Clinical Medical Assistant (CCMA)Clinical Patient CareMedium
A medical assistant is preparing to perform a fecal occult blood test (FOBT) using a guaiac card. Which of the following foods should the MA instruct the patient to avoid for several days prior to the test?
- AChicken
- BRed meat
- CBroccoli
- DPasta
Show answer & explanationAnswer & explanation
Correct answer: B. Red meat
Red meat contains hemoglobin, which can cause a false-positive result on a guaiac-based FOBT, as the test detects the peroxidase activity of hemoglobin. Patients are typically advised to avoid red meat for at least 3 days before and during the collection period. Other foods like chicken, broccoli, and pasta do not typically interfere with the test.
Why the other options are wrong
- A. Chicken does not typically interfere with guaiac FOBT results.
- C. Broccoli, while a vegetable, does not contain hemoglobin and is generally not restricted for guaiac FOBT.
- D. Pasta does not typically interfere with guaiac FOBT results.
Fecal Occult Blood Test (FOBT) Restrictions
Dietary and medication restrictions necessary before a guaiac-based FOBT to prevent false-positive or false-negative results.
- Avoid red meat for 3 days prior.
- Avoid certain raw fruits/vegetables (e.g., turnip, radish, horseradish) for 3 days prior.
- Avoid vitamin C supplements for 3 days prior (can cause false negatives).
- Avoid aspirin, NSAIDs for 7 days prior (can cause GI bleeding).
Memory trick: No Red, No Raw, No Rx, No C