Dietary flavonols contribute to false-positive elevation of homovanillic acid, a marker of catecholamine-secreting tumors

作者：Combet Emilie; Lean Michael E J^*; Boyle James G; Crozier Alan; Davidson D Fraser

来源：Clinica Chimica Acta, 2011, 412(1-2): 165-169.

DOI：10.1016/j.cca.2010.09.037

• Homovanillic acid
• HVA
• Mass spectrometry
• Phaeochromocytoma
• Catecholamine
• Flavonols
• Diet
• Interference
• False-positives

Background: Urinary homovanillic acid (HVA) measurement is used routinely as a marker of the first test for the screening of catecholamine-secreting tumors and dopamine metabolism, but generates a large number of false-positive results. With no guidelines for dietary restrictions prior to the test, we hypothesize that consumption of flavonol-rich foods (such as onions, tomatoes, tea) prior to urinary catecholamine screening could be responsible for false-positive urinary HVA in healthy subjects.
Methods: A randomized, crossover dietary intervention was carried out in healthy subjects (n = 17). Volunteers followed either a low or high-flavonol diet, for a duration of 3 days, prior to providing a 24-h urine sample for HVA measurement using a routine, validated liquid chromatography method as well as a gas chromatography-mass spectrometry method.
Results: Dietary flavonol intake significantly increased urinary HVA excretion (p<0.001), with 3 out of 17 volunteers (20%) exceeding the 40 mu mol/24 h upper limit of normal for HVA excretion (false-positive result).
Conclusion: Dietary flavonols commonly found in foodstuff such as tomatoes, onions, and tea, interfered with the routine urinary HVA screening test and should be avoided in the three-day run-up to the test.

• 出版日期2011-1-14