- vanillylmandelic acid
- Misnomer for 4-hydroxy-3-methoxymandelic acid (α,3-dihydroxy-2-methoxybenzeneacetic acid); the major urinary metabolite of adrenal and sympathetic catecholamines ( e.g., from both epinephrine and norepinephrine); elevated in most patients with pheochromocytoma.
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van·il·lyl·man·de·lic acid .van-ə-.lil-man-.dē-lik- n a principal catecholamine metabolite C9H10O5 whose presence in excess in the urine is used as a test for pheochromocytoma abbr. VMA* * *
a metabolite of catecholamines excreted in abnormal amounts in the urine in conditions of excess catecholamine production, such as phaeochromocytoma. The measurement of VMA levels in a 24-hour urine sample is still used as a screening test for this condition, although this is being replaced by the direct measurement of urinary catecholamines. Urinary levels may be misleadingly high if foodstuffs with vanillin or the drug levodopa are taken before the test.* * *
va·nil·lyl·man·del·ic ac·id (və-nilґəl-mən-delґik) the primary end-product of catecholamine metabolism excreted in the urine; urinary levels are used in screening patients for pheochromocytoma. Abbreviated VMA.
Medical dictionary. 2011.
