metabolites of the hormones adrenaline and noradrenaline, respectively. Both hormones are released in excess from a *phaeochromocytoma, and measurement of their metabolites is the most reliable screening test for this rare but potentially lethal condition. The test is best carried out on a complete 24-hour urine collection.
(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in a 24-hour urine sample was formerly used as a screening test for this condition, but in the UK it has been largely superseded by the urinary metanephrine test (see metanephrine and normetanephrine).... vanillylmandelic acid
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