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Mayo Test Catalog, (Sorted By Test Name) - Mayo Medical ...

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HVAR<br />

60275<br />

HUNY<br />

82373<br />

<strong>Medical</strong>. Edited by N Blau, M Duran, ME Blaskovics. London, UK. 1996, pp 79-98 2. Hyland K:<br />

Presentation, diagnosis, and treatment of the disorders of monoamine neurotransmitter metabolism. Sem<br />

Perinatol 1999;23:194-203 3. Strenger V, Kerbl R, Dornbusch HJ, et al: Diagnostic and prognostic<br />

impact of urinary catecholamines in neuroblastoma patients. Pediatr Blood Cancer 2007;48:504-509<br />

Homovanillic Acid (HVA), Random, Urine<br />

Clinical Information: Homovanillic acid (HVA) and other catecholamine metabolites<br />

(vanillylmandelic acid [VMA] and dopamine) are typically elevated in patients with<br />

catecholamine-secreting tumors (eg, neuroblastoma, pheochromocytoma, and other neural crest tumors).<br />

HVA and VMA levels may also be useful in monitoring patients who have been treated as a result of the<br />

above-mentioned tumors. HVA levels may also be altered in disorders of catecholamine metabolism;<br />

monamine oxidase-A deficiency can cause decreased urinary HVA values, while a deficiency of<br />

dopamine beta-hydrolase (the enzyme that converts dopamine to norepinephrine) can cause elevated<br />

urinary HVA values.<br />

Useful For: Screening children for catecholamine-secreting tumors Monitoring neuroblastoma<br />

treatment Screening patients with possible inborn errors of catecholamine metabolism<br />

Interpretation: Vanillylmandelic acid and/or homovanillic acid (HVA) concentrations are elevated in<br />

over 90% of patients with neuroblastoma; both tests should be performed. A positive test could be due to<br />

a genetic or nongenetic condition. Additional confirmatory testing is required. A normal result does not<br />

exclude the presence of a catecholamine-secreting tumor. Elevated HVA values are suggestive of a<br />

deficiency of dopamine beta-hydrolase, a neuroblastoma, a pheochromocytoma, or may reflect<br />

administration of L-dopa. Decreased urinary HVA values may suggest monamine oxidase-A deficiency.<br />

Reference Values:<br />

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