Which disease is primarily associated with elevated HVA and VMA in urine measured by HPLC?

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Multiple Choice

Which disease is primarily associated with elevated HVA and VMA in urine measured by HPLC?

Explanation:
Elevated urinary HVA (homovanillic acid) and VMA (vanillylmandelic acid) reflect increased turnover of catecholamines—dopamine, norepinephrine, and epinephrine. Neuroblastoma, a tumor of neural crest origin common in children, often secretes these catecholamines, so their breakdown products accumulate in urine. Measuring these metabolites by high-performance liquid chromatography in a 24-hour urine collection is a classic way to support diagnosis and monitor treatment for neuroblastoma. While pheochromocytoma also raises catecholamines, the standard diagnostic approach emphasizes metanephrines (plasma free metanephrines or urinary metanephrines) rather than HVA and VMA. Medullary thyroid carcinoma involves calcitonin, not catecholamine metabolites, and Wilms tumor does not characteristically affect catecholamine metabolism.

Elevated urinary HVA (homovanillic acid) and VMA (vanillylmandelic acid) reflect increased turnover of catecholamines—dopamine, norepinephrine, and epinephrine. Neuroblastoma, a tumor of neural crest origin common in children, often secretes these catecholamines, so their breakdown products accumulate in urine. Measuring these metabolites by high-performance liquid chromatography in a 24-hour urine collection is a classic way to support diagnosis and monitor treatment for neuroblastoma.

While pheochromocytoma also raises catecholamines, the standard diagnostic approach emphasizes metanephrines (plasma free metanephrines or urinary metanephrines) rather than HVA and VMA. Medullary thyroid carcinoma involves calcitonin, not catecholamine metabolites, and Wilms tumor does not characteristically affect catecholamine metabolism.

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