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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
In Pheochromocytoma, which of the following is increased in urine?
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The correct answer is  a. VMA(Ref: Nelson's 20/e p 2227-2729, Ghai 8/e p 525)Biochemical tests for Pheochromocytoma:Pheochromocytomas synthesize and store catecholamine, so elevated plasma and urinary levels of catecholamines methylated metabolites (VMA or vanillyl mandelic acid), metanephrines, are the cornerstone for the diagnosisAmong these tests, the fractionated metanephrines and catecholamines are the most sensitive.QIn contrast to adults with pheochromocytoma in whom both norepinephrine and epinephrine are elevated, children with pheochromocytoma predominantly excrete norepinephrine in the urine.