Metanephrines, Blood and Urine

General

Synonym/Acronym:
N/A

Rationale
To assist in the diagnosis of cancer of the adrenal medulla (e.g., catecholamine-secreting tumors, such as pheochromocytoma [a benign tumor of the adrenal gland] and neuroblastoma [a rare tumor that most often originates in the nervous tissue of the adrenal medulla]) or to assess for the cause of hypertension.

Patient Preparation
There are no food, fluid, or medication restrictions unless by medical direction. Patients should have their blood drawn for plasma-free metanephrines, while in a supine position. Instruct the patient to avoid excessive exercise and stress during the 24-hr collection of urine. Usually a 24-hr urine collection may be ordered. As appropriate, provide the required urine collection container and specimen collection instructions.

Normal Findings
Method: Liquid chromatography tandem mass spectrometry.

Blood (supine)
Metanephrines Less than 0.5 nmol/L
Normetanephrines Less than 0.9 nmol/L
Note: Values should be compared to reference intervals determined from the same collection position.
24-hr Urine
Metanephrines, Fractionated (normal BP) Conventional Units SI Units (Conventional Units × 5.2) Conventional Units SI Units (Conventional Units × 5.2)
Age Male Female
7–12 yr45–273 mcg/24 hr234–1,420 micromol/day40–209 mcg/24 hr208–1,087 micromol/day
13–17 yr56–298 mcg/24 hr291–1,550 micromol/day40–209 mcg/24 hr208–1,087 micromol/day
18 yr and older55–320 mcg/24 hr286–1,664 micromol/day36–229 mcg/24 hr187–1,191 micromol/day
Normetanephrines, Fractionated (normal BP) Conventional Units SI Units (Conventional Units × 5.5) Conventional Units SI Units (Conventional Units × 5.5)
Age Male Female
7–12 yr58–670 mcg/24 hr319–3,685 micromol/day48–474 mcg/24 hr264–2,607 micromol/day
13–17 yr82–553 mcg/24 hr451–3,042 micromol/day65–406 mcg/24 hr358–2,233 micromol/day
18–29 yr81–667 mcg/24 hr446–3,668 micromol/day
18 yr and older 95–650 mcg/24 hr522–3,575 micromol/day
30 yr and older114–865 mcg/24 hr627–4,758 micromol/day

Critical Findings and Potential Interventions
N/A

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