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)
MetanephrinesLess than 0.5 nmol/L
NormetanephrinesLess 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 UnitsSI Units (Conventional Units × 5.2)Conventional UnitsSI Units (Conventional Units × 5.2)
Age/MaleAge/Female
  3–8 yr29–92 mcg/24 hr151–478 micromol/day18–144 mcg/24 hr94–749 micromol/day
  9–12 yr59–188 mcg/24 hr307–978 micromol/day43–122 mcg/24 hr224–634 micromol/day
  13–17 yr69–221 mcg/24 hr359–1149 micromol/day33–185 mcg/24 hr172–962 micromol/day
  18 yr and older44–261 mcg/24 hr229–1357 micromol/day30–180 mcg/24 hr156–936 micromol/day
Normetanephrines, Fractionated (normal BP)Conventional UnitsSI Units (Conventional Units × 5.5)Conventional UnitsSI Units (Conventional Units × 5.5)
Age/FemaleAge/Male
3–8 yr34–169 mcg/24 hr187–930 micromol/day29–145 mcg/24 hr160–798 micromol/day
9–12 yr84–422 mcg/24 hr462–2321 micromol/day55–277 mcg/24 hr302–1524 micromol/day
13–17 yr91–456 mcg/24 hr501–2508 micromol/day57–286 mcg/24 hr314–1573 micromol/day
Conventional UnitsSI Units (Conventional Units × 5.5)
Age/Male and Female
18–29 yr103–390 mcg/24 hr566–2145 micromol/day
30–39 yr111–419 mcg/24 hr610–2304 micromol/day
40–49 yr119–451 mcg/24 hr654–2481 micromol/day
50–59 yr128–484 mcg/24 hr704–2662 micromol/day
60–69 yr138–521 mcg/24 hr759–2866 micromol/day
70 yr and older148–560 mcg/24 hr814–3080 micromol/day

Critical Findings and Potential Interventions
N/A

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