Test Details

• Discipline:

  Biochemistry

  Biochemistry

• Specimen Container Adult:

  Purple - EDTA

  Purple - EDTA

• Specimen Container Paediatric:

  Pink - EDTA

  Pink - EDTA

• Minimum Volume Adult:

  1 mL blood

  1 mL blood

• Minimum Volume Paediatric:

  1 mL blood

  1 mL blood

• Special Requirement:

  Avoid stress.

  Samples viable up to 30 min from collection without ice and for 60 mins with dry ice.

  Avoid stress.

  Samples viable up to 30 min from collection without ice and for 60 mins with dry ice.

• Sample Stability:

  EDTA plasma samples are stable at -20°C to -40°C for at least 6 months.

  EDTA plasma samples are stable at -20°C to -40°C for at least 6 months.

• Transport Requirements:

  Sample must be transported to the laboratory on dry ice within 30 mins of collection.

  For external laboratories, collected on dry ice and separtate within 30mins, sample must be stored and transpor...

  Sample must be transported to the laboratory on dry ice within 30 mins of collection.

  For external laboratories, collected on dry ice and separtate within 30mins, sample must be stored and transported frozen.

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• Quality Assurance:

  RCPA Quality Assurance Program

  RCPA Quality Assurance Program

• Interpretation:

  Plasma metanephrine or normetanephrine values greater than 4 times the upper reference interval are highly suggestive of the presence of phaeochromocytoma/paraganglioma. Elevated results are report...

  Plasma metanephrine or normetanephrine values greater than 4 times the upper reference interval are highly suggestive of the presence of phaeochromocytoma/paraganglioma. Elevated results are reported with appropriate comments.

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• Reference Ranges:

  Metanephrine:
  <1 year: <510 pmol/L
  Adult/Children ≥1yr: <510 pmol/L

  Normetanephrine:
  <3 months: <2540 pmol/L
  3 to <6 months: <2100 pmol/L
  6 months to 1yr: <1440 pmol/L
  Adult/Children ≥1yr: <1180 pmol/L
  
  3...

  Metanephrine:
  <1 year: <510 pmol/L
  Adult/Children ≥1yr: <510 pmol/L

  Normetanephrine:
  <3 months: <2540 pmol/L
  3 to <6 months: <2100 pmol/L
  6 months to 1yr: <1440 pmol/L
  Adult/Children ≥1yr: <1180 pmol/L
  
  3-methoxytyramine:
  <3 months: <420 pmol/L
  3 to <6 months: <330 pmol/L
  6 months to 1yr: <245 pmol/L
  Adult/Children ≥1yr: <180 pmol/L

  
  

  These reference ranges are based on a seated population. Ranges for samples taken in the supine posture are also now included on all reports.

  For a discussion of the issue of posture and relevant reference ranges please see our Plasma Metanephrines User Guide (available from link under Test Documents on this page).

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• Factors Affecting Result:

  Drugs can interfere analytically or pharmacodynamically with measurement of plasma or urinary metanephrines, potentially causing false positive results. The LC-MS/MS method for plasma free metaneph...

  Drugs can interfere analytically or pharmacodynamically with measurement of plasma or urinary metanephrines, potentially causing false positive results. The LC-MS/MS method for plasma free metanephrines is considered to be far less susceptible to analytical interference.

  Many drugs are now known to increase catecholamine and metabolite concentrations, including tricyclic antideppressant's, selective serotonin reuptake inhibitors, serotonin and noradrenaline reuptake inhibitors, α- and β- adrenergic receptor blockers, calcium channel blockers, monoamine oxidase inhibitors, Levo(L)-Dopa, methyldopa and several stimulant/sympathomimetic drugs.

  Ideally patients should discontinue all medications that may affect plasma and urinary catecholamine or metanephrine concentrations prior to sampling. In practice, it is not always possible to discontinue medication before testing and it might be better to repeat testing only when initial tests are elevated.

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• Other Info:

  Plasma metanephrine analysis is performed by HPLC-MS/MS.

  Plasma metanephrine analysis is performed by HPLC-MS/MS.

• Routine Contact Name:

  Duty Biochemist

• Routine Telephone:

  Freeman: 0191 244 8889
  RVI: 0191 282 9719

  Freeman: 0191 244 8889
  RVI: 0191 282 9719

• Routine Email:

  nuth.dutybiochemist@nhs.net

• Specialist Test:

  Yes

  Yes