Department

Biochemistry

Preferred Sample Type

Urine Metanephrines
24hr acidified urine

Sample Processing in Laboratory

Usual

Sample Preparation

The volume, dates & times of collection should be noted.

Turnaround Time

14

Sample Stability

4 oC

Urine Metanephrines

General Information

A phaeochromocytoma is a rare (0.1-1.0 % of hypertensive population), catecholamine-secreting tumor derived from chromaffin cells. When such tumors arise outside of the adrenal gland, they are termed extra-adrenal phaeochromocytomas, or paragangliomas. Because of excessive catecholamine secretion, phaeochromocytomas may precipitate life-threatening hypertension or cardiac arrhythmias. If the diagnosis of a phaeochromocytoma is overlooked, the consequences can be disastrous, even fatal; however, if a pheochromocytoma is found, it is potentially curable. Phaeochromocytomas are often associated with other endocrine tumours.

Symptoms of phaeochromocytoma are due to catecholamine excess and include:

  • Sustained or paroxysomal hypertension
  • Weight loss
  • Sweating
  • Headache
  • Palpitations
  • Anxiety

Since the secretion of the catecholamines, and hence the symptoms, from a phaeochromocytoma may be paroxysmal (i.e. short and frequent) it is recommended that 3 successive 24 hour urine collections are performed to 'catch' the catecholamine secretion and hence ensure the correct diagnosis.

The metabolites of the catecholamines - normetadrenaline and metadrenaline (collectively known as metadrenalines) - can also be used for the diagnosis of phaeochromocytoma, with their meaurement in both urine and plasma recommended for diagnosis at the First International Symposium on Phaeochromocytoma in 2005 due to their increased diagnostic specificity when compared to catecholamines.

Measurement of urinary catecholamines will also be performed on all samples.

 

 

Patient Preparation

Analyses are performed on 24 hour urine collections. Under exceptional circumstances block-timed urines and random specimens may be analysed. The 24 hour urines must be collected into acid (e.g. 50 mL of 3 mol/L hydrochloric acid); acidification of specimens following receipt by the laboratory is unacceptable.

Substances which can interfere both in vivo and in vitroinclude:

  • Tricyclic antidepressants
  • Phenoxybenzamine
  • Calcium channel blockers
  • Stimulants (e.g. caffeine, nicotine)
  • Levodopa
  • Paracetamol

Patietns should avoid caffeine for 24 hours and during collection of your specimen. In addition, the following drugs should be avoided for one week prior to the collection, if clinically feasible:

Phenothiazines (used to treat mental or emotional disorders)
Tricyclic antidepressants including imipramine, as well as labetalol, sotalol and monoamine oxidate inhibitors (MAOIs)
Chlorpromazine (used to treat psychosis)

Notes

For interpretation contact duty biochemist (bleep 2506)

Reference Range

 

Table 1. 24hr Urine Metadrenaline Ranges

Analyte

Age

Collection

µmol/ 24 hr

Source

Normetadrenaline

Adult

24 hr

<4.9

Locally derived

0-2 months

24 hr

<0.85

Tietz

3-5 months

24 hr

<0.61

6-8 months

24 hr

<0.6

9-11 months

24 hr

<0.56

1yr

24 hr

<0.65

2-5 yr

24 hr

<0.6

6-9 yr

24 hr

<0.96

10-15 yr

24 hr

<1.59

Metadrenaline

Adult

24 hr

<2.0

Tietz

0-2 months

24 hr

<0.19

3-8 months

24 hr

<0.21

9-11 months

24 hr

<0.51

1 yr

24 hr

<0.26

2-5 yr

24 hr

<0.5

6-9 yr

24 hr

<0.7

10-15 yr

24 hr

<1.23

3 MT

Adult

24 hrs

<2.75

Measurement of urinary metanephrines   to screen for pheochromocytoma in an unselected hospital referral   population. Shine   Bet al. Clin Chem 2006 Nov;52(11):2060-4. Epub 2006 Sep 21

0- 4 years

24 hrs

<0.62

Paediatric   Reference Values for Urinary Catecholamine Metabolites Evaluated by High

Performance Liquid   Chromatography and Electrochemical Detection1

5-15 years

24 hrs

<1.26


                        Table 2. Random Urine Metadrenaline Ranges

 Analyte  Age  Collection  umol/mmol creatinine

Source

Normetadrenaline

Adult

Random

<0.35

Locally derived

0-2 months

Random

<1.32

Chromsystems Dialog Magazine, 2009,   http://chromsystems.com/en-gb/news/dialog

3-5 months

Random

<0.91

6-11 months

Random

<0.57      

1yr

Random

<0.35

2-4 yr

Random

<0.24

5-9 yr

Random

<0.16

10-15 yr

Random

<0.11

Metadrenaline

Adult

Random

<0.11

Locally derived

0-5 months

Random

<0.21

Chromsystems Dialog Magazine, 2009,   http://chromsystems.com/en-gb/news/dialog

6-11 months

Random

<0.13

1 yr

Random

<0.12

2-4 yr

Random

<0.11

5-9 yr

Random

<0.10

10-15 yr

Random

<0.07

3MT

Adult

Random

<0.15

Locally derived

<1yr

Random

<1.5

Annales de Biologie Clinique. Volume   60, Numéro 1, 15-36, Janvier - Février 2002

1 yr

Random

<0.75

2-15 yr

Random

<0.36

 

 

Source of Reference Range

Clinical Guide to Laboratory Tests, 3rd Edition, Teitz, 1995 ISBN 0-7216-5035-X and local validation

Specifications

  • EQA Scheme?: Yes
  • EQA Status: NEQAS

The laboratories at Heartlands Hospital, Good Hope Hospital and Solihull Hospital form part of the services provided by University Hospitals Birmingham and are UKAS (United Kingdom Accreditation Service) accredited to the ISO 15189:2012 standard. For a list of accredited tests and other information please visit the UKAS website using the following link: https://www.ukas.com/find-an-organisation/

  • Heartlands, Good Hope and Solihull Hospital pathology laboratories are a UKAS accredited medical laboratory No.8217
  • United Kingdom Health Security Agency laboratory is a UKAS accredited medical laboratory No.8213

Tests not appearing on the UKAS Schedule of Accreditation currently remain outside of our scope of accreditation. However, these tests have been validated to the same high standard as accredited tests and are performed by the same trained and competent staff.

For further test information, please visit the test database: http://www.heftpathology.com/frontpage/test-database.html.

Protection of personal information - Laboratory Medicine comply with the Trust Data Protection policy and have procedures in place to allow the Directorate and its employees to comply with the Data Protection act  1998 and associated best practice and guidance.

For further information contact Louise Fallon, Quality Manager, 0121 424 1235

UKAS HEFT