Specimen Collection

Sample stability:

• 7 days at 15-25 ^o C
• 7 days at 2-8 ^o C
• 1 year at -20 ^o C

4.5 mL Adult PST Blood (Preferred)

0.5 mL Paediatric Micro-PST Blood (Preferred)

5 mL Adult Heparin Blood

4 mL Adult Plain Blood

5 mL Adult SST Blood

0.5 mL Paediatric Microsample Blood

0.5 mL Paediatric Micro-heparin Blood
Reference Intervals

urea (mmol/L)
Neonate:	1.0 - 4.0
1 month - 1 yr:	1.4 - 5.4
1 yr - 4 yr:	1.8 - 5.4
Adult:	3.2 - 7.7

Uncertainty of Measurement: 6%

Turnaround Time: Within 3 hours
Assay Method

Principle : Enzymatic

Reagents: Roche Urea Kit

Analyser: Cobas c702

Diagnostic Use and Interpretation

Plasma urea may be used as a rough index of renal function, although creatinine is a better index of glomerular filtration.

Urea is synthesised in the liver from amino acids and its level is dependent on protein intake. Urea rises proportionately more than creatinine in dehydration or pre-renal uremia.

Contact Information

Emails to chemicalpathologist@adhb.govt.nz will receive priority attention from the on-call chemical pathologist.

If the query concerns a specific patient please include the NHI number in your email.

If email is not a suitable option, please contact the on-call chemical pathologist via Lablink (Auckland City Hospital ext. 22000 or 09-3078995).

Individual chemical pathologists may be contacted but will not be available at all times.

After-hours : contact Lablink (Auckland City Hospital ext. 22000 or 09-3078995) or hospital operator for on duty staff after hours.

Dr Samarina Musaad (Clinical Lead) : SamarinaM@adhb.govt.nz ext. 22402

Dr Cam Kyle: CampbellK@adhb.govt.nz ext 22052

Dr Weldon Chiu: WeldonC@adhb.govt.nz ext. 23427

Dr Campbell Heron: CHeron@adhb.govt.nz ext. 23427

Dr Sakunthala Jayasinghe: Sakunthala@adhb.govt.nz ext. 23427

Last updated at 15:26:00 06/01/2025