Specimen Collection

Serum/plasma samples must be separated within 6 hours. Separated specimens are

Sample stability:

• 12 hours at room temperature
• 48 hours at 2-8 ⁰ C
• 7 days at -20 ⁰ C.

4.5 mL PST Blood (Preferred)

0.5 mL Paediatric Micro-PST Blood (Preferred)

5 mL Heparin Blood

4 mL Plain Blood

3.5 mL SST Blood

0.5 mL Paediatric Microsample Blood

0.5 mL Paediatric Micro-heparin Blood
Reference Intervals

Units: mmol/L

After overnight fast, levels are usually <0.3 mmol/L.

After a 72h fast, levels range from 1 to 8 mmol/L in normal subjects.

Levels from 2 to 20 mmol/L are seen in diabetic ketoacidosis.

Uncertainty of Measurement: 8%

Turnaround Time: Within 3 hours
Assay Method

Principle: Colorimetric

Reagents: Randox RANBUT B-Hydroxybutyrate kit

Analyser: Cobas c502

Diagnostic Use and Interpretation

Betahydroxybutyrate is the prinicipal ketone in plasma. It is used for monitoring the treatment of diabetic ketoacidosis, and for detecting ketosis during fasting or hypoglycemia.

Beta-hydroxybutyrate is not detected by the dipstick test for ketones (which detects only acetoacetic acid).

See Ketones - urine

Contact Information

The chemical pathology team can be reached via email: chemicalpathologist@adhb.govt.nz or via Lablink (09) 307 4949 ext 22000 or 09-3078995

Emails will receive priority attention from the on-call chemical pathologist. Include the patients NHI.

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 Saku.Jayasinghe@adhb.govt.nz
• Dr Owen Yi WenyiYi@adhb.govt.nz

Last updated at 11:42:03 16/01/2026