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About This Test

Department: Biochemistry


Lithium heparin (green top)

Samples must be received on ice within 15 minutes of sampling

Add-on requests are not accepted


Turnaround Time:

Within 24 hours


Identification of hyperammonaemia, typically in patients with neurological symptoms or babies/infants with possible inherited metabolic disease

A free flowing blood sample should be collected, and transported directly to the laboratory. Samples must be received on ice within 15 minutes of sampling.

Spurious elevation of ammonia is common. All elevations should be confirmed with a repeat sample.

Reference ranges:

Age ranges Reference ranges (umol/L)
< 30 days < 100
< 16 years < 50
> 16 years (adults) < 40

Derived from (accessed January 2017)

Results outside the reference range do not necessarily indicate disease. Similarly, results within the reference range do not preclude abnormality. Please contact the Duty Biochemist for discussion of individual patient results.


Other Comments:

For more information, please see the following: Ammonia - Lab Tests Online

Content approved in Clinical Biochemists meeting 05.09.18