Turnaround times
The quoted turnaround time is from sample receipt in the laboratory, to results authorisation in the Laboratory Information Management system. The times do not include transport of specimen to the laboratory or the administrative process to print and post/email reports. Service users must allow for transport and reporting time when ordering tests.
Clinical background:
Gamma-glutamyl transferase (GGT) is an enzyme found mainly in the liver. When the liver is injured or the flow of bile is obstructed, the concentration of GGT within the bloodstream rises. It is therefore a useful marker for detecting liver disease and bile duct injury. It can help find out the reason for a raised concentration of alkaline phosphatase (ALP) within the bloodstream. Both ALP and GGT are elevated in disease of the bile ducts and in some liver diseases, but only ALP will be elevated in bone disease. If the GGT concentration is normal in a person with a high ALP result, the cause is most likely to be bone disease. GGT can also be used to screen for alcohol abuse. Several drugs increase (induce) the concentration of GGT in the blood. The increases do not indicate damage to the liver.
Specimen container paediatric:
Serum (SST or plain tube)
Specimen container adult:
Serum (SST or plain tube)
Minimum volume paediatric:
0.5 mL blood
Minimum volume adult:
1 mL blood
Sample stability:
Unseparated sample: 24 hours
Separated sample:
7 days at 15 to 25°C,
7 days at 2 to 4°C,
1 year at -20°C
Reference ranges:
Up to 3 months: 0 – 200 IU/L
3 to 6 months: 0 – 150 IU/L
6 months and over (Male): 0 – 70 IU/L
6 months and over (Female): 0 – 45 IU/L
Other info:
Lithium heparin plasma sample also acceptable