Alkaline Phosphatase (ALP)

Clinical use: The reference range is approximately trebled in the third trimester of pregnancy.
Raised during puberty (bone growth).
Raised in bone disease.
Raised in liver disease.
Background: Alkaline Phosphatase (ALP) is the name given to a group of enzymes that remove phosphate groupings from a variety of substrates at an alkaline pH. If the pH is maintained at 10.5 at room temperature, the reactions can be made practically specific for those ALP isoenzymes found in the liver, bone or placenta.The most usual reason for ALP determination is as a liver function test.

Very high levels are found in Paget’s disease and obstructive jaundice, whilst moderate elevations are found in the infective liver diseases, cirrhosis and tumours of the liver.

In the adolescent slight increases are found due to rapid bone production, but in this case ALP electrophoresis demonstrates that the bone isoenzyme is present.

Reference ranges: Up to 14 days: 60 – 350 u/L
Associated diseases:
Patient preparation:
Specimen requirements: Serum or Lithium Heparin Plasma
Turnaround time: 2 hours
Additional information:
Referred test: