Synonyms

ALP

Part of Profile

Liver Function Test, Bone.

Clinical Indications

ALP rises in the presence of bile duct obstruction (e.g. primary biliary cirrhosis, gallstones, bile duct strictures). 
ALP is also elevated in bone disease where increased osteoblastic activity is involved (e.g. malignancy (not myeloma), osteomalcia, pagets) 

Request Form

Combined Pathology Blood form (Yellow/Black)

Availability

On request

Turnaround Time

Same day.

Specimen

Serum

Volume

2 ml

Container

Yellow top (SST) tube

Collection

No specific collection conditions

Causes for Rejection

Unlabelled specimen

Reference range

Adult: 30 - 130 IU/L. Mild increases in ALP may be seen as a result of age-related changes, particularly in older women.
Children: 30 - 350 IU/L. Levels is children may be mildly elevated during growth spurts.

Interpretation

Elevated ALP may be as a result of liver or bone disease. Certain medications may also cause rises in ALP. A normal gamma-GT may be used to exclude liver disease, but a raised gamma-GT does not exclude bone disease (since liver and bone disease may both be present).
In bone disease,  particularly high levels of ALP are seen in Paget's disease. It should be noted that rises in ALP are not seen in osteoporosis or myeloma as increased osteoblastic activity is not involved.
High levels of ALP may be due to transient hyperphosphatasaemia of childhood, which can occur in younger adults. Alkaline phosphatase isoenzyme analysis is indicated.

Critical Difference

22 IU/L