asymptomatic raised alkaline phosphatase
Last edited 09/2019 and last reviewed 10/2023
The elevation of alkaline phosphatase levels in an asymptomatic individual should be confirmed by anlysis of a repeat blood sample.
Chronic elevation of alkaline phosphatase levels in an otherwise well individual may be:
- a variant of normal
- due to bone disease
- due to liver disease:
- liver disease is supported by elevated gamma-GT levels
Sometimes it is useful to look at the relationship of ALP to bilirubin and lactate dehydrogenase (LD) levels (1)
| Pathology | Alkaline Phosphatase | Bilirubin | LD |
| Intra or extrahepatic cholestasis | Increased | Increased | Normal |
| Focal benign cholestasis | Increased | Normal | Normal |
| Focal malignant cholestasis | Increased | Normal | Increased |
Notes:
-
if alkaline phosphatase is raised in an asymptomatic patient and serum bilirubin, liver transaminases, creatinine, adjusted calcium, thyroid function, and blood count are normal (2):
- consider growth spurts in adolescents, pregnancy in women, drugs, and age related increases
- as most likely sources are either bone or liver, differentiate by measuring GGT (raised in liver) and investigate accordingly
- for liver cases investigate with abdominal ultrasound scan (cholestasis and hepatic space occupying lesion) and antimitochondrial antibodies (primary biliary cirrhosis)
- for bone cases investigate vitamin D
Reference:
elevation of ALP in normal individuals
bone diseases causing asymptomatic elevation of ALP
liver diseases causing asymptomatic elevation of ALP
investigation of asymptomatic raised alkaline phosphatase