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Alkaline phosphatase - total

Clinical significance

1) Physiologic changes in the catalytic concentration of AP in serum
A) Physiologic increase in the catalytic activity of AP
During the third trimester of gestation, the catalytic activity of AP reaches the upper reference value (normal value). Its values return to normal in 3-6 weeks postpartum. The increase in the catalytic activity of AP in pregnancy results from the transfer of AP from the placenta to the serum/plasma and from the increase in the hepatic AP enzyme.
B) Physiologic decrease in the catalytic activity of AP
a) protein-rich diet
b) physical exertion

2) Pathologic changes in the catalytic concentration of AP in serum
A) Increased serum AP catalytic activity values
a) Liver diseases

Increased AP catalytic activity is frequently associated with an increase in the catalytic activity of AST and bilirubin concentration.
- Significantly increased in:
• biliary cirrhosis,
• cholangitis,
• Crohn’s disease,
• fatty liver,
• heart failure,
• infectious jaundice,
• liver metastases,
• obstructive jaundice.
- Moderately increased in:
• acute hepatitis,
• chronic hepatitis.
• liver cirrhosis,
b) Bone disease
- Significantly increased in:

• bone fracture,
• bone metastases,
• Cushing’s syndrome,
• osteogenic sarcoma,
• Paget’s disease.
- Moderately increased in:
• osteomalacia,
• rickets
c) Pancreatic disease
• acute pancreatitis,
• carcinoma of the pankreas,
• chronic pancreatitis,
• diabetes mellitus (some cases),
d) Renal disease
• nephrosis,
• renal tubular acidosis,
• renal tubular defects
• transplanted kidney rejection,
e) Heart diseases
• myocardial infarction.
f) Other diseases
• acromegaly,
• hyperparathyroidism,
• Hodgkin’s lymphoma,
• infectious mononucleosis,
• leukemia,
• non-Hodgkin’s lymphoma.
g) Enzyme induction
• alcohol,
• barbiturates,
• phenytoin
h) Other
• oral contraceptives.

B) Decreased serum AP catalytic activity values
• achondroplasia,
• clofibrate therapy,
• cretinism,
• deposit of radioactive substances in bone,
• hypophosphatasaemia,
• hypothyroidism,
• kwashiorkor,
• malnutrition,
• milk-alkali syndrome,
• pernicious anemia,
• placental insufficiency,
• scurvy.