Alkaline phosphatase

The role of alkaline phosphatase (ALP) in the body

Alkaline phosphatase is an enzymeEnzymes are proteins that accelerate chemical reactions in the body. They ensure the occurrence of metabolic processes such as food digestion, energy release, cell formation, and many others. involved in phosphorus-calcium metabolism. . The highest concentrations are found in:

• Liver cells(hepatocytesHepatocytes are the main cells of the liver. They account for 60 to 80% of the mass of the entire organ. These are the main functional units of the liver, involved in a wide range of physiological processes such as nutrient metabolism, protein synthesis, detoxification, and bile secretion.)
• Bones (osteoblasts)
• Placenta (in pregnant women)
• The intestines

Main functions:

1. Bone mineralization (cleavage of phosphates for calcium absorption)
2. Bile acid metabolism (hepatic form)
3. Placental growth during pregnancy
4. Fat metabolism in the gut

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Group	Reference range (U/L)
Adults	30–120
Children	150–500 (active bone growth)
Pregnant women	Up to 250

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Reduced alkaline phosphatase (Hypophosphatazemia)

Main reasons:

• Hypothyroidism
• Anemia (B12-, folate-deficient)
• Hereditary hypophosphatazemia (a rare genetic disorder)
• Zinc/Magnesium deficiency

Symptoms:

• Muscle weakness
• Bone deformities (in children)
• Premature tooth loss
• Respiratory disorders (in severe cases)

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Elevated alkaline phosphatase (Hyperphosphatazemia)

Critical levels:

• > 500 U / L – suspected Paget’s disease
• > 1000 U / L – biliary tract obstruction

Main reasons:

1. Liver diseases (hepatitis, cirrhosis, cholestasis)
2. Bone diseases (osteoporosis, metastases)
3. Hyperparathyroidism
4. Kidney/lung infarction

Symptoms:

• Jaundice, pruritus of the skin(with cholestasis)
• Bone pain
• Frequent fractures
• Nausea, loss of appetite (with hepatic pathologies)

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What should I do if there are deviations?

With an increase in alkaline phosphatase:

1. Liver tests (ALT, AST, bilirubin)
2. Calcium/phosphorus analysis
3. Ultrasound of the liver and biliary tract
4. X-ray of bones (if Paget’s disease is suspected)

When the ALP is lowered:

1. Thyroid HormonesHormones are biologically active substances that are produced by specialized cells or glands (such as endocrine glands) and regulate various physiological processes in the body. They act as chemical signals that are transmitted through the bloodstream to organs and tissues to control and coordinate a wide range of functions, including metabolism, growth and development, reproduction, mood, and more. Examples include insulin, testosterone, estrogen, and adrenaline. (TTG, T4)
2. Vitamins B12 and Folate
3. Genetic test (for inherited forms)

Important: Children have a high level of ALP- norm (active growth of the skeleton)! In adults, an increase always requires diagnosis.