From the Guidelines
Alkaline phosphatase (ALP) is elevated in various conditions, including liver diseases such as cholestatic liver disease, cirrhosis, and liver infiltrative diseases, as well as bone diseases like Paget's disease and osteomalacia, and other conditions such as pregnancy, growth spurts in children and adolescents, certain cancers, sepsis, hyperthyroidism, and inflammatory bowel diseases 1.
Conditions Associated with Elevated ALP
Some of the key conditions associated with elevated ALP levels include:
- Liver diseases:
- Cholestatic liver disease, such as primary biliary cholangitis and primary sclerosing cholangitis
- Cirrhosis
- Liver infiltrative diseases, such as sarcoidosis and amyloidosis
- Hepatitis
- Liver metastases
- Bone diseases:
- Paget's disease
- Osteomalacia
- Rickets
- Healing fractures
- Bone tumors
- Hyperparathyroidism
- Other conditions:
- Pregnancy
- Growth spurts in children and adolescents
- Certain cancers, especially with bone metastases
- Sepsis
- Hyperthyroidism
- Inflammatory bowel diseases
- Medications like certain antibiotics and anticonvulsants
Determining the Underlying Cause
The pattern of ALP elevation, along with other liver enzymes and clinical context, helps determine the underlying cause, with elevated GGT levels often indicating a hepatic origin of ALP elevation 1.
Clinical Considerations
In clinical practice, ALP measurements should be interpreted in conjunction with other liver tests and clinical history to determine the underlying cause of elevation 1.
Key Takeaways
- ALP elevations can occur in a variety of conditions affecting the liver, bones, and other organs
- The pattern of elevation and clinical context are crucial in determining the underlying cause
- Elevated GGT levels often indicate a hepatic origin of ALP elevation
- ALP measurements should be interpreted in conjunction with other liver tests and clinical history to determine the underlying cause of elevation 1
From the Research
Conditions Associated with Elevated Alkaline Phosphatase
Elevated alkaline phosphatase (ALP) levels can be associated with various conditions, including:
- Bone involvement from malignancy or Paget's disease 2
- Sepsis, which can cause extremely high ALP levels even with normal bilirubin levels 2
- Biliary obstruction, including malignant obstruction and common bile duct stones 2
- Acquired immunodeficiency syndrome (AIDS) 2
- Diffuse liver metastases 2
- Benign intrahepatic disease, such as liver hemangiomas, sarcoid hepatitis, lead toxicity, and drug-induced cholestasis 2
- Underlying malignancy, including infiltrative intrahepatic malignancy, bony metastasis, and both hepatic and bone metastasis 3
- Bone disease, including osteomalacia and Paget's disease 3, 4
- Unsuspected parenchymal liver disease and non-malignant infiltrative liver disease 3
- Chronic renal failure and renal damage, which may cause increased ALP levels due to injury to the brush border membrane of the renal tubular cells 5, 6
- Femoral fractures, which can cause a rise in ALP levels due to bone healing 5
Specific Conditions and ALP Levels
Certain conditions can cause extremely high ALP levels, including:
- Sepsis, which can cause ALP levels above 1,000 U/l 2
- Malignant obstruction, which can cause extremely high ALP levels 2
- AIDS, which can cause elevated ALP levels due to various opportunistic infections and conditions 2
- Paget's disease, which can cause highly elevated ALP levels, often correlated with bone alkaline phosphatase (B-ALP) levels 4
- Primary hyperparathyroidism, which can cause increased B-ALP levels 4
- Chronic renal failure, which can cause increased ALP levels due to renal damage 6