The Serum Chemistry Profile
5 Components:
1. Electrolytes / Acid-Base
2. Kidney
3. Glucose
4. Proteins
5. Muscle enzymes
6. Liver parameters
Liver Components
1. Enzymes
• SDH
• AST
• GGT
• SAP
2. Functional components
• BUN
• Glucose
• Albumin
• Iv. Bilirubin
Enzymes
Hepatocellular enzymes:
1. SDH
• Short half-life
• Cytosolic (means necrosis present)
• Liver specific
2. AST
• Intermediate half-life
• Cytosolic (means necrosis present)
• Not specific: also from muscle
Biliary:
1. GGT
• Very long half-life (several days) and upregulated
• Secreted (It means the ducts have been irritated/inflamed, Increase does not mean necrosis of cells)
• Biliary-specific (nearly...also found in pancreatic ducts)
2. SAP (serum alkaline phosphatase)
• Intermediate half-life
• Secreted (Increase means cells are irritated, not necessarily necrotic)
• Found in several other tissues:
• SAP also from bone, placenta, inflammatory cells...
Clinical Relevance
• SDH tells what is on-going (current status)
• GGT stays increased for weeks after insult
• SDH and GGT confer specificity
o indicate liver/biliary disease
• SDH and AST indicate hepatocellular necrosis
• GGT and SAP indicate biliary disease
Functional Indicators in the Chem Panel
These analytes are made by the liver:
Liver dysfunction / failure:
• BUN ↓ - except neonate
• Glucose ↓ – late finding
• Albumin ↓ – late finding; < 20 % of cases
• Cholesterol ↓
Bilirubin
• Indirect (unconjugated)
• Direct (conjugated)
One or both increase with liver disease
Direct fraction = 25 % of the total BR strong evidence of biliary disease