Question

Laboratory diagnosis of Chronic Liver Disease.

Hint:

Liver function tests, viral hepatitis markers, and autoimmune markers are critical for diagnosing and identifying the etiology of chronic liver disease.

Answer 1

The laboratory diagnosis of chronic liver disease (CLD) involves a combination of tests to assess liver function, identify the cause of the disease, and assess the degree of liver damage.
1. Liver Function Tests (LFTs):
- AST (Aspartate Aminotransferase) and ALT (Alanine Aminotransferase): These enzymes are released into the bloodstream when liver cells are damaged. ALT is more specific to the liver, while AST may also be elevated in conditions involving other organs.
- Alkaline Phosphatase (ALP): Elevated in cholestatic liver disease, biliary obstruction, or cirrhosis.
- Bilirubin: Elevated levels of total bilirubin may indicate liver dysfunction, as seen in cirrhosis or hepatocellular injury.
- Albumin: Decreased levels of albumin are seen in advanced liver disease, as the liver's ability to synthesize proteins is impaired.
2. Viral Hepatitis Markers:
- Hepatitis B (HBV): Presence of HBsAg (Hepatitis B surface antigen) indicates an ongoing infection, while anti-HBc (Hepatitis B core antibody) and anti-HBs (Hepatitis B surface antibody) help assess immunity or past infection.
- Hepatitis C (HCV): Detection of anti-HCV antibodies and HCV RNA indicates an active or past infection. The HCV genotype helps guide treatment decisions.
3. Autoimmune Markers:
- Anti-nuclear antibodies (AN: Positive in autoimmune liver diseases like autoimmune hepatitis.
- Anti-smooth muscle antibodies (ASM: Associated with autoimmune hepatitis.
- Immunoglobulin levels: Elevated immunoglobulin G (IgG) levels are common in autoimmune hepatitis.
4. Alpha-1 Antitrypsin Levels:
- Alpha-1 antitrypsin deficiency can cause cirrhosis in children and adults. Low levels of this enzyme are associated with liver damage.
5. Serum Ferritin and Transferrin Saturation:
- Elevated serum ferritin and transferrin saturation can indicate hemochromatosis, a condition causing iron overload in the liver.
6. Prothrombin Time (PT):
- Prolonged PT or INR (international normalized ratio) indicates impaired liver function and synthetic capacity, often seen in cirrhosis.