What laboratory finding is a hallmark of hemolytic anemia?

What laboratory finding is a hallmark of hemolytic anemia?

• A. Direct bilirubin
• B. Indirect bilirubin
• C. ALT
• D. ALP

Answer: (B)

When red blood cells are destroyed in hemolytic anemia, heme is released and broken down to bilirubin. The liver conjugates bilirubin to make direct (conjugated) bilirubin, but in hemolysis the production of unconjugated bilirubin outpaces the liver’s ability to conjugate it, so indirect (unconjugated) bilirubin rises. Direct bilirubin tends to stay normal in isolated hemolysis unless there’s another liver problem. ALT and ALP reflect liver injury or biliary disease, not the primary issue in hemolysis, so they aren’t the hallmark.

When red blood cells are destroyed in hemolytic anemia, heme is released and broken down to bilirubin. The liver conjugates bilirubin to make direct (conjugated) bilirubin, but in hemolysis the production of unconjugated bilirubin outpaces the liver’s ability to conjugate it, so indirect (unconjugated) bilirubin rises. Direct bilirubin tends to stay normal in isolated hemolysis unless there’s another liver problem. ALT and ALP reflect liver injury or biliary disease, not the primary issue in hemolysis, so they aren’t the hallmark.