Which laboratory test results would indicate a hemolytic process in a patient with anemia?

A hemolytic process in anemia can be indicated by specific laboratory findings. Among these, elevated lactate dehydrogenase (LDH) and decreased haptoglobin are particularly significant markers.

When red blood cells are destroyed (hemolysis), LDH, which is released from damaged red blood cells, increases in the bloodstream. This indicates that there is significant cellular breakdown occurring. Conversely, haptoglobin, a protein that binds free hemoglobin released from lysed red blood cells, typically decreases during hemolysis because it gets consumed in the process of binding the free hemoglobin. Therefore, elevated LDH alongside decreased haptoglobin strongly suggests a hemolytic anemia.

Increased reticulocyte count can also occur during hemolysis as the bone marrow responds to the decreased red blood cell mass by producing more immature red blood cells. However, this alone does not specify the process as exclusively hemolytic without the supportive evidence of lactate dehydrogenase and haptoglobin results.

Normal bilirubin levels would not be consistent with hemolysis, as bilirubin, particularly unconjugated bilirubin, tends to rise in hemolysis due to increased breakdown of hemoglobin. Low iron saturation is typically associated with iron deficiency