Which laboratory finding is suggestive of hemolytic anemia?

Elevated lactate dehydrogenase (LDH) is indicative of hemolytic anemia because LDH is an enzyme found in many tissues, but it is particularly abundant in red blood cells (RBCs). When RBCs undergo hemolysis, whether in the bloodstream or within the reticuloendothelial system, LDH is released into the circulation. Therefore, an increase in LDH levels serves as a marker for hemolysis, suggesting that the body is experiencing an increased breakdown of red blood cells.

In hemolytic anemia, additional laboratory findings typically include elevated levels of indirect bilirubin due to the increased breakdown of hemoglobin from lysed red cells and a decrease in haptoglobin due to its binding with free hemoglobin released during hemolysis. This finding contrasts with the normal or elevated reticulocyte count typically seen in hemolytic anemia as the bone marrow responds to the anemia by producing more reticulocytes.

The context of elevated LDH within this condition reflects the cellular damage occurring and serves as an important diagnostic clue for clinicians assessing a patient with suspected hemolytic anemia.