What lab results are found in iron deficiency anemia but not in thalassemia?

In iron deficiency anemia, the body lacks sufficient iron to produce hemoglobin, leading to lower levels of serum iron and an increased total iron binding capacity (TIBC). This is because, in response to low iron availability, the liver produces more transferrin, the protein responsible for transporting iron, in an attempt to capture any available iron.

In contrast, thalassemia is a genetic disorder resulting in disrupted hemoglobin synthesis; it is not due to a deficiency in iron but rather an issue with hemoglobin production. In thalassemia, patients often show normal or increased serum iron levels and a low TIBC. This is due to the body having effective iron stores, despite the anemia being due to impaired hemoglobin formation rather than a lack of iron.

Thus, in iron deficiency anemia, low serum iron levels coupled with high total iron binding capacity are characteristic findings, making the identification of low serum iron and high TIBC significant. This difference in lab results is critical in distinguishing between iron deficiency anemia and thalassemia, as it guides appropriate diagnosis and management.