Differential Diagnosis for Elevated TIBC, Low Iron Saturation, Normal Ferritin, and Serum Iron

• Single Most Likely Diagnosis
  • Iron deficiency anemia (early stages): This condition is characterized by an increase in Total Iron Binding Capacity (TIBC) and a decrease in iron saturation, which are indicative of the body's attempt to capture more iron from the diet. Normal ferritin levels might suggest that the iron deficiency is in its early stages, as ferritin reflects stored iron and decreases later in the course of the disease.
• Other Likely Diagnoses
  • Anemia of chronic disease: Although ferritin is normal, some chronic diseases can lead to a dissociation between serum iron and ferritin levels. The low iron saturation and elevated TIBC could be seen in the context of chronic inflammation affecting iron metabolism.
  • Pregnancy: Pregnancy can lead to a dilutional anemia and changes in iron metabolism, including increased TIBC and decreased iron saturation, due to increased demand for iron.
• Do Not Miss Diagnoses
  • Thalassemia major or other hemoglobinopathies: These conditions can present with complex iron studies due to chronic hemolysis and transfusion therapy, potentially leading to elevated TIBC and altered iron saturation. Missing these diagnoses could lead to inappropriate management and significant morbidity.
  • Chronic liver disease: Liver disease can affect iron metabolism, leading to abnormal iron studies. Although less common, it's crucial not to miss this diagnosis due to its potential for severe outcomes if left untreated.
• Rare Diagnoses
  • Atransferrinemia: A rare genetic disorder characterized by the absence or very low levels of transferrin, leading to abnormal iron transport and potentially elevated TIBC due to the body's attempt to compensate for the lack of transferrin.
  • Aceruloplasminemia: Another rare genetic disorder affecting iron metabolism, characterized by the absence of ceruloplasmin, which can lead to abnormal iron accumulation and potentially altered iron studies, including elevated TIBC.