What is the next step in managing a patient with an elevated Red Cell Distribution Width (RDW) and symptoms of anemia?

From the Guidelines

The next step in managing a patient with elevated RDW and anemia symptoms should be a comprehensive diagnostic workup to determine the underlying cause, including a complete blood count with differential, peripheral blood smear, reticulocyte count, iron studies, vitamin B12 and folate levels, and hemoglobin electrophoresis, as recommended by the most recent guidelines 1. This approach is crucial because an elevated RDW indicates increased variation in red blood cell size (anisocytosis) and can occur in various conditions, including iron deficiency anemia, vitamin B12 or folate deficiency, hemoglobinopathies, myelodysplastic syndromes, or chronic inflammation.

• The diagnostic workup should include:
  • Complete blood count with differential
  • Peripheral blood smear
  • Reticulocyte count
  • Iron studies (serum iron, ferritin, total iron binding capacity)
  • Vitamin B12 and folate levels
  • Hemoglobin electrophoresis
• Depending on clinical suspicion, additional tests may include:
  • Thyroid function tests
  • Liver function tests
  • Kidney function tests
  • Inflammatory markers
• Treatment should target the specific underlying cause rather than the RDW itself, as indicated by the European Consensus on the diagnosis and management of iron deficiency and anaemia in inflammatory bowel diseases 1.
• For example, iron deficiency would require iron supplementation, while B12 deficiency might require cyanocobalamin injections, and the British Society of Gastroenterology guidelines for the management of iron deficiency anaemia in adults provide further guidance on this approach 1.
• During the diagnostic process, severe symptomatic anemia (hemoglobin <7 g/dL with symptoms) may require blood transfusion for immediate stabilization, as suggested by the KDIGO guideline on anemia 1.

From the Research

Next Steps in Managing Elevated RDW and Anemia Symptoms

• The patient's elevated Red Cell Distribution Width (RDW) and symptoms of anemia require further investigation to determine the underlying cause of the anemia, as stated in 2.
• Iron deficiency is a common cause of elevated RDW, and studies have shown that RDW can be used as a diagnostic tool for iron deficiency anemia, with a sensitivity of 77.1% and specificity of 90.6% 3.
• The RDW index has been found to be a good indicator of anisocytosis and a good screening index for iron deficiency anemia and thalassemia trait, with elevated RDW values found in anemic patients, particularly those with iron deficiency anemia 4.
• In patients with iron deficiency anemia, the RDW has been shown to be elevated, even in the prelatent and latent stages of iron deficiency, making it a useful tool for early detection 5.
• The severity of iron deficiency in iron deficiency anemia can be reflected by the degree of elevation of RDW, with higher RDW values indicating more severe iron deficiency 6.

Potential Causes and Diagnostic Considerations

• Iron deficiency anemia should be considered as a potential cause of the patient's elevated RDW and anemia symptoms, and further testing, such as iron profile and RBC indices, should be conducted to confirm the diagnosis 3, 5.
• Other potential causes of elevated RDW, such as thalassemia trait or other hemoglobinopathies, should also be considered and ruled out through further testing 4, 6.
• The patient's medical history, physical examination, and laboratory results should be carefully evaluated to determine the underlying cause of the anemia and to guide further management 2.