From the Guidelines
A reticulocyte count checks for the production of new red blood cells by the bone marrow, helping to evaluate bone marrow function and diagnose or monitor conditions like anemia. Reticulocytes are immature red blood cells that still contain remnants of RNA, which appear as a blue network (reticulum) when stained with special dyes. This test is crucial in distinguishing between different types of anemia, such as those caused by decreased production or increased destruction of red blood cells 1.
Interpretation of Reticulocyte Count
The reticulocyte count is interpreted alongside other blood tests like hemoglobin and hematocrit to provide valuable information about the underlying cause of anemia. A normal reticulocyte count is typically 0.5-2.5% of total red blood cells or 25,000-75,000 cells/microliter. Elevated counts suggest the bone marrow is responding appropriately to blood loss or hemolysis by increasing red blood cell production, while low counts indicate the bone marrow is not producing enough new red blood cells, which may occur in conditions like iron deficiency anemia, bone marrow failure, or certain nutritional deficiencies 1.
Clinical Applications
The reticulocyte count is particularly useful in clinical settings to diagnose and manage anemia in various conditions, including inflammatory bowel diseases, where iron deficiency and anemia of chronic disease often coexist 1. It helps in distinguishing between iron deficiency anemia and anemia of chronic disease, guiding the choice of appropriate treatment.
Key Points
- Reticulocyte count is a measure of bone marrow function and red blood cell production.
- Helps diagnose and monitor conditions like anemia.
- Interpreted alongside other blood tests like hemoglobin and hematocrit.
- Elevated counts suggest increased red blood cell production, while low counts indicate decreased production.
- Crucial in managing anemia in conditions like inflammatory bowel diseases 1.
From the Research
Reticulocyte Count
A reticulocyte (retic) count checks for the number of reticulocytes in the blood, which are immature red blood cells produced by the bone marrow. This test is used to evaluate the status of erythropoiesis, or the production of red blood cells, in the body.
What the Test Measures
The reticulocyte count measures the percentage of reticulocytes in the blood, which can indicate:
- The level of erythropoietic activity in the bone marrow
- The presence of anemia or other blood disorders
- The effectiveness of treatment for anemia or other blood disorders
Parameters Measured
In addition to the reticulocyte count, other parameters that may be measured include:
- Reticulocyte maturity index (RMI)
- High fluorescence reticulocytes (HFR)
- Immature reticulocyte fraction (IRF)
- Mean reticulocyte volume (MCVr)
- Reticulocyte hemoglobin content (CHr)
- Reticulocyte hemoglobin concentration (CHCMr)
Clinical Utility
The reticulocyte count and related parameters can be used to:
- Diagnose iron deficiency anemia and other types of anemia 2
- Monitor the response to iron therapy and other treatments for anemia 2, 3
- Evaluate the effectiveness of erythropoiesis-stimulating agents, such as recombinant human erythropoietin (r-HuEPO) 4
- Differentiate between different types of anemia, such as iron deficiency anemia and beta-thalassemia minor 5
Interpretation of Results
The results of a reticulocyte count can be interpreted in conjunction with other laboratory tests and clinical findings to diagnose and manage various blood disorders. For example: