From the Guidelines
The reticulocyte count, or Retocrit, is a measure of the number of immature red blood cells in the blood, which provides an indication of the bone marrow's ability to produce new red blood cells. This measurement is crucial in evaluating anemia, as it helps distinguish between different causes of anemia, such as decreased production, increased destruction, or blood loss. According to the study published in the Journal of the National Comprehensive Cancer Network in 2012 1, the reticulocyte count is a key component of the kinetic approach to evaluating anemia, which focuses on the underlying mechanism of anemia.
The reticulocyte count can be used to identify various conditions, such as iron deficiency, vitamin B12 or folate deficiency, aplastic anemia, or bone marrow dysfunction caused by cancer or cancer-related therapy. A low reticulocyte index (RI) indicates decreased red blood cell production, while a high RI suggests normal or increased red blood cell production, which may be seen in cases of blood loss or hemolysis. The study published in the American Journal of Kidney Diseases in 2001 1 also highlights the importance of reticulocyte count in evaluating anemia in patients with chronic kidney disease.
In clinical practice, the reticulocyte count is essential in diagnosing and managing anemia, and it should be interpreted in conjunction with other laboratory tests, such as mean corpuscular volume (MCV), serum iron, and total iron binding capacity (TIBC). By considering the reticulocyte count and other relevant factors, healthcare providers can develop effective treatment plans for patients with anemia, which may include iron supplementation, vitamin B12 or folate replacement, or other interventions to address the underlying cause of anemia.
Key points to consider when interpreting reticulocyte count include:
- A normal reticulocyte index (RI) ranges between 1.0 and 2.0 1
- A low RI indicates decreased red blood cell production, while a high RI suggests normal or increased red blood cell production 1
- The reticulocyte count should be interpreted in conjunction with other laboratory tests, such as MCV, serum iron, and TIBC 1
- Iron deficiency is a common cause of anemia, and the reticulocyte count can help identify this condition 1
From the Research
Definition of Reticulocyte Count
- The reticulocyte count, also known as Retocrit, is a measure of the number of reticulocytes in the blood [(2,3,4,5,6)].
- Reticulocytes are the youngest erythrocytes released from the bone marrow into the blood and they circulate for 1-2 days before becoming mature erythrocytes 3.
Importance of Reticulocyte Count
- The reticulocyte count is a good marker of erythropoietic activity of the bone marrow 4.
- It can be used to diagnose and monitor iron deficiency anemia, as well as other types of anemia [(2,3,5,6)].
- Reticulocyte parameters, such as mean corpuscular volume of reticulocyte (MCVr) and mean content hemoglobin of reticulocyte (CHr), can be useful in differential diagnosis of iron deficiency anemia, vitamin B12 deficiency anemia, and beta-thalassemia minor [(3,5,6)].
Measurement of Reticulocyte Count
- Reticulocyte count can be measured using automated blood cell analyzers, such as the Sysmex XE-2100 [(4,5)].
- The measurement of reticulocyte count and parameters can be a useful implement in the diagnosis of iron deficiency anemia and other types of anemia 6.
- However, there are limitations and potential errors in the measurement of reticulocyte count, such as pseudoreticulocytosis in leukocytosis samples 4.