From the Guidelines
Elevated red blood cell count with decreased MCV and MCH is most likely indicative of microcytic hypochromic anemia, which can be caused by iron deficiency, thalassemia, or anemia of chronic disease, with iron deficiency being the most common cause. This condition is characterized by the body's attempt to compensate for the reduced oxygen-carrying capacity of the red blood cells by producing more of them, resulting in an elevated red blood cell count. The decreased MCV and MCH values suggest that the red blood cells are smaller and have less hemoglobin than normal, which is consistent with microcytic hypochromic anemia 1.
According to the European consensus on the diagnosis and management of iron deficiency and anaemia in inflammatory bowel diseases, microcytic anaemia with normal or low reticulocytes is often associated with iron deficiency or anaemia of chronic disease 1. The study published in the Journal of Crohn's and Colitis in 2015 provides a classification of anaemia by MCV and reticulocytes, which can be useful in determining the underlying cause of the anaemia.
The evaluation of microcytic hypochromic anemia should include serum iron studies, ferritin levels, and possibly hemoglobin electrophoresis to determine the exact cause 2. Treatment depends on the underlying condition, but often involves iron supplementation, typically ferrous sulfate 325mg daily, for iron deficiency, while thalassemia management is more supportive. Identifying and addressing the root cause, such as occult bleeding in iron deficiency cases, is essential for effective treatment.
Some possible causes of microcytic hypochromic anemia include:
- Iron deficiency due to inadequate iron intake, chronic blood loss, or poor iron absorption
- Thalassemia, a genetic disorder affecting hemoglobin production
- Anemia of chronic disease, which can be caused by chronic inflammation, cancer, or other underlying conditions
- Other less common causes, such as lead poisoning or hereditary microcytic anemia.
It is essential to note that the treatment and management of microcytic hypochromic anemia should be individualized based on the underlying cause and the patient's specific needs.
From the Research
Elevated Red Blood Cell Count with Decreased MCV and MCH
- Elevated red blood cell count combined with a low mean corpuscular volume (MCV) is generally attributed to thalassemia minor, either alpha or beta, or to polycythemia vera with iron deficiency 3.
- A high RBC count with a low MCV can also be caused by secondary polycythemia with incidental iron deficiency, which can be distinguished from thalassemia minor and polycythemia vera using RBC size distribution curves 3.
- Microcytic anemia, characterized by a low MCV, is often caused by iron deficiency, which can be diagnosed by measuring serum ferritin, iron concentration, transferrin saturation, and iron-binding capacity 4.
- The evaluation of microcytosis, defined as a mean corpuscular volume of less than 80 µm3, should include serum ferritin measurement, and low ferritin levels suggest iron deficiency 5.
- In patients with polycythemia vera, iron deficiency is common, and treatment with ruxolitinib has been shown to improve iron marker levels and patient-reported outcomes, particularly in those with baseline iron deficiency 6.
- Phlebotomy with iron therapy can be used to correct microcytic polycythemia in patients with chronic hypoxia, improving iron stores while maintaining a stable hematocrit level 7.