From the Guidelines
Microcytic hypochromic anemia is primarily caused by iron deficiency and should be treated with oral iron supplements, such as ferrous sulfate 325 mg taken 1-3 times daily between meals with vitamin C to enhance absorption, as recommended by the most recent guidelines 1. The condition is characterized by smaller than normal red blood cells (microcytic) with reduced hemoglobin content (hypochromic). According to the British Society of Gastroenterology guidelines for the management of iron deficiency anaemia in adults 1, iron deficiency is a major cause of microcytic hypochromic anemia. Key points to consider in the diagnosis and treatment of microcytic hypochromic anemia include:
- Laboratory tests, including complete blood count, iron studies (serum iron, ferritin, total iron binding capacity), and sometimes hemoglobin electrophoresis, are necessary for accurate diagnosis 1.
- The condition is diagnosed when hemoglobin levels are below normal (typically <12 g/dL for women, <13 g/dL for men) with mean corpuscular volume (MCV) <80 fL and mean corpuscular hemoglobin (MCH) <27 pg.
- Addressing the underlying cause is essential for effective treatment and preventing recurrence, and treatment should continue for 3-6 months after hemoglobin normalizes to replenish iron stores 1. It is also important to note that other causes of microcytic hypochromic anemia, such as thalassemia, anemia of chronic disease, sideroblastic anemia, or lead poisoning, should be considered and treated accordingly. However, iron deficiency remains the most common cause, and treatment with oral iron supplements is often the first line of therapy 1.
From the Research
Definition and Characteristics of Microcytic Hypochromic Anemia
- Microcytic anemia is defined as the presence of small, often hypochromic, red blood cells in a peripheral blood smear and is usually characterized by a low MCV (less than 83 micron 3) 2
- Microcytic hypochromic anemia is typically indicated by a patient's history, physical examination results, red cell indexes, and peripheral blood smear 3
Causes of Microcytic Hypochromic Anemia
- Iron deficiency is the most common cause of microcytic anemia 2
- Other causes include anemia of chronic disease, thalassemia, and sideroblastic anemia 2
- The absence of iron stores in the bone marrow remains the most definitive test for differentiating iron deficiency from other microcytic states 2
Diagnosis of Microcytic Hypochromic Anemia
- Measurement of serum ferritin, iron concentration, transferrin saturation, and iron-binding capacity can help diagnose iron deficiency anemia 2
- Serum transferrin receptors may also be used to diagnose iron deficiency anemia 2
- The microcytic to hypochromic RBC ratio can be used as a discriminant index in microcytic anemia to distinguish thalassemia and iron deficiency 4
Treatment of Microcytic Hypochromic Anemia
- Iron supplements are effective in treating iron deficiency anemia 2
- Oral iron preparations are usually well-tolerated and inexpensive 2
- Parenteral iron dextran may be used in cases of malabsorption, losses exceeding maximal oral replacement, or true intolerance 2
Note: The study 5 is not relevant to microcytic hypochromic anemia.