From the Guidelines
Anemia, or a low red blood cell count, is primarily caused by iron deficiency, vitamin B12 deficiency, or folate deficiency, and its diagnosis and management should be guided by a comprehensive evaluation of the patient's medical history, physical examination, and laboratory tests, including complete blood count, reticulocyte count, and serum ferritin levels, as recommended by the most recent and highest quality study 1.
Causes of Anemia
The causes of anemia can be classified into three main categories:
- Iron deficiency anemia, which is the most common cause of anemia worldwide, and is often due to inadequate iron intake, increased iron requirements, or chronic blood loss 1.
- Vitamin B12 or folate deficiency anemia, which can be caused by inadequate dietary intake, malabsorption, or increased requirements 1.
- Anemia of chronic disease, which is often seen in patients with chronic inflammatory conditions, such as cancer, chronic kidney disease, or rheumatoid arthritis, and is characterized by a normocytic or microcytic anemia with a low reticulocyte count and elevated serum ferritin levels 1.
Diagnosis and Management
The diagnosis and management of anemia should be guided by a comprehensive evaluation of the patient's medical history, physical examination, and laboratory tests, including:
- Complete blood count (CBC) to determine the severity of anemia and the presence of any underlying conditions, such as thrombocytopenia or leukopenia.
- Reticulocyte count to assess the bone marrow's response to anemia and to distinguish between hypoproliferative and hyperproliferative anemias.
- Serum ferritin levels to assess iron stores and to diagnose iron deficiency anemia.
- Vitamin B12 and folate levels to diagnose vitamin B12 or folate deficiency anemia.
Treatment
The treatment of anemia depends on the underlying cause and may include:
- Iron supplements, such as ferrous sulfate, to treat iron deficiency anemia.
- Vitamin B12 supplements, such as cyanocobalamin, to treat vitamin B12 deficiency anemia.
- Folic acid supplements to treat folate deficiency anemia.
- Blood transfusions in severe cases of anemia.
- Dietary changes, such as increasing iron-rich foods, vitamin B12 sources, and folate-rich foods, to help manage anemia.
- Addressing underlying conditions, such as chronic diseases, bleeding disorders, or bone marrow problems, to prevent and manage anemia.
From the Research
Causes of Anemia
The causes of anemia, a condition characterized by a low red blood cell count, can be diverse and multifaceted. Some of the key causes include:
- Iron deficiency, which is the most common cause of anemia 2, 3, 4
- Nutritional deficiencies, such as a lack of vitamin B12 and folate 2, 5, 3
- Blood loss, which can be caused by various factors such as gastrointestinal bleeding, menstruation, or surgery 2, 6, 4
- Systemic diseases, such as renal disease, malignancy, rheumatologic disorders, and endocrine disorders 2, 6
- Inherited disorders, such as myelodysplastic syndromes and myeloma 2, 6
- Alcohol use, which can lead to macrocytic anemia 2
- Thyroid disease, which can also cause macrocytic anemia 2
- Certain medications, such as hydroxyurea and antiretroviral drugs, which can lead to macrocytic anemia 2
Classification of Anemia
Anemia can be classified into different types based on the mean corpuscular volume (MCV), which guides the differential diagnosis and evaluation 2. The main types of anemia include:
- Microcytic anemia, which is characterized by small red blood cells and is often caused by iron deficiency 2, 3
- Normocytic anemia, which is characterized by normal-sized red blood cells and has a broad differential diagnosis, including nutritional deficiencies, blood loss, and systemic diseases 2
- Macrocytic anemia, which is characterized by large red blood cells and is often caused by vitamin B12 and folate deficiency, alcohol use, and certain medications 2, 5