What are the types of anemia?

From the Guidelines

Anemia is classified into several types, including microcytic, normocytic, and macrocytic anemia, which can be further divided based on the presence of normal or elevated reticulocytes, and the underlying causes can be identified through a combination of complete blood count, reticulocyte count, and specific nutrient levels, as outlined in the European consensus on the diagnosis and management of iron deficiency and anaemia in inflammatory bowel diseases 1. The main types of anemia include:

• Microcytic anemia, which can be caused by iron deficiency, anemia of chronic disease, thalassemia, or sideroblastic anemia
• Normocytic anemia, which can be caused by hemorrhage, hemolysis, bone marrow failure, anemia of chronic inflammation, or renal insufficiency
• Macrocytic anemia, which can be caused by vitamin B12 or folate deficiency, alcoholism, or certain medications Other types of anemia include:
• Hemolytic anemia, resulting from premature destruction of red blood cells
• Aplastic anemia, where bone marrow fails to produce enough blood cells
• Sickle cell anemia, an inherited condition causing abnormally shaped red blood cells
• Thalassemia, inherited disorders affecting hemoglobin production
• Anemia of chronic disease, associated with long-term conditions like cancer or kidney disease
• Pernicious anemia, an autoimmune condition affecting B12 absorption The diagnosis and management of anemia should be based on the underlying cause and characteristics of red blood cells, as well as the presence of inflammation or other underlying conditions, as discussed in the European consensus on the diagnosis and management of iron deficiency and anaemia in inflammatory bowel diseases 1 and the approaches to evaluation of anemia 1. Key laboratory tests for diagnosing anemia include:
• Complete blood count (CBC) with mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH)
• Reticulocyte count
• Serum ferritin and transferrin saturation
• Vitamin B12 and folate levels
• Haptoglobin, lactate dehydrogenase, and bilirubin levels to evaluate for hemolysis Proper diagnosis and treatment of anemia can improve morbidity, mortality, and quality of life, as emphasized in the study on cancer- and chemotherapy-induced anemia 1.

From the Research

Types of Anemia

• Anemia can be classified based on the measured red cell size (MCV) into:
  • Microcytic anemia 2, 3, 4, 5
  • Normocytic anemia 2, 3, 4
  • Macrocytic anemia 2, 3, 6, 4
• Anemia can also be classified based on the cause, including:
  • Deficient erythropoiesis (e.g. aplastic anemia, myelodysplastic syndromes, iron deficiency anemia, anemia of chronic disease) 2
  • Excessive RBC destruction (e.g. hereditary spherocytosis, inherited enzyme deficiency, hemoglobinopathies, autoimmune hemolytic anemia) 2, 3
  • Blood loss 2
• Specific types of anemia include:
  • Iron deficiency anemia 2, 3, 4, 5
  • Anemia of chronic disease 2, 3, 4
  • Thalassemia 2, 3, 5
  • Megaloblastic anemia 2, 6
  • Myelodysplastic syndromes (MDS) 2, 6
  • Hemoglobinopathies (e.g. sickle cell disease, hemoglobinopathy E) 2, 3, 5
  • Autoimmune hemolytic anemia (AIHA) 2, 3
  • Paroxysmal nocturnal hemoglobinuria (PNH) 2, 3