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Focus on Anaemia Care in the Elderly



Classification of anaemia

Pathogenic classification

A pathogenic classification of anaemia is shown in Table 32. However, in older patients anaemia may be more simply subdivided as follows:1

Nutrient-deficiency anaemia is due to a lack of iron, and/or folate, and/or vitamin B12. When this results from a dietary deficiency a hypo-regenerative anaemia occurs, characterised by a decrease in the production of erythrocytes. Nutrient-deficiency anaemia also commonly arises due to acute or chronic bleeding, leading to a regenerative anaemia in which the bone marrow is able to respond appropriately to a low erythrocyte mass by increasing production of erythrocytes.2

Anaemia of chronic inflammation occurs in patients with chronic inflammatory diseases such as cancer, infectious disease, diabetes and autoimmune disease and is defined by low serum iron (< 60 µg/dl) without evidence of iron deficiency.2-4 A hypo-regenerative anaemia develops, apparently due to the deleterious effects of systemic inflammation on erythropoiesis, erythropoietin production, erythrocyte survival, and the recycling of iron.4

Anaemia of chronic kidney disease directly results from an impairment of erythropoietin production, leading to a hypo-regenerative anaemia.1,2

Unexplained anaemia is anaemia that cannot be classified into any of the other categories.1

Hyper-regenerative anaemiaHyporegenerative anaemia
Corpuscular anaemia
Hemolytic anaemia
  • due to membrane defects (e.g. spherocytosis, elliptocytosis)
  • due to mechanical destruction (aortic valve replacement)
Non-corpuscular anaemia
Haemoglobinopathy (e.g. thalassaemia, sickle cell disease)
Enzymopathy (e.g. glucose-6-phosphate or pyruvate kinase deficiency)
Acquired autoimmune haemolysis
Toxic-metabolic drugs
Infectious (e.g. malaria, babesia)
Hypersplenism (e.g. liver cirrhosis)
Acute or chronic bleeding
Paroxysmal nocturnal haemoglobinuria
Chronic bleeding
Bone marrow failure caused by stem cell pathology
Quantitative disorder
  • Selective: erythroblastopenia (pure red cell aplasia)
  • Global: aplastic anaemia
Qualitative disorder (dysmyelopoiesis)
  • Inherited: hereditary dyserythropoiesis
  • Acquired: myelodysplasia
Bone marrow infiltration
Leukaemia, lymphoma, multiple myeloma
Solid tumors
Erythropoietic factor deficiency
Iron deficiency anaemia
Anaemia of chronic disease
Cobalamin and folate
Hormones: erythropoietin, thyroid hormones, androgens, steroids
Thesaurismosis (Gaucher’s disease)
Inflammatory chronic diseases, infections (Histoplasma, HIV)
Drugs, hypothyroidism, uraemia

Table 3. Aetiopathogenic classification of anaemia. (Adapted from Chulilla et al.)2


  1. Patel KV. Epidemiology of anaemia in older adults. Semin Hematol. 2008;45(4):210-7.
  2. Chulilla JAM, et al. Classification of anaemia for gastroenterologists. World J Gastroenterol. 2009;15(37):4627-37.
  3. Guralnik JM, et al. Prevalence of anaemia in persons 65 years and older in the United States: evidence for a high rate of unexplained anaemia. Blood. 2004;104(8):2263-8.
  4. Ferrucci L, Balducci L. Anaemia of aging: the role of chronic inflammation and cancer. Semin Hematol. 2008;45(4):242-9.

Morphologic classification

In daily clinical practice, mean corpuscular volume (MCV) enables anaemia to be classified as microcytic, normocytic and macrocytic, according to the average erythrocyte size.1

Microcytic anaemia occurs as a result of iron-deficiency anaemia, thalassaemia and anaemia of chronic disease (e.g. rheumatoid arthritis, chronic infection, neoplasia).1

Normocytic anaemia may be caused by combined nutritional deficiency (vitamin B12, folate and iron), renal failure, haemolytic anaemia, gastrointestinal bleeding, and bone marrow disorders.1

Macrocytic anaemia may result from nutritional deficiency (vitamin B12 or folate), drug-induced haemolytic anaemia, gastrointestinal bleeding, and bone marrow disorders.1

Microcytic anaemia. Hypochromic and microcytic red blood cells in a patient with severe iron deficiency anaemia due to gastrointestinal blood loss.
This image was originally published in ASH Image Bank.
Author(s): Stanley Schrier.
Title: Red Blood Cell Diseases (RBC) 2 - 1.
ASH Image Bank 2002 image number: 00001578. © the American Society of Hematology
Normocytic anaemia. Despite a reduction in the total number of red cells, the RBC indices are normal, and the cells have the typical area of central pallor without widespread variation in size and shape.
This image was originally published in ASH Image Bank.
Author(s): Peter Maslak.
Title: Normochromic normocytic anaemia - 1
ASH Image Bank 2008 image number: 00003710. © the American Society of Hematology


  1. Chulilla JAM, et al. Classification of anaemia for gastroenterologists. World J Gastroenterol. 2009;15(37):4627-37.

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