Patients with chronic kidney disease (CKD) may develop anaemia due to a variety of factors, the most significant of which is reduced erythropoietin levels. This is usually a normochromic normocytic anaemia and becomes apparent when the GFR is less than 35 ml/min (other causes of anaemia should be considered if the GFR is > 60 ml/min). Anaemia in CKD predisposes to the development of left ventricular hypertrophy - associated with a three fold increase in mortality in renal patients

Causes of anaemia in renal failure

• reduced erythropoietin levels - the most significant factor
• reduced erythropoiesis due to toxic effects of uraemia on bone marrow
• reduced absorption of iron
• anorexia/nausea due to uraemia
• reduced red cell survival (especially in haemodialysis)
• blood loss due to capillary fragility and poor platelet function
• stress ulceration leading to chronic blood loss

Management

• the 2011 NICE guidelines suggest a target haemoglobin of 10 - 12 g/dl
• determination and optimisation of iron status should be carried out prior to the administration of erythropoiesis-stimulating agents (ESA). Many patients, especially those on haemodialysis, will require IV iron
• ESAs such as erythropoietin and darbepoetin should be used in those 'who are likely to benefit in terms of quality of life and physical function'