Renal Anaemia

Definition

Anaemia is defined as a reduction of the number of circulating red blood cells to below a certain threshold level. It is also described as a low haemoglobin concentration or a low volume of packed red cells¹. Low haemoglobin levels lead to insufficient oxygenation of organs. Diagnosis is through blood tests using normal ranges calibrated from large populations.

The main causes of anaemia include¹:

Insufficient production of RBC; often referred to as hypoproliferative anaemia. This includes iron deficiency, chronic kidney disease (CKD), and anaemia caused by inflammation due to chronic disease (such as rheumatoid arthritis or cancer).
Loss of blood; anaemia can result from excessive blood loss whereby the body is unable to correct low blood levels brought about by excessive bleeding, inflammation or malignancy.
RBC destruction; a number of diseases, including genetic disorders can lead to the destruction of RBCs, impaired synthesis or the formation of abnormal haemoglobin. Such diseases include thalassaemia and sickle cell disease.

Renal anaemia refers specifically to anaemia secondary to CKD. Renal anaemia is an almost inevitable feature of CKD because the kidneys play an important role in the production of red blood cells, which transport oxygen in the body. CKD is a progressive condition, which is characterized by permanent kidney damage and is often associated with gradual loss of kidney function over time.

Reference:
1. NAAC (National Anemia Action Council) Anemia monograph. Available at http://anemia.org/professionals/monograph/ [Accessed June 2008].