Anaemia: Approach To Diagnosis (Part 2)

Anaemia is defined as a condition in which the number of red cells or their oxygen-carrying capacity is insufficient to meet physiological needs. It is the most common disorder globally and one of the conditions that general practitioners most frequently encounter. In the World Health Organization global database, anaemia is estimated to affect 1.6 billion people. Anaemia may result from (i) decreased bone marrow output; or (ii) peripheral loss, destruction or sequestration of red cells. As anaemia manifests in a whole range of conditions, it is important to embrace a structured diagnostic approach. The recommended approach incorporates clinical and pathophysiological considerations, red cell characteristics, and bone marrow activity. Causes of anaemia related to decreased bone marrow output have been discussed in the previous issue of SAMJ, in the first part of this two-part series. The focus of the current article is on peripheral causes of anaemia.