Definition A lack of the red cells which carry oxgyen in the blood and occurs for many different reasons. In serious bowel diseases it occurs because of a slow, continuous unnoticed loss of blood into the gut over months perhaps years wich results in deficiency of iron. This is required to make new red cells and when anaemia is caused by a lack of iron it is called ‘iron deficiency anaemia’ or IDA.

Prevalence Mild anaemia is common particularly in women before the menopause and in patients who take asprin like pain killers and those on iron deficient diets. However IDA in all men and in women with no obvious cause should be investigated to make sure they do not have bowel cancer.

Symptoms of Anaemia These only occur when the anaemia is very severe which is uncommon even in serious bowel conditions. This means that anaemia is usually detected as the result of routine blood tests rather than because it is low enough to cause symptoms. Symptoms include breathlessness on exercise, lethargy and tiredness.

IDA and bowel cancer This is an important characteristic of nearly 30% of all bowel cancers although very few patients present with the symptoms of anaemia, most also have one of the three key symptoms of bowel cancer. This means that anyone with one of these symptoms should be checked for IDA.

Treatment Iron tablets will usually cure mild IDA very quickly and if there is a clear cause it is reasonable to stop treatment when the blood test becomes normal and watch and wait. However if the IDA recurs then full investigations are required to exclude the possibility of a serious bowel condition.