Health News, Information and Advice from a British Doctor

Low blood count (usually meaning ANAEMIA)

The causes of anaemia are plentiful and complex but symptoms tend to the same whatever the underlying cause is. These are as follows;

  • tiredness
  • lethargy and no energy
  • shortness of breath particularly on exercising
  • no ‘get up and go’
  • sometimes loss of appetite and weight loss
  • palor (particularly the mucus membranes such as the conjunctiva, but also the nails may appear very pale too)

Iron deficiency anaemia This is the commonest cause of anaemia and is due to lack of iron which is essential for making red blood cells. Iron deficiency anaemia occurs when there isn’t enough iron getting into the blood stream from the gut (this is usually because not enough is being eaten) or may arise as a result of blood loss (usually from the gut and may be unnoticeable, or in menstruating women) Red blood cells are circulating cells that contain no nucleus but are packed with haemoglobin and are responsible for transporting oxygen to all of our tissues from the lungs. It is the red blood cells that give us our pink colour and makes us look healthy! Iron is an essential component of haemoglobin and without it not enough haemoglobin is manufactured and the red cells look pale and small under the microscope (hypochromic and microcytic). Red meat, green vegetables and dairy products are rich sources of iron, so diets which are lacking in these can cause anaemia. The iron is modified (reduced) by gastric acid when it hits the stomach, which makes it more easily absorbed into the blood stream, this absorption occurs in the first bit of the small intestine (duodenum and jejunum). Phytates and tannates (present in tea and coffee) may slow down this absorption and vitamin C speeds it up, so citrus fruits are good for preventing iron deficiency. Any pathology affecting the small intestine (such as coeliac disease and Crohn’s disease) may interfere with this absorption too. Once the iron hits the blood stream, it binds to a special protein called transferrin and is transported to the bone marrow to make red blood cells. Extra iron is stored in very large molecules in the liver, called ferritin and your doctor may well ask for this blood test as it is a good indicator of iron stores.
Blood loss Menstruating women have lower normal blood counts than men because of the cyclical blood loss. However blood can also be lost in other ways and into the gut is the most common, although the urinary tract may be another source of blood loss. This blood loss is usually unnoticed (microscopic) but can cause significant anaemia and may be associated with serious pathology. Loss of blood into the gut forms the basis of the NHS screening programme (FOBT) for bowel cancer, when healthy patients have to provide a specimen of faeces to be tested for microscopic amounts of blood. This is available to the older population (usually over 60 – 75) The following are the commonest causes of microscopic blood loss into the gut;

  • Gastric inflammation
  • Peptic ulcer
  • Inflammatory bowel disease such as Crohn’s disease or ulcerative colitis
  • Large bowel polyps
  • Bowel cancer

Written by Dr M J Webberley, Consultant Gastroenterologist, August 2015