Anaemia
Also known as: anemia, iron deficiency anaemia, low haemoglobin
A haemoglobin concentration below normal (roughly under 130 g/L in men and 120 g/L in women), reducing the blood's capacity to carry oxygen.
Overview
Anaemia is a sign, not a diagnosis. Iron deficiency from blood loss or poor intake is the commonest cause worldwide; others include vitamin B12 and folate deficiency, chronic disease, kidney failure, inherited haemoglobin disorders and bone marrow failure. Finding the cause matters because in adults it can be bleeding from a bowel cancer.
Causes
- Iron deficiency: heavy periods, gut bleeding, poor diet, malabsorption, pregnancy
- Vitamin B12 or folate deficiency
- Chronic inflammation or kidney disease
- Thalassaemia and sickle cell disease
- Haemolysis
- Bone marrow disease
Risk factors
- Menstruation and pregnancy
- Vegetarian or restricted diets
- Age over 65
- Chronic disease
- Regular NSAID or aspirin use
Symptoms
What a clinician may find
- Pale conjunctivae and palms
- Fast pulse, flow murmur
- Spoon nails, sore tongue in iron deficiency
- Jaundice in haemolysis
- Numb feet and unsteadiness in B12 deficiency
Complications
- Heart failure in severe anaemia
- Poor pregnancy outcomes
- Delayed development in children
- Missed underlying cancer
Diagnosis
Full blood count with red cell size (MCV) points to the type; ferritin, B12, folate, reticulocytes and a blood film narrow it down; coeliac tests and endoscopy or colonoscopy find gut causes of iron deficiency in men and older women.
Treatment
Treat the cause; oral iron for three months after correction (or intravenous iron if not tolerated), B12 injections or folate, erythropoietin in kidney disease, transfusion only for severe or symptomatic anaemia.
Prevention
Iron-rich diet with vitamin C, treating heavy periods, iron supplements in pregnancy where advised, avoiding unnecessary NSAIDs.
When to seek care
Urgent care for breathlessness at rest, chest pain, fainting, or black or bloody stools; routine review for persistent tiredness and pallor.