Anaemia

Haematology

Overview The World Health Organization defines anaemia as a haemoglobin (Hb) concentration below 13 g/dl (130 g/L) in men over 15 years of age, below 12 g/dl (120g/L) in non-pregnant women over 15 years of age, and below 11 g/dl (110g/L) in pregnant women. There are many causes of anaemia. It is important to take a comprehensive history, examination and inspect FBC and blood films

Remember Anaemia men: 130g/L and in women: 120g/L

Physiology of RBCs

Watch: Haematology - Red Blood Cells

Watch: Haematology - RBC life cycle

Approach

History
- Symptoms of Anaemia (fatigue, shortness of breath)
- Sleeping - Obstructive sleep Apnoea
- Pancytopaenia (easy bruising, bleeding, infections)
- Family History of haemolytic disease
- Menstrual history: menorrhagia, menometrorrhagia
- Connective Tissue disorder
- Neurological symptoms
- Medication history
- Ethnic background
- Medical condition
- Surgical history - heart valve surgery associated with haemolysis
Examination
- Jaundice
- Pallor
- Splenomegaly
- Hepatomegaly
- Signs of connective tissue disease

Investigations If anaemia is suspected begin with:

Full blood examination
Iron studies
Serum vitamin B12/folate
Peripheral Blood film
Reticulocyte count

Reticulocytes are immature erythrocytes and are markers of erythrocyte production. The reticulocyte count should always be interpreted in the context of the Hb. Should normally increase when there is a decrease in RBC

The first step in diagnosing the cause of anaemia is to find out the mean cell volume (MCV). The initial classification is based on the MCV:
- Microcytic Anaemia
- Normocytic Anaemia
- Macrocytic Anaemia
Any further investigations will be determined by the blood film appearance and clinical suspicion

DIFFERENT TYPES OF ANAEMIA BASED ON MCV
Microcytic Anaemia	Normocytic Anaemia	Macrocytic Anaemia
Iron-deficiency	Anaemia of chronic disease (MCV may be reduced)	Vitamin B12 deficiency
Thalasaemia	Haemolytic anaemia (hemolysis)	Alcohol excess
Sideroblastic anaemia	Acute blood loss	Reticulocytosis
	Bone marrow failure/CKD	Myelodysplastic syndrome
	Hypothyroidism	Myeloproliferative disorders
	Pregnancy	Hypothyroidism
		Folate deficiency