Haemolytic anaemias

• Thalassaemia
• Sickle cell disorders
• Other hereditary haemolytic anaemias
• Anaemia due to enzyme disorders

Destruction of red blood cells causes anaemia if the degree of cell breakdown exceeds the regenerative ability of the bone marrow. Some haemolytic anaemias are inherited e.g., Hereditary Spherocytosis, where symptoms usually appear in childhood, but are often insufficient to cause the patient discomfort or disability, and with only mild to moderate degrees of anaemia and jaundice.

"Crises" may occur at variable intervals, with severe anaemia and jaundice, and at such times the patient may complain of weakness and breathlessness, which in severe cases may be very marked and associated with rigors, fever, and vomiting, invariably resulting in hospital admission. The mechanism of "crises" is unknown, but may be precipitated by infection.

Between crises, which are short- lived, the patient is relatively well, able to carry out work and able to carry out all activities of daily living. Many patients live a normal life and die of old age while others suffer from severe episodes of haemolytic anaemia or secondary gall bladder inflammation, due to the buildup of pigment stones in the gall bladder. Such episodes may end fatally.

Course of the disease in hereditary spherocytosis

Removal of the spleen (splenectomy) results in striking and usually permanent improvement both in the symptoms and in the anaemia, and is carried out when the anaemia causes persistent impairment of health, when severe haemolytic crises have occurred, when other members of the family have died of the disease, or where there is evidence of gall bladder disease.

Hereditary Haemoglobinopathies (causing abnormal haemoglobin synthesis).

i.e. includes a wide range of blood disorders which in some cases results in the consequent haemolytic anaemia to be so severe, that fatal results occur. In other patients the disease may be so mild as to cause little or no inconvenience. Examples of hereditary haemoglobinopathies include Thalassaemia and Sickle Cell Disease.

There is no specific treatment, and splenectomy is contraindicated. The increase in immigration into the UK over the years of racial groups in whom haemoglobinopathies are common, has resulted in identification of considerable numbers of persons suffering from disease related to haemoglobinopathies. Very occasionally, refractory iron deficiency anaemia in British subjects without known Mediterranean ancestry may be due to Thalassaemia minor.