Anaemia is characterised by low haemoglobin in the red blood cells. Haemoglobin is a molecule that is responsible for carrying oxygen to all the cells of the human body. When there is a reduction of haemoglobin, there is also an oxygen-deficit in our cells.Symptoms are varied. The usual symptoms are dizziness, paleness, weakness, headache, delayed growth, learning difficulties and lack of appetite.
There are several reasons for acquiring or having anaemia. A specific study of each individual case can lead to a total cure and also to the prevention of other secondary conditions that may result from anaemia.
There are various types of anaemia
Iron deficiency anaemia (the most common). This is usually caused by a decreased consumption of iron-rich food, or chronic blood loss which is often invisible.
Due to a deficiency in Vitamin B12 or/and Folic Acid. Besides the typical symptoms of anaemia, there may be other, often severe, neurological disorders.
Haemolytic anaemia. This type of anaemia is caused by a destruction of the red blood cells due to antibodies or due to medication.
Aplastic anaemia. Anaemia caused by a decrease in the production of blood cells by the bone marrow. This can be very serious and lead to death if not correctly treated.
Anaemia due to hereditary causes. Inherited anaemia can be more or less severe, according to what type was genetically inherited. Parts of this group are sickle cell disorder, thalassemia and Fanconi anaemia.
Regardless of the type of anaemia, the patient must see a specialist and a diagnosis must be reached. The patient must undergo treatment for the specific anaemia, thus avoiding irreversible brain complications, cardiovascular problems and cerebral vascular accidents (stroke).
The first step in the diagnosis of anaemia is to see a specialist for a physical examination and for a complete medical history. Once haemorrhages or diseases that might cause secondary anaemia are discarded, the investigation should start by considering the patient’s sex, age, ethnic group and its presentation (acute or chronic, its evolution and the probability of a background disease).
To confirm the diagnosis of anaemia, it is necessary to prove that there is a decrease in the concentration of haemoglobin in the blood. It is necessary to undergo a blood test known as a complete blood count (CBC), to determine the concentration of haemoglobin as well as other criteria to indicate size and morphology of the red blood cells. Furthermore, CBC will also inform the specialist of possible alterations in other blood cells such as in the white blood cells and platelets.
A peripheral blood smear should be carried out, where the blood is examined under a microscope. This test can reveal important information as to the cause of the anaemia.
Depending on the suspected diagnosis, many other tests might be necessary, such as to check the iron and ferritin levels (iron deposits in the body), vitamin B12 and folic acid levels, the percentage of reticulocytes (erythrocyte precursor cells), other antibodies, etc.
In cases where the cause of the anaemia is in the bone marrow, a biopsy is in most cases necessary. This consists in the removal of a small portion of bone and bone marrow for analysis.
A myelogram is then carried out from bone marrow removed from the sternum (breastbone) and also from a small fragment of bone of the iliac bone. To carry out these tests, the bone is perforated with a thicker needle and a bone cylinder is removed, permitting a further study of the bone marrow.
For the myelogram test, the aspirated bone marrow smear, is placed on glass slides which are prepared with various dyes and examined under a microscope. A cell count of 700 to 800 cells is made and a percentage calculated which is then compared to a normal cell count. The morphology of each of the cells is also examined where important information is obtained, in order to reach a diagnosis and subsequent treatment of the anaemia.
Both tests are performed under local anaesthesia and the patient does not need any precious care before or after the examination.
It is always important to remember that prevention is better than cure.
By Dr Roger Oliveira
Dr Roger Oliveira is a haematologist at the Hospital Particular do Algarve.