Diagnosis

Sickle cell anaemia is identified via a simple blood test and microscopy.

In adults a sample of blood is taken from a vein in the arm whereas in children the sample is taken from the finger or heel. This sample is then sent to a laboratory where it is screened for haemoglobin S.

Reference of above image: with permission from Microsoft

If the test is negative there is no sickle cell gene present however, if it is positive further tests will be done to determine whether one gene or two sickle cell genes have been inherited. The probabillity of aquiring defective haemoglobin S is greater when two genes are present.

Additional tests include:

• Examination of the sample under a microscope.
• Haemoglobin electrophoresis test to determine the number of sickle cells.
• Anaemia test to check for the blood count.
• Prenatal tests can also be undertaken whereby a sample of fluid in the placenta (amniotic fluid) is taken rather than blood.