Blood test
Sickle Cell Test
A sickle cell test checks for sickle cell trait or disease, an inherited condition affecting the shape and function of red blood cells.
Quick answer
Sickle Cell Test: what it is and what the results mean
A sickle cell test looks for abnormal haemoglobin (haemoglobin S) that causes red blood cells to become sickle-shaped. It may be a screening (solubility) test, confirmed by haemoglobin electrophoresis.
- Why it is done: It is used to diagnose sickle cell disease and identify carriers (sickle cell trait), as part of newborn screening, before surgery and anaesthesia, in pregnancy, and for family and pre-conception testing.
- Understanding results: Results show whether you have normal haemoglobin, sickle cell trait (a carrier) or sickle cell disease.
What it is
A sickle cell test looks for abnormal haemoglobin (haemoglobin S) that causes red blood cells to become sickle-shaped. It may be a screening (solubility) test, confirmed by haemoglobin electrophoresis.
Why it is done
It is used to diagnose sickle cell disease and identify carriers (sickle cell trait), as part of newborn screening, before surgery and anaesthesia, in pregnancy, and for family and pre-conception testing.
What to expect
It is an ordinary blood test from a vein in the arm (or a heel-prick in newborns), needing no special preparation. Positive or abnormal screening results are confirmed with further tests.
Understanding the results
Results show whether you have normal haemoglobin, sickle cell trait (a carrier) or sickle cell disease. Carriers are usually healthy but can pass the gene on, which matters for family planning; disease needs specialist care.
Good to know
Risks and limitations
It is a safe blood test. Screening tests are confirmed by more detailed analysis, and interpreting carrier states is important for genetic counselling.
Education and reference only. This explains the test in general terms and is not medical advice. Always follow the specific instructions from the team arranging your test, and discuss your results with your clinician.
Answers
Sickle Cell Test: frequently asked questions
What is the difference between sickle cell trait and disease?
People with sickle cell trait carry one copy of the gene, are usually healthy, but can pass it on. Sickle cell disease means two affected genes and causes symptoms needing lifelong specialist care.
Why is sickle cell checked before surgery?
Certain conditions during anaesthesia and surgery, such as low oxygen, can trigger problems in people with sickle cell disease, so knowing the status allows precautions to be taken.
Related tests
Other blood test investigations
Sources
Where this is drawn from
- NHS — Tests and treatments
- NICE — diagnostic guidance
- British Society for Haematology / relevant professional body
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