Basophils
What this test measures
Basophils are the least numerous white blood cells. They release histamine and other chemicals in allergic reactions, and are close relatives of the mast cells found in the tissues. This is the absolute number in a given volume of blood, and it is normally very small.
Why doctors request it
It is printed as part of the full blood count differential rather than requested on its own. Doctors rarely act on it alone; a persistently high count is one of the pointers towards a group of bone marrow conditions.
What commonly pushes it up
- Allergic reactions
- An underactive thyroid
- Some bone marrow conditions, particularly chronic myeloid leukaemia
- Inflammatory bowel disease
- Recovery from an infection
What commonly pushes it down
- Steroid medicines
- An overactive thyroid
- Acute infection and stress
- Pregnancy and ovulation, slightly
Everyday reasons for a value outside the range
- The count is so small that analysers measure it with limited precision, so 0.0 and 0.1 are both usual
- Steroid tablets lower it as an expected effect
About the sample
No fasting needed. Rarely of importance on its own.
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Read my report freeThis is an educational summary of results you uploaded. It is not medical advice, a diagnosis or a treatment plan, and it does not replace the doctor who requested the test. If you are worried, or a result is marked outside range, discuss it with your doctor. Written and reviewed by a UK consultant physician. Reference ranges vary between laboratories.