Platform
Company
Complete Blood Count
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Currently under review
Pending specialist review and validation.
Basophil Manual Percent is the portion of your white blood cells that are basophils, determined by a trained technologist who examines a stained blood smear under a microscope. Basophils are immune cells that contain granules with histamine and other mediators involved in allergic responses and inflammation.
A manual differential is used to visually identify and classify white blood cells and to assess cell appearance. It is often performed when an automated analyzer flags an abnormality or when a closer look at the blood film is needed for quality confirmation.
This test helps your clinician understand whether basophils are proportionately higher or lower than expected, which can occur with allergic conditions, certain chronic inflammatory states, recovery after some infections, and some bone marrow disorders. A low proportion is common with stress and steroid treatment and is usually not concerning by itself.
Doctors order this as part of a complete blood count with differential, to investigate symptoms such as itching, flushing, or persistent inflammation, to verify unexpected automated results, or to monitor known blood or immune conditions. Your result is interpreted alongside symptoms, examination findings, and other blood counts.
A higher basophil percentage can be seen with allergic activity, some chronic inflammatory conditions, and certain bone marrow disorders. A lower percentage can occur with acute illness, stress responses, or medicines like glucocorticoids. Pregnancy and significant fluid shifts can dilute white blood cells and change the proportion seen on a smear.
Your care team will consider both the percentage and the absolute basophil count, together with the rest of the white blood cell differential and your clinical picture. If the result is unexpected, your clinician may repeat the test, review slide quality, look for analyzer flags, and check for medication effects. Further evaluation is guided by your symptoms and history rather than the basophil percentage alone.
Reference intervals vary by laboratory, analyzer, methodology, population, and units. The ranges shown here are for education only. Always interpret your results against the reference interval printed on your own lab report.
Delayed smear preparation, prolonged storage, or improper anticoagulant mixing can distort cells and granules, which can change the observed proportion of basophils on the manual film.
Steroids, epinephrine, and many chemotherapy or targeted agents can lower basophils, while stopping steroids may allow them to rebound. Always share current medicines and supplements.
Active allergic symptoms, asthma flares, or some parasitic infections can be associated with higher basophil proportions due to immune activation.
Acute infections, surgery, or physiological stress can shift white cell distributions, temporarily lowering the basophil percentage on a manual differential.
Pregnancy and significant fluid changes can dilute circulating cells, which may reduce the observed proportion of basophils despite stable overall health.
Manual differentials rely on expert observation. Smear quality, staining, and inter-observer differences can subtly affect classification of rare cells like basophils.
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