Home Biomarkers Abs. Basophil Count

Abs. Basophil Count

CBC Biomarker

Sample Needed

Collection Type: Blood

Body System

Related System: CBC

Overview

Absolute basophil count measures the number of basophils a rare type of white blood cell in a given volume of blood. Basophils play roles in allergic and inflammatory responses by releasing histamine, heparin and other mediators, and participate in immune surveillance. The test reports an absolute number (not just a percentage) to detect true increases or decreases. Abnormal counts can suggest allergic reactions, parasitic infection, chronic inflammatory states, endocrine conditions (e.g., hypothyroidism), or myeloproliferative disorders (e.g., chronic myeloid leukemia). Indications include unexplained persistent allergies, hives, recurrent infections, unexplained fatigue, splenomegaly or abnormal CBC. Counts vary little by sex, are generally low in infants and children compared with adults, and may shift slightly with age, pregnancy, acute stress or medication use.

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Test Preparation

No special preparation is required

Why Do I Need This Test

Profile: Included in a complete blood count (CBC) with differential.
Symptoms prompting test: ongoing or severe allergic symptoms, unexplained chronic inflammation, recurrent infections, unexplained bruising, fatigue, or signs of a blood disorder (fever, weight loss, enlarged spleen).
Diagnostic/monitoring uses: detects reactive basophilia or basopenia and helps monitor myeloproliferative diseases, allergic/inflammatory conditions, or response to therapy.
Reasons for abnormal levels: allergic inflammation, parasitic infection, chronic inflammatory or endocrine disease (high); acute infection, corticosteroid therapy, stress, hyperthyroidism (low).
Biological meaning: high = increased basophil-mediated inflammatory activity or clonal proliferation; low = suppressed basophil production or redistribution.
Lifestyle/factors: recent corticosteroids, severe stress/illness, smoking or allergen exposure can affect counts.
Family history: relatives with myeloproliferative disorders or inherited hematologic conditions warrants testing.

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Understanding Test Results

Values within 0.0–0.2 x10^9/L are considered normal.
Low values (commonly <0.02 x10^9/L or <20 cells/µL) are often seen in acute infections, after corticosteroid use, with physiologic stress or in hyperthyroidism; isolated mild decreases are usually not clinically urgent.
Mild elevation (0.2–0.5 x10^9/L; 200–500/µL) often reflects reactive causes allergic disease, parasitic infection or chronic inflammation.
Moderate elevation (0.5–1.0 x10^9/L; 500–1000/µL) raises concern for more sustained inflammatory or hematologic processes.
Marked basophilia (>1.0 x10^9/L or >1000/µL) strongly suggests a myeloproliferative neoplasm (for example chronic myeloid leukemia) or other serious marrow disorder and requires prompt hematology evaluation and further testing (repeat CBC, bone marrow studies, molecular/cytogenetic tests).
Always interpret counts alongside symptoms, other CBC indices and clinical history; isolated minor fluctuations often warrant repeat testing rather than immediate invasive workup.

Normal Range

0.0-0.2 x10^9/L OR 0-200 cells/µL

FAQs

Q: What is a low basophil count?

A: Low basophil count (basopenia) means basophils are below the lab reference (typically <0.01–0.1 x10^9/L or under ~1% of white cells). It’s often incidental and not specific, occurring with acute infections, stress, hyperthyroidism, corticosteroid use, pregnancy or after allergic reactions. Persistent or unexplained basopenia should be reviewed with other blood tests and clinical assessment.

Q: What does abs basophils mean?

A: “Abs basophils” means the absolute basophil count the actual number of basophils (a white blood cell involved in allergy and inflammation) per volume of blood (cells/µL or ×10^9/L). Normal values are very low (often near 0 up to ~0.2×10^9/L or ~0–200 cells/µL). High counts (basophilia) suggest allergies, chronic inflammation or myeloproliferative disorders; low counts may occur with acute infection, stress, or steroid use.

Q: What happens if basophil count is high?

A: A high basophil count (basophilia) suggests allergic or inflammatory reactions, infections, thyroid or autoimmune disease, or blood cancers (myeloproliferative neoplasms). It can cause itching, hives, swelling, or reflect systemic signs (fatigue, splenomegaly) depending on the cause. Doctors follow up with repeat blood tests, smear, allergy testing or bone marrow studies and treat the underlying condition.

Q: Should I worry about low basophils?

A: Low basophils (basopenia) are usually not concerning on their own. They can occur with stress, acute infections, corticosteroid use, hyperthyroidism, alcohol, or pregnancy and often normalize. Significance depends on symptoms and other CBC results. If counts stay low, you have unexplained symptoms, or other blood abnormalities, consult your clinician for evaluation and possible further testing.

Q: What if the absolute basophil count is 0?

A: An absolute basophil count of zero is commonly not urgent by itself basophils are normally very low. Transient absence can occur with acute infection, stress, corticosteroid use, or lab variability. Persistent absence or accompanying abnormal blood counts may suggest bone marrow suppression or hematologic disease and warrants a repeat CBC and clinical review. Discuss findings with your clinician.

Q: What cancers cause high basophils?

A: Elevated basophils are most commonly seen in myeloproliferative neoplasms, especially chronic myeloid leukaemia (CML). Other blood cancers that can cause basophilia include polycythaemia vera, essential thrombocythaemia, primary myelofibrosis and some leukemias or myelodysplastic/myeloproliferative overlap syndromes. Rarely, basophilia occurs as a paraneoplastic response to metastatic solid tumours. Further evaluation by a hematologist is advised.