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URL of this page: https://medlineplus.gov/bloodcounttests.html
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Summary
Your blood contains red blood cells (RBC), white blood cells (WBC), and platelets. Blood count tests measure the number and types of cells in your blood. This helps doctors check on your overall health. The tests can also help to diagnose diseases and conditions such as anemia, infections, clotting problems, blood cancers, and immune system disorders.
Specific types include tests for:
- RBC - the numbers, size, and types of RBC in the blood
- WBC - the numbers and types of WBC in the blood
- Platelets - the numbers and size of the platelets
- Hemoglobin - an iron-rich protein in red blood cells that carries oxygen
- Hematocrit - how much space red blood cells take up in your blood
- Reticulocyte count - how many young red blood cells are in your blood
- Mean corpuscular volume (MCV) - the average size of your red blood cells
The complete blood count (CBC) includes most or all of these. The CBC is one of the most common blood tests.
NIH: National Heart, Lung, and Blood Institute
Related Issues
- High Red Blood Cell Count (Mayo Foundation for Medical Education and Research) Also in Spanish
- Low White Blood Cell Count (Mayo Foundation for Medical Education and Research) Also in Spanish
- Overview of White Blood Cell Disorders (Merck & Co., Inc.) Also in Spanish
- Platelet Disorders: MedlinePlus Health Topic (National Library of Medicine) Also in Spanish
Specifics
- Blood Differential (National Library of Medicine) Also in Spanish
- Blood Smear (National Library of Medicine) Also in Spanish
- Hematocrit Test (National Library of Medicine) Also in Spanish
- Hemoglobin Electrophoresis (National Library of Medicine) Also in Spanish
- Hemoglobin Test (National Library of Medicine) Also in Spanish
- MCV (Mean Corpuscular Volume) (National Library of Medicine) Also in Spanish
- MPV Blood Test (National Library of Medicine) Also in Spanish
- Platelet Tests (National Library of Medicine) Also in Spanish
- RDW Red Cell Distribution Width (National Library of Medicine) Also in Spanish
- Red Blood Cell (RBC) Count (National Library of Medicine) Also in Spanish
- Red Blood Cell (RBC) Indices (National Library of Medicine) Also in Spanish
- Reticulocyte Count (National Library of Medicine) Also in Spanish
- White Blood Count (WBC) (National Library of Medicine) Also in Spanish
Images
- Complete blood count - series (Medical Encyclopedia) Also in Spanish
Clinical Trials
- ClinicalTrials.gov: Blood Cells (National Institutes of Health)
- ClinicalTrials.gov: Hematologic Tests (National Institutes of Health)
Journal Articles References and abstracts from MEDLINE/PubMed (National Library of Medicine)
- Article: Efficacy of ColonFlag as a Complete Blood Count-Based Machine Learning Algorithm...
- Article: Utility of Urinary CD4+ T-Cell Count in Detecting ANCA-Associated Vasculitis Renal...
- Article: CD4+/CD8+ improvement after switch from a second-generation integrase inhibitor regimen to...
- Blood Count Tests -- see more articles
Children
- Complete Blood Count (For Parents) (Nemours Foundation) Also in Spanish
Patient Handouts
- Blood differential test (Medical Encyclopedia) Also in Spanish
- Blood smear (Medical Encyclopedia) Also in Spanish
- CBC blood test (Medical Encyclopedia) Also in Spanish
- Hematocrit (Medical Encyclopedia) Also in Spanish
- Hemoglobin (Medical Encyclopedia) Also in Spanish
- Platelet count (Medical Encyclopedia) Also in Spanish
- RBC count (Medical Encyclopedia) Also in Spanish
- RBC indices (Medical Encyclopedia) Also in Spanish
- WBC count (Medical Encyclopedia) Also in Spanish
The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health.