Understanding Your Diagnostic Test: What It Is, How It Is Performed, and Why You May Need It
This test counts basophils (a type of white blood cell) in the fluid surrounding the heart to help diagnose the cause of fluid accumulation.
{"The test examines fluid from around the heart (pericardial fluid)","Basophils are white blood cells that help fight infections and allergic reactions","Abnormally high basophil counts may indicate infection, inflammation, or other conditions","The test is performed by examining the fluid under a microscope","Results help doctors determine the cause of pericardial effusion (fluid around the heart)"}
Key facts at a glance
- LOINC
- 31994-7
- Short code
- BASPC
- Synonyms
- Basophils NFr Pcar Manual
- Category
- chemistry
- Sample
- serum
- Container
- Sterile plain tube or EDTA tube for cell count; no anticoagulant preferred for cytology
- Units
- N/A
- Ref low
- 0
- Ref high
- 1
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 0–120 years
- Method
- manual-count
- CPT
- 89051
- SNOMED
- 44169004
- Specimen volume
- 1-5 mL of pericardial fluid minimum; larger volumes preferred when available
- Stability
- Analyze within 1 hour of collection at room temperature for accurate cell counts; refrigerate at 2-8°C if delayed beyond 1 hour (analyze within 4 hours)
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 1–4 hours
- Order
- routine
This test is a diagnostic procedure that gives your healthcare provider important information about how your body is working. It may involve collecting a small sample, such as blood or urine, or using imaging technology, and the results help guide decisions about your care.
The Basophil Count in Pericardial Fluid test is a laboratory examination that counts the number of basophils (a type of white blood cell) in a sample of fluid taken from around the heart. This fluid is called pericardial fluid, which naturally exists in small amounts in the pericardial sac surrounding the heart. When too much fluid accumulates (a condition called pericardial effusion), doctors may need to drain it and analyze it to determine the cause.
The test is usually performed in a doctor's office, clinic, or hospital by a trained member of your care team. You may be asked to sit or lie down while a sample is collected or while equipment is positioned over the area being examined. The procedure is typically quick, and most people feel little or no discomfort.
A doctor will collect pericardial fluid through a procedure called pericardiocentesis, where a needle is inserted into the pericardial sac to withdraw fluid. The sample is then sent to a laboratory where a technician examines it under a microscope to manually count the basophils and other cells present. This is called a manual differential cell count.
Your doctor may recommend this test to help find the cause of symptoms you are experiencing, to screen for a condition before it causes problems, to monitor an illness you already have, or to check how well a treatment is working. The results help your care team plan the next steps in your treatment.
Your doctor may order this test if you have symptoms of pericardial effusion, such as chest pain, difficulty breathing, or a feeling of fullness in the chest. The test helps determine whether the fluid accumulation is due to infection, cancer, inflammation, or other medical conditions.
Reference range
No established reference range; results interpreted in clinical context. Pericardial fluid is normally a transudate with minimal cellularity. Basophils are typically absent or extremely rare in normal pericardial fluid.N/A
Pericardial fluid is obtained via pericardiocentesis performed by a qualified physician under sterile conditions. No patient fasting is required prior to pericardiocentesis. Informed consent must be obtained before the procedure.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Basophils are white blood cells that play a role in the body's immune response, particularly in allergic reactions and fighting parasitic infections. Elevated basophil counts in pericardial fluid may indicate: bacterial or viral infections, inflammatory conditions like pericarditis, certain cancers such as leukemia or lymphoma, or autoimmune disorders. The presence of many basophils along with other inflammatory cells helps doctors narrow down the possible causes of pericardial effusion and guide appropriate treatment.
Frequently asked questions
Is the test painful?
How long does it take to get results?
What do abnormal results mean?
Are there any risks from the test?
Sources
- 1
- 2
- 3
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy