Components of Complete Blood Count (CBC) and Comprehensive Metabolic Panel (CMP)
A Complete Blood Count (CBC) includes measurements of red blood cells, white blood cells, and platelets, while a Comprehensive Metabolic Panel (CMP) assesses kidney function, liver function, electrolyte balance, and blood glucose levels.
Complete Blood Count (CBC) Components
The CBC is one of the most commonly ordered laboratory tests in medicine 1. It evaluates the total numbers and characteristics of cellular components in the blood and includes:
Red Blood Cell Parameters
- Red Blood Cell (RBC) count
- Hemoglobin (Hb)
- Hematocrit (Hct)
- Red Blood Cell Indices:
- Mean Corpuscular Volume (MCV)
- Mean Corpuscular Hemoglobin (MCH)
- Mean Corpuscular Hemoglobin Concentration (MCHC)
- Red Cell Distribution Width (RDW)
- Reticulocyte count (when ordered)
White Blood Cell Parameters
- White Blood Cell (WBC) count
- WBC differential, which includes:
- Neutrophils (absolute count and percentage)
- Lymphocytes (absolute count and percentage)
- Monocytes (absolute count and percentage)
- Eosinophils (absolute count and percentage)
- Basophils (absolute count and percentage)
Platelet Parameters
- Platelet count
- Mean Platelet Volume (MPV)
Comprehensive Metabolic Panel (CMP) Components
The CMP provides crucial information about the body's chemical balance and metabolism 1. It includes:
Electrolytes
- Sodium
- Potassium
- Chloride
- Carbon dioxide (CO2, bicarbonate)
Kidney Function Tests
- Blood Urea Nitrogen (BUN)
- Creatinine
- BUN/Creatinine ratio (calculated)
Liver Function Tests
- Albumin
- Total protein
- Bilirubin
- Alkaline phosphatase (ALP)
- Aspartate aminotransferase (AST)
- Alanine aminotransferase (ALT)
Glucose Metabolism
- Glucose (blood sugar)
Calcium
- Calcium level
Clinical Significance and Applications
CBC Applications
- Screening for anemia, infection, and hematologic disorders
- Monitoring disease progression and treatment response
- Preoperative evaluation
- Monitoring for medication side effects
- Evaluating bleeding or clotting disorders
- Assessing immune system function
CMP Applications
- Evaluating kidney and liver function
- Monitoring electrolyte balance
- Screening for diabetes and prediabetes
- Assessing nutritional status
- Monitoring effects of medications on organ function
- Evaluating acid-base balance
Important Considerations
- Both tests are often ordered together as part of routine health screenings or when evaluating specific symptoms or conditions
- Results should be interpreted in the context of the patient's clinical presentation
- Abnormal values may require follow-up testing for confirmation and diagnosis
- Reference ranges may vary slightly between laboratories
- Certain medications, hydration status, and fasting state can affect test results
These comprehensive panels provide valuable information about a patient's overall health status and are essential tools in diagnosing and monitoring various medical conditions.