Quick Facts
- Sample: Whole blood (3 mL in EDTA tube)
- Fasting: Not required
- Turnaround: 1–2 business days. May take longer based on weather, holiday, or lab delays.
Benefits
- Detect infections early — Identifies elevated or abnormal white blood cell patterns that signal bacterial, viral, or other infections
- Diagnose anemia and blood disorders — Pinpoints iron deficiency, vitamin deficiencies, and other blood cell abnormalities
- Track chronic disease and treatment — Monitor kidney disease, chemotherapy effects, and ongoing health conditions
- Screen for overall health — Comprehensive snapshot of your blood health without needing a doctor's appointment
Who Is This Test For?
- People experiencing fatigue, unexplained bruising, or frequent infections
- Anyone seeking routine wellness screening or preventive health monitoring
- Individuals with chronic conditions requiring regular health tracking
- Those monitoring treatment response to medication or therapy
- People with family history of blood disorders or anemia
How It Works – Just 3 Steps
- Order online — No doctor's visit needed; order instantly from home with complete confidentiality
- Visit the lab — Get a simple blood draw at a local lab or arrange at-home collection
- Review results — Receive results within 24–48 hours to guide next steps
FAQ
What does a CBC with Differential measure? This test counts all types of blood cells—red blood cells, white blood cells (broken down by subtype), and platelets—plus measures hemoglobin, hematocrit, and other cell indices to reveal your overall blood health.
Can this test detect infections? Yes. Elevated or decreased white blood cell counts and specific differential patterns (like high neutrophils) reliably indicate infections or immune responses (CDC 2023).
Do I need to fast before this test? No. No fasting or special preparation is required. You can eat and drink normally.
How accurate is the CBC with Differential? The CBC is highly accurate, using automated analysis verified by certified laboratories. Results are reliable for diagnosis and monitoring when interpreted by a healthcare provider.
What if my results are abnormal? Abnormal values may indicate infection, anemia, clotting issues, or immune disorders. Your results include physician guidance, and you should follow up with your healthcare provider for any out-of-range findings.
How soon will I get my results? Typical turnaround is 24–48 hours after your sample reaches the lab.
More Details
What is the purpose of this test?
A Complete Blood Count (CBC) with Differential and Platelet Count evaluates all components of your blood to diagnose infections, anemia, blood disorders, and monitor chronic health conditions (Mayo Clinic 2024). The test measures red blood cells (which carry oxygen), white blood cells (which fight infection), and platelets (which help with clotting). The differential breaks down white blood cells into five subtypes—neutrophils, lymphocytes, monocytes, eosinophils, and basophils—each revealing different aspects of your immune health.
Who would benefit from this test?
Anyone seeking comprehensive health insights benefits from a CBC. This includes people experiencing symptoms like unexplained fatigue, fever, or unusual bruising; those with chronic conditions like kidney disease requiring regular monitoring; individuals on medications or treatments needing effect tracking; and health-conscious people pursuing preventive wellness screening (ASH 2024). It's especially valuable for detecting early-stage anemia, infections, and immune system issues.
When should I order a CBC with Differential and Platelet Count?
Order this test if you're experiencing symptoms like fatigue, fever, frequent infections, unexplained bruising, or swollen lymph nodes. Include it in routine annual health checkups, whenever starting new medications or treatments, when monitoring chronic conditions, or if you have risk factors for blood disorders. Early screening enables timely intervention before symptoms worsen.
How do I interpret the results?
Results are compared to lab-specific reference ranges, which vary slightly between labs. Your report shows individual values with "normal," "low," or "high" flags. Key indicators include hemoglobin (oxygen-carrying capacity), hematocrit (red blood cell percentage), and white blood cell counts and differentials (immune function). Abnormal patterns warrant physician consultation. Here's a quick reference:
WBC (White Blood Cells):
- Normal range: 4,500–11,000/μL
- What it means: Immune cell levels; low may indicate immune suppression; high suggests infection or immune activation
- Typical action: Physician follow-up if abnormal
RBC (Red Blood Cells):
- Normal range: 4.5–5.5M/μL (male); 4.0–5.0M/μL (female)
- What it means: Oxygen-carrying capacity; low indicates anemia; high may indicate dehydration
- Typical action: Evaluate for anemia or volume status
Hemoglobin (Hgb):
- Normal range: 13.5–17.5 g/dL (male); 12.0–15.5 g/dL (female)
- What it means: Oxygen transport; low = anemia; affects energy and fatigue
- Typical action: Iron studies or dietary review if low
Hematocrit (Hct):
- Normal range: 41–53% (male); 36–46% (female)
- What it means: Percentage of blood that is red cells; low = anemia
- Typical action: Investigate underlying cause if low
Platelet Count:
- Normal range: 150,000–400,000/μL
- What it means: Blood clotting ability; low increases bleeding risk; high may increase clotting
- Typical action: Hematology referral if outside range
Neutrophils (absolute):
- Normal range: 2,500–7,000/μL
- What it means: Most common infection-fighting cells; elevation suggests acute infection
- Typical action: Assess for infection source
A CBC often reveals treatable conditions—early detection of hematologic abnormalities can reduce hospitalization by 15% in chronic disease populations (ASH 2024).
Pre-test preparation
No special preparation is needed. You don't need to fast, adjust medications, or restrict food or water intake. Wear loose, comfortable clothing to make the blood draw easier. If you're anxious about needles, let the phlebotomist know. Collect your sample at a convenient local lab or arrange at-home collection at a time that works for you.
How often should I get tested?
Testing frequency depends on your health status, symptoms, and medical history. Use this guide:
- Routine wellness screening (no symptoms): Annually or every 2 years
- Monitoring chronic disease (kidney, liver, cancer): Every 3–6 months or per physician guidance
- On active treatment (chemotherapy, medications): Every 1–4 weeks per treatment protocol
- Symptoms present (fatigue, fever, bruising): Immediately, then repeat based on results
- After abnormal result: 2–4 weeks for follow-up; interval depends on findings
- Family history of blood disorders: Annually or per physician recommendation
Why early detection matters
Anemia affects approximately 1.62 billion people globally, yet many remain undiagnosed (WHO 2023). Early CBC screening catches iron deficiency, vitamin deficiencies, and other blood disorders before symptoms become severe. Early detection of hematologic abnormalities can reduce hospitalization by 15% in chronic disease cohorts (ASH 2024). The CBC differential improves diagnostic sensitivity for infections by identifying white blood cell subtype elevations, enabling faster treatment and better outcomes (Journal of Clinical Pathology 2022).
Related tests you may consider
Anemia #1 Baseline Blood Test Panel — Complements RBC findings to determine if anemia is due to iron deficiency, helping guide nutritional or medical treatment.
Vitamin B12 and Folate Blood Test Panel — Identifies deficiencies affecting blood cell production, especially important if your CBC shows macrocytic anemia.
C-Reactive Protein (CRP) Blood Test, High Sensitivity, Cardiac Risk Assessment — Provide additional insights into infection, inflammation, or autoimmune activity when CBC results suggest immune activation.
