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Test Code WBC White Blood Count

Useful For

A WBC count is a blood test to measure the number of white blood cells (WBCs) in the blood. WBCs also called leukocytes help to fight infections and are also included in CBC counts.

Collection Method

Venous draw, Capillary Draw

Minimum Volume

Adult: 1 mL, Pediatric 300 uL

Container

Purple (EDTA)

Preferred Specimen

Whole Blood

Acceptable Specimens

EDTA Whole Blood, BD EDTA MAP tube

Reference or Target Ranges

Males   Females    
Birth 9.00 – 30.00 × 109/L Birth 9.00 – 30.00 × 109/L
1 – 7 days 9.40 – 34.00 × 109/L 1 – 7 days 9.40 – 34.00 × 109/L
8 – 14 days 5.00 – 21.00 × 109/L 8 – 14 days 5.00 – 21.00 × 109/L
15 days – 1 month 5.00 – 20.00 × 109/L 15 days – 1 month 5.00 – 20.00 × 109/L
2 – 5 months 5.00 – 15.00 × 109/L 2 – 5 months 5.00 – 15.00 × 109/L
6 months – 2 years 6.00 – 11.00 × 109/L 6 months – 2 years 6.00 – 11.00 × 109/L
2 years 5.00 – 12.00 × 109/L 2 years 5.00 – 12.00 × 109/L
3 – 5 years 4.00 – 12.00 × 109/L 3 – 5 years 4.00 – 12.00 × 109/L
6 – 11 years 3.40 – 9.50 × 109/L 6 – 11 years 3.40 – 10.80 × 109/L
12 – 15 years 3.60 – 9.10 × 109/L 12 – 15 years 4.10 – 8.90 × 109/
Adults 3.50 – 10.50 × 109/L Adults 3.50 – 10.50 × 109/L

Reportable Units

x 109 /L

Critical Value

Parameter Low value High value
White Blood Cells (0 – 18 years) <2 × 109/L >50 × 109/L
White Blood Cells (>18 years) <1 × 109/L >80 × 109/L

Reasons for Rejection

Hemolysis Threshold N/A
Icterus Threshold N/A
Lipemia Threshold N/A
Other Clotted; QNS, Contaminated; improperly labeled

Specimen Stability

Ambient Up to 24 hours at room temperature
Refrigerated (4°C to 8°C) 24 Hours
Frozen(-70°C to 0°C) N/A

Performance Information

Days and Time Performed 24/7
Expected Turn Around Time Stat within 1 hour arrival in lab
Routine within 4 hours of arrival in lab
Stat Availabilty Yes
Performing Bench UH, WCH Hematology
Methodology/Method Description Sysmex – The WBC counts are evaluated using flow cytometry with a semiconductor laser.

Special Handling

Room Temp

CPT Codes

85048