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UW Health SMPH
American Family Children's Hospital

UW Hospital and Clinics Lab Test Directory

Test Name: White Cell Count

Test Code(s): WBC

CPT Code(s): 85048

Test Description: Included In: White Cell Count and Differential, CBC with Differential, CBC without Differential

Methodology: Flow Cytometry and Impedance

Days Performed: Daily, 24 hours.

Turnaround Time: Stat: 1 hour.
Routine: 4 hours.

Specimen Requirements

Specimen: Blood

Collection Container: Preferred: K3EDTA-Lavender top
Also Acceptable: K2EDTA-Lavender top, Pink top tube

Collection Volume: Preferred: 4 mL
Pediatrics: 1 mL

Sample Analyzed: Whole Blood

Volume Required: Preferred: 1 mL
Pediatrics: 0.25 mL in microtainer

Specimen Transport: Transport specimen to laboratory at ambient temperature.

Unacceptable Criteria: Clotted specimens are not acceptable.Tubes with <25% of fill volume.

Stability: Ambient: 24 hours
Refrigerated: Not acceptable
Frozen: Not acceptable


Reference Interval:



0-29 days  9.1-34.0    
30 days - 23 months  6.0-14.0    
2-9 years  4.0-12.0    
10-17 years  4.0-10.5    
18 years and up  3.8-10.5    

Critical Calls: View

white blood cell

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