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UW Health SMPH
American Family Children's Hospital

UW Hospital and Clinics Lab Test Directory

Test Name: Reticulocyte Count

Test Code(s): RTC / RET

CPT Code(s): 85045

Methodology: Fluorescence

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:


Absolute Reticulocyte:  
 Ages 0-3 days

147 - 216 K/uL

 Ages 4 days and up  30 - 115  K/uL

 Immature Reticulocyte Fraction

  Ages 4 days and up

  0.0 - 25.0%





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