Test Code DIFF Differential Count
Specimen Type
Blood
Container/Tube
Lavender top, EDTA
Turnaround Time
8 hours
STAT Days and Times Performed
24/7
Days and Times Performed
24/7
Method Name
Sysmex XN automated hematology analyzer and Wright stain light microscopy
Test Includes
Manual and Automated WBC Differentials include percentage and absolute number of White Blood Cell types, RBC morphology, WBC Morphology and platelet estimate. Performed manually or automated per laboratory protocol.
To ensure absolute values are reported, please order a CBC and a
DIFF. Automated Differentials that are released without review by
technologist only include percentage and absolute number of WBC
cell types.
The percentage of cells reported in a WBC Differential is based on counting 100 white blood cells. If the WBC is >15 x10³/µL, a 200 cell count is performed the percentage of each cell type counted is calculated (extrapolated to 100) and reported with the number of cells counted. When the WBC is very low (<1.5 x10³/µL) less than 100 cells are counted the percentage of each cell type counted is calculated (extrapolated to 100) and reported with the number of cells counted.
Only those cells seen during the count are reported. If the cell type is not reported, there were none of the cell type seen. For example, if 60% Neutrophils, 25% Lymphocytes, 12% Monocytes, 2% Eosinophils, 1% Basophils are reported; then no other cells (reactive lymphs, metamyelocytes, myelocytes, promyelocytes, blasts) were seen.
Preferred Volume
4 mL
STAT Turnaround Time
90 minutes
Critical Results
- WBC: <1.0 or >30.0 (x 10³/µL)
- White Cell Differential: <0.5 Combined Neutrophil when WBC is > 1.0 (x 10³/µL)
- White Cell Differential: >4% blasts on outpatient or emergency room patient
- Any intracellular bacteria /yeast/ parasites present
Coverage Information
CMS has established a national coverage policy (NCD) for
Medicare for this test as of November 25, 2002. Please document
medical necessity. For more details click this
link:
https://www.cms.gov/medicare-coverage-database/details/ncd-details.aspx?NCDId=61&ncdver=1&bc=AgEAAAAAAAAA
Fee Code
53236
Synonyms
WBC Differential
UCMC Collection Instructions
Specimen must be received within 8 hours of collection.
Refrigerate sample if transportation is delayed
Specimen Minimum Volume
- 2 mL blood in 4 mL tube
- 1.5 mL blood in 3 mL tube.
- If a microvette is collected, the minimum volume is 250 µL
CPT
85004
Reference Values
Parameter |
Percentage (%) | Absolute (K/uL) |
Neutrophils/Granulocytes |
39-75 | 1.12-6.72 |
Bands | 0 – 6 | 0-0.66 |
Bands are counted on patients 6 years old and on all ED patients. On all other patients, “Left Shift” will be reported if Bands are 10% based on scan of the blood smear. | ||
Lymphocytes |
16-47 | 0.9-3.30 |
Monocytes |
4 – 12 | 0.16-0.92 |
Eosinophils |
0-7 | 0.0-0.6 |
Basophils |
0-2 | 0.0-0.21 |
Immature Granulocyte | <0.5 | <0.04 |
Reference ranges confirmed November, 2009
Test Limitations
Transportation temperature: specimen cannot be frozen or
heated
Rejection criteria: clotted or short specimen volume; microclot
formation; improper tube
Specimen must be received within 8 hours of collection. Refrigerate
sample if transportation is delayed