Neutrophil to Lymphocyte Ratio (NLR), Complete Blood Count (CBC) With Differential and Platelet
Also known as: CBC/D/Plt+NLR
Use
NLR (Neutrophil to Lymphocyte Ratio) is a biomarker that can be used as an indication of subclinical inflammation. NLR is a calculation based on the Absolute Neutrophil Count divided by the Absolute Lymphocyte Count determined by the peripheral blood CBC differential. This calculation, according to recent literature, is useful in assessing the likelihood of severe progression of disease in SARS-CoV-2 positive patients.
Special Instructions
The test includes a detailed six-part differential in some lab locations, which includes assessments like IG % and IG absolute counts, and separate reporting of bands and blasts. Smear evaluations are triggered by specific numeric or instrument flagging criteria, with potential follow-up required based on initial findings.
Limitations
Turnaround time may vary and not all sites may perform the six-part differential. Elevated IG percentages alone aren't clinically significant as sole predictors but are associated with conditions such as infections, inflammatory disorders, and medications like steroids. Pregnancy may also alter results due to physiological changes.
Methodology
Automated Analyzer (Hematology)
Biomarkers
LOINC Codes
- 6690-2
- 789-8
- 718-7
- 4544-3
- 787-2
- 785-6
- 786-4
- 788-0
- 777-3
- 770-8
- 736-9
- 5905-5
- 713-8
- 706-2
- 75652-8
- 751-8
- 731-0
- 742-7
- 711-2
- 704-7
- 71695-1
- 53115-2
- 58413-6
- 18314-5
Result Turnaround Time
1 day
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
Fill tube to capacity.
Minimum Volume
0.5 mL (500 μL for pediatric microtainer capillary tubes; fill tube to capacity)
Container
Lavender-top (EDTA) tube
Collection Instructions
Invert tube 8 to 10 times immediately after tube is filled at the time of collection.
Storage Instructions
Maintain specimen at room temperature.
Causes for Rejection
Hemolysis; clotted specimen; specimen drawn in any anticoagulant other than EDTA; specimen diluted or contaminated with IV fluid; tube not filled with minimum volume; improper labeling; transfer tubes with whole blood; specimen received with plasma removed
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 1 day |
| Refrigerated | 3 days |
| Frozen | Unstable |
