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Test Code CBCWMDIFF Complete Blood Count (CBC) With Manual Differential, Blood

Additional Codes

St. Luke's Compendium Code (Iatric): L100.0050

Performing Laboratory

St. Lukes Hospital Laboratory

Methodology

Automated Flow-Through Cytometry

Includes RBC count, WBC count, hemoglobin, hematocrit, MCV, MCH, MCHC, RDW, platelet count, MPV, and 5-part manual differential including % values for neutrophils, lymphocytes, monocytes, eosinophils, and basophils.

Specimen Requirements

Draw blood in a lavender-top (EDTA) tube(s), and send 1 mL of EDTA whole blood. If there is a delay in transport of >8 hours, make 4 to 5 blood smears within 2 hours of draw. Forward promptly at ambient temperature. Label slides with patient’s full name (first and last) and date and time of collection.
Note: If specimen will not arrive at St. Luke’s Hospital Laboratory the same day as drawn, refrigerate specimen. Transport at ambient temperature. Do not place EDTA whole blood directly on top of an ice pack. Stored at 2 – 8 C, EDTA blood samples with normal results may be analyzed up to 48 hours without significant loss of differential stability; Retic stability 48 hours. Sample stability at room temperature is 24 hours.  Samples stored at room temperature may exhibit an increase in MCV after 24 hours, which may be minimized by refrigeration.

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Reference Values

Reference ranges are age- and sex-specific. See report.

Hematology differentials that fit the following criteria will be referred to a hematopathologist:

—Markedly abnormal RBC morphology (many target cells, spherocytes, schistocytes, etc.)

—Greater than 3 nucleated RBCs (excluding newborns)

—If the WBC is <1,000/cmm or >30,000/cmm

—If immature WBCs are present (promyelocytes or blasts)

—If the number of lymphocytes is >7,500/cmm

—If the number of platelets is <20,000/cmm or >750,000/cmm

—If the hemoglobin is <7 g/dL or >19 g/dL

—Presence of organisms

Interfering Substances:

Lipemia, hemolysis, abnormal RBC morphology, and cold agglutinins may interfere with testing.

Day(s) Test Set Up

Monday through Sunday

Test Classification and CPT Coding

85007 - blood smear, microscopic examination with manual differential WBC count

85027 - CBC, automated (Hgb, Hct, RBC, WBC and platelet count)