Sign in →

Test Code CD20 CD20 B Cells by Flow Cytometry

Useful For

Please see the Flow Cytometry Flow Chart for ordering instructions
Assessing therapeutic B-cell depletion quantitatively (% and absolute counts of cells/mcL) in any clinical context, including malignancies, autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus, and membranous glomerulonephritis among others, and treatment or prevention of acute humoral rejection in positive crossmatch renal transplant recipients (i.e. Rituximab therapy).
Evaluation of CD19 deficiency in patients with a suspected CD19 deficiency (humoral immunodeficiency)
Confirming complete absence of B cells in suspected primary humoral immunodeficiency’s using both CD19 and CD20 markers
Assessing therapeutic B-cell depletion quantitatively (% and absolute counts of cells/mcL) in any clinical context, including malignancies, autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus, and membranous glomerulonephritis among others, and treatment or prevention of acute humoral rejection in positive crossmatch renal transplant recipients (i.e. Rituximab therapy).
Evaluation of CD19 deficiency in patients with a suspected CD19 deficiency (humoral immunodeficiency)
Confirming complete absence of B cells in suspected primary humoral immunodeficiency’s using both CD19 and CD20 markers
Assessing therapeutic B-cell depletion quantitatively (% and absolute counts of cells/mcL) in any clinical context, including malignancies, autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus, and membranous glomerulonephritis among others, and treatment or prevention of acute humoral rejection in positive crossmatch renal transplant recipients (i.e. Rituximab therapy).
Evaluation of CD19 deficiency in patients with a suspected CD19 deficiency (humoral immunodeficiency)
Confirming complete absence of B cells in suspected primary humoral immunodeficiency’s using both CD19 and CD20 markers

Patient Preparation

No special patient preparation required

Collection Method

Venous draw

Minimum Volume

2 mL

Container

Purple (EDTA)

Preferred Specimen

Whole Blood

Acceptable Specimens

EDTA Whole Blood

Reference or Target Ranges

Provided on report

Reportable Units

cells/μL

Critical Value

Not defined for this assay

Reasons for Rejection

 

 

Hemolysis Threshold N/A
Icterus Threshold N/A
Lipemia Threshold N/A
Other QNS, contaminated, improperly labled, improper specimen type, specimen clotted

Specimen Stability

Ambient 24 hours
Refrigerated (4°C to 8°C) Do not refrigerate
Frozen(-40°C to 0°C) Do not freeze

Performance Information

 


<!-- Performance information -->

 

Days and Time Performed Monday – Friday 9AM – 5PM
 
Expected Turn Around Time 24 hours
Stat Availabilty No
Performing Bench Flow Cytometry
Methodology/Method Description BD FACSCanto II – Flow Cytometry, Dual Platform (CBC w. CD19, CD20, CD45)

Additional Information/Important Notes

This is the correct test to order if specifically confirming the absence of B cells due to CD20 targeted immunotherapy, suspected primary humoral, combined immunodeficiency or evaluating for CD19 deficiency. This will not detect a malignancy.
If desirous of testing for a suspected B-cell lymphoma or leukemia, order Flow LLI (Leukemia Lymphoma immunophenotyping). For quantitative subsets (T/B/NK) order T/B Qn flow.

CPT Codes

86355