Test Code CD40 B-Cell CD40 Expression by Flow Cytometry, Blood
Reporting Name
CD40 by Flow, QL, BPerforming Laboratory
Mayo Clinic Laboratories in RochesterUseful For
Evaluating patients for hyper-IgM type 3 (HIGM3) syndrome due to defects in CD40, typically seen in patients less than 10 years
Assessing B-cell immune competence in other clinical contexts, including autoimmunity, malignancy, and transplantation
Method Name
Flow Cytometry
Ordering Guidance
This test is not used to detect in CD40L expression (CD154), which is responsible for X-linked hyper-IgM syndrome (HIGM1); see XHIM / X-Linked Hyper IgM Syndrome, Blood.
Shipping Instructions
Testing performed Monday through Friday. Specimens not received by 4pm (CST) on Friday may be cancelled.
Collect and package specimen as close to shipping time as possible. It is recommended that specimens arrive within 24 hours of collection.
Samples arriving on the weekend and observed holidays may be canceled.
Necessary Information
Ordering healthcare professional name and phone number are required.
Specimen Required
Container/Tube: Lavender top (EDTA)
Specimen Volume: 3 mL
Collection Instructions: Send whole blood specimen in original tube. Do not aliquot.
Additional Information: For serial monitoring, it is recommended that specimens are collected at the same time of day.
Specimen Type
Whole Blood EDTASpecimen Minimum Volume
1 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Whole Blood EDTA | Ambient | 72 hours | PURPLE OR PINK TOP/EDTA |
Reject Due To
Gross hemolysis | Reject |
Gross lipemia | Reject |
Reference Values
Present (normal)
Interpretation
This assay is qualitative; CD40 expression is reported as present (normal) or absent (abnormal). Normal B cells express surface CD40 on the majority of cells.
Hyper-IgM (HIGM3) syndrome patients typically do not express CD40 on the surface of B cells. Genotyping of CD40 is required for a definite diagnosis of HIGM3. Call 800-533-1710 for ordering assistance.
Day(s) Performed
Monday through Friday
Report Available
3 to 4 daysTest Classification
This test was developed using an analyte specific reagent. Its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
88184
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
CD40 | CD40 by Flow, QL, B | 104694-5 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
89009 | CD40 by Flow, QL, B | 104694-5 |