Test ID XHIM X-Linked Hyper IgM Syndrome, Blood
Useful For
Screening for X-linked hyper-IgM (XL-HIGM) or CD40L deficiency, primarily in male patients younger than 10 years of age
Ascertaining XL-HIGM carrier status in women of child-bearing age (younger than 45 years old)
Genetics Test Information
CD40LG is located on the long arm of the X-chromosome (Xq 21.3-22) and encodes the surface protein CD40 ligand (CD154). It is critical for the formation of germinal centers and, therefore, class switch recombination and somatic hypermutation. More than 100 unique genetic variants of CD40LG have been described. The observed variants are scattered throughout the gene but are more prevalent in exon 5.
Method Name
Flow Cytometry
Reporting Name
X-Linked Hyper IgM Syndrome, BSpecimen Type
WB Sodium HeparinShipping Instructions
Specimens are required to be received in the laboratory weekdays and by 4 p.m. on Friday. Collect and package specimen as close to shipping time as possible.
It is recommended that specimens arrive within 24 hours of collection.
Specimens arriving on the weekend and observed holidays may be canceled.
Specimens received more than 72 hours after collection will be rejected and the assay will not be performed.
Necessary Information
Ordering physician's name and phone number are required.
Specimen Required
Container/Tube: Green top (sodium heparin)
Specimen Volume: 4 mL
Collection Instructions: Send specimen in original tube. Do not aliquot.
Additional Information: For serial monitoring, it is recommended that specimen collection be performed at the same time of day.
Specimen Minimum Volume
1.2 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
WB Sodium Heparin | Ambient | 72 hours | GREEN TOP/HEP |
Reference Values
Present
Day(s) Performed
Monday through Friday
Performing Laboratory

CPT Code Information
88184-Flow cytometry, cell surface, cytoplasmic
88185 x 6-Each additional marker
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
XHIM | X-Linked Hyper IgM Syndrome, B | 98239-7 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
82964 | CD40 Ligand Expression | 98240-5 |
29040 | CD40muIg (Function) | 98241-3 |
23901 | Interpretation | 69052-9 |