RhC/c (RHCE) Antigen Genotyping, Fetal
Also known as: RHCGENO FE
Use
Fetal RhC/c genotyping is used to assess the risk for alloimmune hemolytic disease, which can lead to hemolytic transfusion reactions or hemolytic disease of the fetus and newborn (HDFN). The test determines the fetal RhCc genotype to predict the expression of specific Rh antigens, thereby evaluating potential risks associated with maternal sensitization to these antigens. The clinical sensitivity of the test is reported to be 99 percent.
Special Instructions
Informed consent for genetic testing is required for patients from New York. If the client is unable to culture, they should order the 'Cytogenetics Grow and Send' test (ARUP test code 0040182) in addition to this test. Contact ARUP's Genetics Processing for further questions. Counseling and informed consent are recommended for genetic testing, and consent forms are available online.
Limitations
This test may yield false-negative results if the amniotic fluid specimens contain maternal cell contamination. Rare nucleotide changes leading to altered or partial antigen expression may not be detected. Genotypes resulting in Rh null phenotypes or extreme variation in the Rh locus may also be inadequately assessed. False-negative predictions may occur due to RHCE-D-CE fusion genes, and those who have had hematopoietic stem cell transplants may receive inconclusive results. Abnormal signal intensities might lead to indeterminate genotyping results.
New York Approved
Methodology
PCR-based (RT-PCR)
Biomarkers
LOINC Codes
- 31208-2
- 46731-6
- 59266-7
- 66746-9
Result Turnaround Time
3-10 days
Related Documents
For more information, please review the documents below
Specimen
Amniotic Fluid
Volume
10 mL
Minimum Volume
5 mL
Container
sterile container
Storage Instructions
CRITICAL ROOM TEMPERATURE. Must be received within 48 hours of shipment due to lability of cells.
Causes for Rejection
Frozen specimens in glass collection tubes.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 48 hours |
| Refrigerated | 48 hours |
| Frozen | Unacceptable |
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