RhE/e (RHCE) Antigen Genotyping, Fetal

Casandra

Casandra Test Code AR06837Version 1 (DRAFT)

Performing Lab

Lab ARUP LaboratoriesLab Test ID 3016682CPT Codes 0001, 81265

RhE/e (RHCE) Antigen Genotyping, Fetal

Also known as: RHEGENO FE

Clinical Use

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Use

Fetal RhE/e genotyping is performed to assess the risk for alloimmune hemolytic disease of the fetus and newborn (HDFN). This genotyping evaluates the presence of Rh blood group antigens E and e, which are significant in predicting the antigen expression and potential for hemolytic disease from the maternal antibodies transferred to the fetus. Understanding the fetal RhEe genotype helps determine the risk for anti-e-mediated alloimmune hemolytic disease, which is characterized by red-cell hemolysis due to incompatibility between the maternal antibodies and fetal erythrocytes.

Special Instructions

Not provided.

Limitations

The assay may not detect rare nucleotide changes leading to altered or partial antigen expression and null phenotypes. False-negative results can occur due to bloody amniotic fluid samples contaminating with maternal cells or RHCE-D-CE fusion genes. The test is limited in predicting genotype due to extreme variation in the Rh locus. Patients who have had hematopoietic stem cell transplants may yield inconclusive results. Additionally, abnormal signal intensities can result in indeterminate genotyping outcomes. The test was developed and its performance characteristics determined by ARUP Laboratories; it is not FDA-cleared or approved, though performed in a CLIA certified laboratory for clinical purposes.

Test Details

New York Approved