Rh Genotyping, Rh C,D,E (Sendout)

Interpretation

Method

Polymerase Chain Reaction (PCR) based

Reference Range

See individual components

Ref. Range Notes

See report.

Interferences and Limitations

Molecular testing to predict the red blood cell phenotype does not always reflect the phenotypic expression of the blood group antigen. This may occur in cases where the individual has genetic variation that silences or alters the blood group antigen expression that is not included in the target region of the test, and also may occur with RhD zygosity testing. Test results must be interpreted with knowledge of how known polymorphisms affect blood group antigen expression.

References

• Bloodworks Northwest Test Information: Rh Genotyping- Rh C,D,E Systems

Ordering & Collection

Specimen Type

Whole Blood, Cultured Amniocytes

Collection

Whole Blood: 10 mL whole blood in LAVENDER TOP (EDTA) tube

• Note: For very difficult draws, contact the Genomics Testing Lab at Bloodworks NW at (206) 689-6269 for approval of microtainers.

Cultured Amniocytes: 2 T25 Flasks cultured to confluency.

• Amniotic fluid is not accepted.
• An EDTA whole blood sample from the mother of the fetus must accompany cultured amniocyte orders.

Labeling Requirements:

• The sample label and requisition must contain two matching identifiers, one being the full name, and the second a numeric identifier like hospital ID/MRN.
• A matching draw date must be included on the specimen label and the requisition form.

Samples sent on Fridays must be received at Bloodworks Northwest Genomics Lab by 1 p.m.

Forms & Requisitions

• Bloodworks Northwest Genomics Testing Laboratory Requisition

Handling Instructions

Outside Laboratories:

• Store and transport whole blood at ambient temperature.
• Expedite transport; samples must be received by Bloodworks NW within 48 hours of collection and before 1 p.m. on Fridays. Allow for one day of transport from UW-MT to Bloodworks Northwest.
  • Unless the cells are cultured at UW-MT Cytogenetics and Genomics Lab, clients should arrange to send cultured amniocyte samples directly to Bloodworks NW due to the short stability window (24 hours).
• Submit a completed Bloodworks Northwest Genomics Testing Laboratory Requisition along with the DLMP Requisition.* Leave the billing section blank to be completed by Sendouts staff.
  • *Use client-specific requisition when available. To obtain a client-specific requisition, contact Client Support Services via email at: commserv@uw.edu.

Stability:

• Cultured Amniocytes: Ambient: 24 hours.
• Whole Blood: Ambient: 48 hours.

Quantity

Requested: 10 mL EDTA whole blood or 2 x T25 flasks of cultured amniocytes
Minimum: 5 mL EDTA whole blood or 2 x T25 flasks of cultured amniocytes

Processing

Receiving Instructions

Store and transport whole blood or cultured amniocytes at ambient temperature.

• Cultured amniocytes should be sent out same-day.
• If the sample is collected on a Friday, notify Sendouts immediately upon sample receipt to ensure delivery to Bloodworks NW by the 1 p.m. cutoff.

Sendouts:

• Order Bloodworks NW Test: 3117-02.
• A completed Bloodworks Northwest Genomics Testing Laboratory Requisition must accompany all orders.
  • The sample label and requisition must contain two matching identifiers, one being the full name, and the second a numeric identifier like hospital ID/MRN.
  • A matching draw date must be included on the specimen label and the requisition form.
• Affix CAST "Billing" and "Results To" labels to the outgoing requisition.
• Package sample(s) with the associated requisition in a biohazard bag (one patient per bag). Orders received with multiple patient samples/requisitions in the same biozard bag will be rejected by Bloodworks NW.
• Send orders as received with the UW DLMP or Delivery Express courier.
• Cultured amniocytes must be sent same-day to the Bloodworks Central Genomics Lab (921 Terry Ave, Seattle WA 98104).
• Samples may be sent Monday through Friday only. If sent on a Friday, samples must be in lab by 1 p.m.
• Ambient whole blood samples must arrive at Bloodworks within 48 hours of collection, and cultured amniocytes within 24 hours of collection.*

Stability:

• Cultured Amniocytes: Ambient: 24 hours.
• Whole Blood: Ambient: 48 hours.

*Contact the Bloodworks NW Genomics Lab at (206) 689-6269 for sample acceptability questions prior to cancelling orders outside of the stated stability window.

Misc Sendout

Performance

Lab Department

Sendouts(SO)

Frequency

Analytic Time: 3 business days from sample receipt at Bloodworks Northwest.

Available STAT?

No

Performing Location(s)

Sendout	Bloodworks Northwest Platelet Immunology/Genomics Laboratory (Central HPG) 921 Terry Ave 6th Floor - SDL Seattle, WA 98104	Genomics Testing Laboratory (for RBC genotyping): (206) 689-6269 Platelet Immunology Laboratory: (206) 689-6543 Laboratory staffed for questions Monday through Friday, 08:00 am to 04:30 pm.

Billing & Coding

CPT Codes

81479

LOINC

18717-9