Competency: 17

Details

Undertake follow-up in antenatal cases with red cell antibodies, including additional serological testing, referral to specialist units, paternal typing (and fetal genotyping where appropriate).

Report results in clinical context, recognising the need for referral, and communicating with clinicians and midwives.

Considerations

• Aetiology, and clinical presentation of HDFN, and the specificities of red cell antibodies implicated.
• The antenatal testing requirements of those antibodies known to cause HDFN:
  • anti-D
  • anti-c
  • Kell-related antibodies.
• Prediction of risk/severity of HDFN from laboratory testing during pregnancy:
  • titration of antibodies and the selection of cells and reagents to perform the titration
  • quantification of antibodies
  • significant levels for anti-D, anti-c, anti-K and other potentially clinically significant red cell antibodies
  • which specificities do not cause HDFN and why
  • role of immunoglobulin class and subclasses in the severity of HDFN
  • phenotyping of the father to predict the phenotype of the fetus and likelihood of HDFN
  • the criteria and limitations when free fetal DNA testing for the fetal genotype can be employed
  • non-serological monitoring of the fetus throughout pregnancy, e.g. middle cerebral artery Doppler and ultrasound.
• The significance of a positive DAT in a neonatal sample.
• Strategies for the reduction of impact on the fetus of HDN:
  • IUT
  • premature delivery
  • exchange transfusion, top-up transfusions and phototherapy
  • new and emerging strategies.
• Logistics of ongoing support throughout pregnancy and delivery for women requiring rare blood and liaison with reference services.
• Additional specifications of units suitable for IUT, neonatal top-up and neonatal exchange.
• Cross-matching considerations for neonates.

Relevant learning outcomes