Table II.

Indications for red cell genotyping.

Appropriate	Possible	Not feasible at this time
Chronically-transfused patient*	Haematology-oncology patient	Surgical patient
Patient with multiple alloantibodies	Oncology patient (non-haematological)	Trauma patient at presentation†
Patient with autoimmune haemolytic anaemia	Patient with a single blood group alloantibody	All transfused patients
Patient with an alloantibody to a high prevalence antigen	Donor and recipient in hematopoietic progenitor cell transplantation
Foetus in a mother with an alloantibody‡	Patient with advanced renal failure
Search for donors with rare phenotypes	Patient with advanced hepatic failure
Sample with a phenotyping discrepancy or difficulty
Reagent red blood cell development and testing

^*For example, one with sickle cell disease, thalassaemia, myelodysplastic syndrome, or aplastic anaemia;

^†consider buccal swaps in some situations;

^‡intrauterine foetal transfusions matched to the mother’s antigens to prevent further alloimmunisation.