THE Rh BLOOD GROUP SYSTEM

139 CHAPTER10139 THE Rh BLOOD GROUP SYSTEMCONNIE WESTHOFFThe Rh BLOOD GROUP SYSTEM is one of the mostpolymorphic and antigenic BLOOD GROUP sys-tems. It is second only to ABO in importance inblood transfusion and is well known as a primarycause of hemolytic disease of the fetus and newborn(HDFN). The principal antigen is D, and the termsRh positiveand Rh negativerefer to the presence orabsence of D antigen. Caucasians of European ex-traction have the highest incidence of the Rh-nega-tive phenotype (15% to 17%), and Rh-negative typeis much less common in Africa (5%) and Australiaand is considered a rare BLOOD type not routinelytested for in some parts of Asia ( 1%). Other com-mon Rh antigens include the antithetical C and c,and E and e antigens. Patients are not routinelytyped for these unless they have developed atypicalantibodies or are facing long-term transfusion sup-port for diseases such as myelodysplasia or sicklecell disease (SCD).

Ce r 37 26 3 Ce r 22 2 CE r 1 0.01 0.01 CE ry <0.01 0.01 0.01 version (Table 10-1) is useful in spoken language to convey the Rh haplotype. Uppercase R is used to de-scribe haplotypes that produce D antigen, and lower-case r (or little r) is used when D is absent. The C or c and E or e Rh antigens carried with D are represented by 1 for Ce (R

Loading..

Tags:

  System, Blood, Group, The rh blood group system, Ce r

Information