Overview Of Major Antigens of the Rh Blood Group System
Continuing Education Credits
This course aims to provide the learner with an overview of the Rh blood group system, to review the unique characteristics of the antigens and antibodies of the system, to describe the naming conventions associated with the system, and to stimulate an appreciation for the complexities of the Rh system. The content provided is written with the assumption that the learner has a basic understanding of immunohematology and the ABO blood group system prior to taking this course.
Objectives
- Recall the five major antigens of the Rh blood group system.
- Describe and compare several nomenclature conventions commonly used when discussing the Rh blood group system.
- List the characteristics of the Rh blood group system, including basic biochemical and molecular composition as well as chromosome location and inheritance.
- Describe four mechanisms that may result in weakened expression of the D antigen.
- List characteristics of antibodies commonly encountered in the Rh blood group system, phase of reactivity, ability to cross the placenta, and effect of enzyme treatment during testing.
Course Outline
- Overview of Rh
- Introduction to the Rh System
- History of Rh and Association with LW
- Rh typing is considered extremely important in pre-transfusion testing because:
- The antibody that reacts with most D-positive red blood cells (RBCs), weakly with D-negative RBCs, and never with Rhnull RBCs is:
- Genetics/Biochemistry
- Genes of the Rh System
- Biochemical and Functional Characteristics of Rh
- Nomenclature and Inheritance in the Rh System
- Terminology
- Fisher-Race DCE Terminology
- Haplotype Prevalence in Fisher-Race Terminology
- Wiener Rh-Hr Terminology
- Fisher-Race and Wiener Terminology Roadmap
- Rosenfield Alphanumeric Terminology
- ISBT Numeric Terminology
- Which of the following is not a terminology used for the Rh blood group system?
- Using Rosenfield terminology and the possible answers below, select the correct way to write the phenotype for a red cell sample that reacts as follows:D+ (C negative) E+ (c not tested) e+
- Match the correct Wiener shorthand with the Fisher-Race designation provided.
- Based on the reactions below, what is the only possible Fisher-Race designation for this patient?D +C +E negc +e +
- Rh System Antigens and Important Genetic Alterations
- Rh Antigens of Clinical Importance
- Alterations in D Antigen Expression
- Four Mechanisms of Weakened Expression of the D Antigen
- Mechanism 1: C in trans to RHD
- Mechanism 2: Weak D
- Mechanism 3: Partial D
- Mechanism 4: Del
- Deletion, Null, and Mod Phenotypes in the Rh System
- Inheritance of the Rhnull and Rhmod Phenotypes
- Other Unusual Phenotypes and Rare Alleles in the Rh System
- Which item below does not represent a mechanism that will result in the weakened expression of the D antigen?
- From the list below, select the item that does not represent null or deletion phenotypes.
- Characteristics of Rh System Antibodies
- Characteristics of Rh Antibodies
- Screening the Intended Recipient for Alloantibodies, Including the Rh System
- Laboratory Testing for Rh System Antigens and Antibodies
- Reagents for Use in Rh Typing
- False-Positive Reactions with Rh Typing Reagents
- False-Negative Reactions with Rh Typing Reagents
- Rh Testing for Blood Donors and Labeling Blood Products
- Reagents manufactured from a single clone of antibody-producing cells are called:
- Which of the following situations can result in a false-negative reaction with Rh typing reagents?
- Clinical Considerations Related to the Rh System
- Hemolytic Disease of the Fetus and Newborn
- Hemolytic Transfusion Reaction
- Special Considerations for Chronically or Multiply Transfused Patients
- From the choices below, all are reasons that Rh antibodies are clinically significant except:
- A common practice for preparing red blood cell products for chronically transfused patients is to match the Rh phenotype of the recipient and donor by testing both for the common Rh and K antigens. What is the best rationale for this practice?
- Case Study
- Rh Case Study
- Discussion of Rh Case Study
- Rh Case Study, Further Testing
- Rh Case Study, ID Panel Cross-out
- Further Discussion of Rh Case Study
- References
- References
Additional Information
Level of Instruction: Intermediate
Intended Audience: Medical laboratory scientists, medical laboratory technicians, laboratory supervisors, and laboratory managers. This course is also appropriate for MLS and MLT students and pathology residents.
Author Information: Pamela Inglish, MLS(ASCP)SBB, has 30+ years of experience in medical laboratory sciences, having completed training at the Medical College of Virginia/Virginia Commonwealth University. Subsequently, she obtained certification as a Specialist in Blood Banking through AABB/ASCP. For the majority of her career, Ms. Inglish held positions of responsibility in hospital transfusion services, blood centers, and clinical stem cell transplant processing laboratories, and has also sold clinical lab diagnostic equipment and reagents. In her most recent position at the University of Cincinnati/Hoxworth Blood Center, she was director of quality assurance and education and served as an adjunct instructor.
The author has no
conflict of interest to disclose.
Reviewer Information:
Laurie Bjerklie, MA, MLS(ASCP)CM, is
a Lead Education Developer. She earned a B.S. in Medical Laboratory Science
from the University of North Dakota and an M.A. in Curriculum and Instruction
from Saint Xavier University. She has over 15 years of experience in higher
education and has held program director and faculty positions in both MLT and
MLS programs.
Kaitlin Faughnan, MS, MLS(ASCP)CM, is currently a faculty member of SUNY Broome Community College, where she teaches all subjects of MLS to both Medical Laboratory Technician and Histotechnician students. She is involved in curriculum development and revision, as well as researching updates to the field of laboratory science to stay on the cutting edge of the latest information and technology. She received both her Bachelor of Science and Master of Science in Clinical Laboratory Science. She holds New York state licensure and previously worked as a generalist in a hospital.