Blood Bank CLT Exam Review

What is the basic technique employed to detect antibodies with a commercial set of panel cells?

Indirect antiglobulin test

Avidity is best described as:

The strength with which multivalent antigens and antibodies bind.

True/False. RhIg for IM use may cause a reaction if administered intravenously.

True

A technologist performing an antibody identification in the blood bank has recorded the following results found in the worksheet below. Which antibody(ies) are MOST LIKELY the cause of the agglutination reactions in this patient's sample?

anti-Jka, anti-E

Which Rh antigen is found the highest frequency in the Caucasian population?

e

True/False. At least three antigen-positive red cells that react and three antigen-negative cells that do not react are required to identify an antibody with acceptable statistical significance despite how many cells are included in the panel.

False

True/False. For infants born to Rh negative females, a test for weak D is optional when initial D typing shows the newborn to be Rh negative.

False

Which of the following donors could be accepted for blood donation? 22-year female currently pregnant 40-year-old female lived in London from 1988 - 1992 44-year-old male taking aspirin every four hours for the past two days 24-year-old man who had a tooth extraction two months ago

24-year-old man with a tooth extraction two months ago

How many out of 1,000,000 Caucasians will have the following phenotype: Group 0, K+, Jk(a+)?

30,000

Which steps should be taken in the IMMEDIATE investigation of a potential hemolytic transfusion reaction?

ABO and DAT on the post-transfusion patient sample Check for a clerical error Visual examination of the post-reaction and pre-reaction (if available) plasma for hemolysis

Which tess must be repeated by the lab on homologous blood received from the Red Cross or other community blood sources?

ABO and Rh

At what phase of antibody screen testing is it most important to read the reactions in order to detect clinically significant antibodies?

AHG

Which of the following best describes the primary function of antibodies?

Bind with antigen

Red blood cells with a positive DAT cannot be tested accurately with blood typing reagents that require an indirect antiglobulin technique unless they have been treated with ___________________ to dissociate IgG from the RBC membrane.

Chloroquine diphosphate, Ficin, or ZZAP

Which procedure used to obtain a fetal blood sample to monitor severity of HDFN can also be used to deliver intravenous transfusions?

Cordocentesis

Which Lewis blood group system phenotype usually produces anti-Lea?

Le(a-b-)

Which blood group antigen is not expressed, or only weakly expressed on cord blood cells?

Le(b)

Which serological test results may occur in a patient experiencing a hemolytic transfusion reaction due to antibodies such as anti-c and anti-K?

Patient's antibody strength may initially decrease. Patient may develop a positive DAT with mixed-field agglutination. Patient's antibody becomes undetectable. Patient's antibody increases in titer weeks later.