Medical Laboratory Science Review - Blood Bank

Flashcards for Medical Laboratory Science topics in Blood Bank focusing on essential concepts, facts, and procedures.

What type of testing is routinely performed in the blood bank to determine a patient's blood group?

Phenotyping, which is the physical expression of a genotype.

What does a stronger reaction of an antibody with homozygous cells than with heterozygous cells indicate?

Dosage.

Why does dosage effect occur with antibodies like anti-K?

Because antibodies react stronger with homozygous (e.g., KK) cells than with heterozygous (e.g., Kk) cells.

What factors may account for the absence of certain blood group antigens in individuals?

Gender and race.

What is the expected DNA complement of gametes produced during meiosis?

1N.

What stage is a cell in when it is not actively dividing?

Interphase.

What describes the inheritance of most blood group antigens?

Codominant.

If a patient has AO and the partner has BO, what blood type can they not have?

AB.

What type of exclusion occurs if the alleged father is AB and the child is O?

Indirect or secondary exclusion.

If two genes Y and Z have frequencies of 0.4 and 0.5 respectively but are found together 32% of the time, what is this an example of?

Linkage disequilibrium.

In the Hardy-Weinberg formula, what does p2 represent?

The homozygous population of one allele.

What type of inheritance is characterized by all daughters expressing the trait if a father carries it on his X chromosome?

X-linked dominant.

What is the reason IgM antibodies can agglutinate red blood cells?

IgM antibodies are larger and can bind more antigens.

What enhancement medium decreases the zeta potential to improve antigen-antibody interaction?

LISS (Low Ionic Strength Saline).

What type of response is an anamnestic response?

A secondary immune response in which memory lymphocytes rapidly respond to a foreign antigen.

What antibodies are contained in the rabbit polyspecific antihuman globulin reagent?

Anti-IgG and anti-C3d.

How can you distinguish between A1 and A2 blood groups?

An A2 person may form anti-A1 while an A1 person will not.

Why is the Bombay phenotype incompatible with type O blood cells?

Bombay individuals do not express H antigen, which type O blood contains.

What antibodies are formed by a Bombay individual?

Anti-A, anti-B, and anti-H.

What is the expected action if all forward and reverse ABO results are positive?

Wash the cells with warm saline.

What should be done if all forward and reverse ABO results are negative?

Perform additional testing such as typing with anti-A1 lectin and anti-A,B.

What immunodominant sugar reacts with Dolichos biflorus lectin?

N-acetyl-D-galactosamine.

What could a 4+ reaction with anti-A and negative reaction with A1 cells indicate?

The patient may have acquired B antigen.

What blood group has the least amount of H antigen?

A1B.

What should be done for a patient with a positive direct antiglobulin test (DAT)?

Perform weak D testing on the cells is not necessary.

Which genotype would an individual with anti-C likely possess?

rr (dce/dce).

What should be done if a positive DAT indicates antibody coating the patient cells?

Perform an elution followed by a cell panel on the eluate.

What indicates the need for washing cells supports the presence of a cold agglutinin?

Clear RBCs after washing should yield negative reactions.

What is the effect of anti-M presence on crossmatching?

It may cause incompatibility reactions.

What is the best way to remove a clinically insignificant antibody?

Adsorption techniques.

What is the main concern with a titer of anti-M reacting strongly across all phases?

It may hinder the detection of clinically significant antibodies.

How can the specificity of an unknown antibody suspected to be anti-Jka be verified?

Use a select panel of homozygous cells.

What course of action should follow the detection of complement-dependent antibodies?

Perform a salicylate replacement on the cells.

What would not contribute to revealing a clinically significant antibody if a high titer antibody is present?

Lowering the pH.

How can a blood product with a clotted sample be handled?

Do not issue the unit.

What definition applies to granulocyte concentrates?

Crossmatching with recipient serum is required.

Why would a leukoreduced red cell unit indicate compatible blood?

They have clinical aqueous for use.

What is the expected outcome for an HLA type platelets transfusion?

PT screens negative.

What method is effective in neutralizing anti-Lea?

Use of saliva from an Le(a-b-) individual.

How do antibodies against low-incidence antigens affect transfusion?

May require identifying rare blood groups.

What is typically expected after transfusion in patients receiving blood products?

Monitoring for febrile reactions.

What are antibodies involved in hemolytic disease of newborn?

Maternal antibodies against fetal RBC antigens.

What is the most common cause of false positive in crossmatch testing?

Technical errors.

What factors influence the probability of successfully using parts from blood transfusions?

Timing, testing techniques, and unit storage.

How should discrepancies in blood bank results be handled?

Further verification tests should be conducted.

What action is necessary when a red blood cell unit is found leaking?

Discard the unit.