Question 1

A type-A person demonstrates a 3+ reactivity with A₁ cells (reverse grouping). The forward grouping with anti-A is 4+. Therefore, the possibility of a subgroup is excluded. B cells demonstrate a 4+ reaction. The antibody screen is weakly positive at 37°C but shows no reactivity at the AHG phase. An antibody panel is performed and anti-M is identified. The patient phenotypes negative for M antigen. How is the ABO discrepancy resolved?

Accepted Answer

The discrepancy is due to the presence of anti-M, which reacts at room temperature. Using A1 cells negative for M antigen in reverse grouping will resolve the discrepancy.

Question 2

If a type-A person contains anti-M in his or her serum, what might the reverse grouping type as?

Accepted Answer

A type-A person with anti-M in their serum may have a reverse grouping type as O, as the presence of anti-M suggests the absence of M antigens, which are typically found in type A and B blood.

Question 3

All of the following are technical errors that could result in ABO discrepancies except:

Accepted Answer

Failure to warm reagents is not typically associated with ABO discrepancies, as ABO testing does not generally require warming of reagents.

Question 4

Which ABO group's reaction will be the weakest with anti-H lectin?

Accepted Answer

AB group individuals have the least amount of H antigen, leading to the weakest reaction with anti-H lectin.

Question 5

What is the cause of polyagglutination in most cases?

Accepted Answer

Polyagglutination is often caused by the exposure of T antigen on red blood cells due to bacterial contamination, which alters the red blood cell surface and leads to agglutination by most human sera.

Question 6

What is the source of anti-B lectin?

Accepted Answer

Bandeiraea simplicifolia is the source of anti-B lectin, which is used to identify B antigens in blood typing.

Question 7

Why is reverse grouping not performed on cord blood specimens?

Accepted Answer

Reverse grouping is not performed on cord blood specimens because antibodies, particularly the naturally occurring ones used in reverse grouping, are generally not present at birth. Newborns have not yet developed their own antibodies, and any antibodies present are typically maternal IgG antibodies that have crossed the placenta.

Question 8

Two drops of serum are added to one drop of A₁ cells, and two drops are added to one drop of B cells; the two tubes are centrifuged. The tubes show reactivity when read macroscopically. This is an example of:

Accepted Answer

Reverse grouping involves testing the patient's serum with known A and B cells to determine the presence of anti-A or anti-B antibodies.

Question 9

If a group O mother gives birth to a group A baby, which of the following antibodies is usually responsible for crossing the placenta and causing hemolytic disease of the newborn (HDN)?

Accepted Answer

The answer of If a group O mother gives birth...

Question 10

What percentage of the type A population is A₂?

Accepted Answer

The question asks for the percentage of the type A population that is A2, which is given as 20%.

Question 11

An elderly patient is documented as being type O. The forward grouping is negative with anti-A and anti-B. The reverse grouping shows no reactivity with A₁ cells and B cells. What can be done to correct the discrepancy?

Accepted Answer

The discrepancy between the forward and reverse grouping suggests that the patient's serum contains an antibody that is not reacting with the reagent cells. Incubating the patient's serum and reagent cells for 15 minutes at room temperature will allow the antibody to react with the reagent cells and correct the discrepancy.

Question 12

All of the following is true regarding formation of the ABH antigens except:

Accepted Answer

Type 1 structures refer to a beta 1-3 linkage, not beta 1-2.

Question 13

When performing secretor studies, what is omitted in the control tube but present in the patient tube?

Accepted Answer

In secretor studies, saliva is present in the patient tube to test for the presence of soluble blood group substances, but it is omitted in the control tube to serve as a baseline comparison.

Question 14

What is used to stimulate saliva secretion in secretor studies?

Accepted Answer

Paraffin wax is commonly used to stimulate saliva secretion in secretor studies because it encourages chewing without being ingested, thus promoting saliva production.

Question 15

The ABO group antibodies are primarily:

Accepted Answer

The answer of The ABO group antibodies are primarily:
...

Question 16

What percentage of the white population has type-O blood?

Accepted Answer

Approximately 45% of the white population has type-O blood.

Question 17

Reverse grouping showed negative reactions with A₁ and B cells. Forward grouping showed positive reactions with A, B, and AB antisera. What blood type is consistent with these results?

Accepted Answer

Forward grouping showed positive reactions with A, B, and AB antisera. This indicates that the blood contains both A and B antigens. Reverse grouping showed negative reactions with A1 and B cells. This indicates that the blood does not contain anti-A or anti-B antibodies. Therefore, the blood type is AB.

Question 18

What immunodominant sugar is responsible for H specificity?

Accepted Answer

L-fucose is the immunodominant sugar responsible for H specificity in the ABO blood group system.

Question 19

All of the following statements are true concerning ABH soluble substances except:

Accepted Answer

The answer of All of the following statements are true...

Question 20

Mixed-field agglutination encountered in ABO forward grouping may be caused by:

Accepted Answer

The answer of Mixed-field agglutination encountered in ABO forward grouping...

Quiz 6: The Abo Blood Group System

If a type-A person contains anti-M in his or her serum, what might the reverse grouping type as?

All of the following are technical errors that could result in ABO discrepancies except:

Which ABO group's reaction will be the weakest with anti-H lectin?

What is the cause of polyagglutination in most cases?

What is the source of anti-B lectin?

Why is reverse grouping not performed on cord blood specimens?

Two drops of serum are added to one drop of A₁ cells, and two drops are added to one drop of B cells; the two tubes are centrifuged. The tubes show reactivity when read macroscopically. This is an example of:

If a group O mother gives birth to a group A baby, which of the following antibodies is usually responsible for crossing the placenta and causing hemolytic disease of the newborn (HDN) ?

What percentage of the type A population is A₂?

An elderly patient is documented as being type O. The forward grouping is negative with anti-A and anti-B. The reverse grouping shows no reactivity with A₁ cells and B cells. What can be done to correct the discrepancy?

All of the following is true regarding formation of the ABH antigens except:

When performing secretor studies, what is omitted in the control tube but present in the patient tube?

What is used to stimulate saliva secretion in secretor studies?

The ABO group antibodies are primarily:

What percentage of the white population has type-O blood?

Reverse grouping showed negative reactions with A₁ and B cells. Forward grouping showed positive reactions with A, B, and AB antisera. What blood type is consistent with these results?

What immunodominant sugar is responsible for H specificity?

All of the following statements are true concerning ABH soluble substances except:

Mixed-field agglutination encountered in ABO forward grouping may be caused by:

Quiz 6: The Abo Blood Group System

If a type-A person contains anti-M in his or her serum, what might the reverse grouping type as?

All of the following are technical errors that could result in ABO discrepancies except:

Which ABO group's reaction will be the weakest with anti-H lectin?

What is the cause of polyagglutination in most cases?

What is the source of anti-B lectin?

Why is reverse grouping not performed on cord blood specimens?

Two drops of serum are added to one drop of A1 cells, and two drops are added to one drop of B cells; the two tubes are centrifuged. The tubes show reactivity when read macroscopically. This is an example of:

If a group O mother gives birth to a group A baby, which of the following antibodies is usually responsible for crossing the placenta and causing hemolytic disease of the newborn (HDN) ?

What percentage of the type A population is A2?

An elderly patient is documented as being type O. The forward grouping is negative with anti-A and anti-B. The reverse grouping shows no reactivity with A1 cells and B cells. What can be done to correct the discrepancy?

All of the following is true regarding formation of the ABH antigens except:

When performing secretor studies, what is omitted in the control tube but present in the patient tube?

What is used to stimulate saliva secretion in secretor studies?

The ABO group antibodies are primarily:

What percentage of the white population has type-O blood?

Reverse grouping showed negative reactions with A1 and B cells. Forward grouping showed positive reactions with A, B, and AB antisera. What blood type is consistent with these results?

What immunodominant sugar is responsible for H specificity?

All of the following statements are true concerning ABH soluble substances except:

Mixed-field agglutination encountered in ABO forward grouping may be caused by:

Two drops of serum are added to one drop of A₁ cells, and two drops are added to one drop of B cells; the two tubes are centrifuged. The tubes show reactivity when read macroscopically. This is an example of:

What percentage of the type A population is A₂?

An elderly patient is documented as being type O. The forward grouping is negative with anti-A and anti-B. The reverse grouping shows no reactivity with A₁ cells and B cells. What can be done to correct the discrepancy?

Reverse grouping showed negative reactions with A₁ and B cells. Forward grouping showed positive reactions with A, B, and AB antisera. What blood type is consistent with these results?