The immunogenicity of the common Rh antigens may be describe

The immunogenicity of the common Rh antigens may be described from greatest to least as:

D>c>E>C>e

c>D>C>E>e

D>c>E>e>C

D>C>E>c>e

How many units would you have to type to obtain two compatible units for a patient with an anti-K, anti-Fya and anti-E?

15 units

50 units

10 units

2 units

20 units

Which of the following statements is false?

Rh antibodies do not bind complement.

Rh antibody cell destruction is intravascular.

Most Rh antibodies persist for many years.

Rh antibodies may cause haemolytic disease of the new born.

Rh antibodies may be any one of the four IgG subclasses, and those in subsclasses IgG1 and IgG3 being far more destructive.

With respect to the Kell blood group system, which of the following statements is false?

Kell system antibodies are unlikely to be present in a serum reactive to most if not all cells initially tested (auto negative).

Weakened expression of the Kell system antigens is called the McLeod phenotype, and is characterised by morphological and functional red cell defects.

The Kell blood group system includes several low- and high- frequency antigens, and includes a total of at least 21 antigens.

Anti-K is an important cause of HDN.

The major difference between the Weiner theory and Fisher-Race is that Weiner postulates that the genetic inheritance is described as:

Three loci and three genes inherited linked together.

A single locus, with 8 different allelic genes.

A numerical system without any implications of genetic linkages.

There are two closely related and closely linked genes.

What ABH substances would be found in the saliva of a group B secretor?

H and A.

H.

H, A, and B.

H and B.

Solution

1. Answer Option D - DCEce. Because the antigen D predominant followed by C E c and e.

2. In case of more than one antibody the % compatibility has to be multiplied. In this case it is  anti-K - 91%, anti-Fya - 70% and anti-E - 70%

Hence compatible units = 91% x 70% x 70% = 44.5% = 50 Units.

No of units required/ percentage compatible = 2/44.5% = 4.5

Answer - Option 3 - 10 Units - This is the nearest ones.

3. Answer - Option A - The Rh antibodies binds to complement. All other statements are true

4. Answer - Option A - Kell system antibodies are unlikely to be present in a serum reactive to most if not all cells initially tested (auto negative) is false.

5. The major difference between the Weiner theory and Fisher-Race is that Weiner postulates that the genetic inheritance is described as: Answer - Option B - A single locus, with 8 different allelic genes.

6. Answer - Option C - H, A and B.