Q: Which equation best represents the relationship between HLA mismatches and kidney graft half-life, based on the CTS data?

$$\text{Half-life (years)} = 17.0 - 0.76 \times \text{Number of mismatches}$$

Question 1

A patient is being considered for a kidney transplant. The crossmatch test between the recipient's serum and the donor's cells is positive for IgG Class I antibodies. What is the most likely outcome if the transplant proceeds?

Accepted Answer

Hyperacute rejection within minutes to hours

Question 2

Which of the following best describes the structure of HLA Class I molecules?

Accepted Answer

Alpha chain (three domains: a1, a2, a3) plus beta2-microglobulin

Question 3

A laboratory is using Next Generation Sequencing (NGS) for HLA typing in haematopoietic stem cell transplantation (HSCT). What is the primary advantage of NGS over other methods?

Accepted Answer

It provides unambiguous phased allele assignment

Question 4

Which equation best represents the relationship between HLA mismatches and kidney graft half-life, based on the CTS data?

Accepted Answer

$$	ext{Half-life (years)} = 17.0 - 0.76 	imes 	ext{Number of mismatches}$$

Question 5

A patient with a history of multiple transfusions develops fever and rigors after receiving a blood product. Laboratory investigation reveals anti-HLA antibodies in the recipient. What is the most likely diagnosis?

Accepted Answer

Febrile Non-Haemolytic Transfusion Reaction (FNHTR)

Question 6

Which HLA typing method is most appropriate for rapid, low-ambiguity typing from any tissue and does NOT require live cells?

Accepted Answer

PCR-SSP

Question 7

In the context of HLA nomenclature, what does the suffix 'N' indicate in an allele such as HLA-A*02:01:01:02N?

Accepted Answer

Null allele; not expressed on the cell surface

Question 8

A patient is prescribed abacavir for HIV treatment. Which HLA allele must be screened to prevent severe hypersensitivity reactions?

Accepted Answer

HLA-B*57:01

Question 9

Which of the following best explains the mechanism of TRALI (Transfusion-Related Acute Lung Injury)?

Accepted Answer

Donor anti-HLA or anti-HNA antibodies react with recipient leucocyte antigens

Question 10

Which intervention is used to prevent TaGVHD in transfusion recipients at risk?

Accepted Answer

Gamma irradiation of cellular blood products

Question 11

A patient with coeliac disease is found to carry HLA-DQA1*05 and DQB1*02 alleles. What is the relative risk (RR) of coeliac disease associated with this HLA type?

Accepted Answer

$$RR \u003e 250$$

Question 12

Which of the following is TRUE regarding HLA Class II molecules?

Accepted Answer

They present peptides to CD4+ T helper cells

Question 13

A patient with Type 1 Diabetes is found to carry HLA-DQB1*06:02. What is the significance of this allele?

Accepted Answer

It is protective against Type 1 Diabetes

Question 14

Which of the following best describes the concept of 'haplotype' in HLA genetics?

Accepted Answer

A complete set of HLA alleles (A+B+C+DR+DQ+DP) inherited en bloc from one parent

Question 15

In the Luminex SAB assay, what does a high Mean Fluorescence Intensity (MFI) indicate?

Accepted Answer

Strong antibody binding to a specific HLA antigen

Question 16

A patient with ankylosing spondylitis is most likely to carry which HLA allele?

Accepted Answer

HLA-B*27

Question 17

Which of the following is the most common immunological cause of platelet refractoriness?

Accepted Answer

Anti-HLA Class I antibodies

Question 18

In flow cytometry crossmatch, which fluorochrome-conjugated antibody is used to identify T cells?

Accepted Answer

Anti-CD3/PE

Question 19

Which of the following statements about HLA inheritance is correct?

Accepted Answer

Both parental HLA alleles are expressed (co-dominant inheritance)

Question 20

A patient with multiple sclerosis is most likely to carry which HLA alleles?

Accepted Answer

HLA-DRB1*15 and DQB1*06

HLA in Transplantation and Transfusion: Comprehensive Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards