Immunodeficiency Flashcards Preview

Clinical Pathology > Immunodeficiency > Flashcards

Flashcards in Immunodeficiency Deck (24):
1

Name 3 mechanisms by which antibodies bind to antigens to enhance phagocytosis

Neutralisation
Agglutination
Precipitation

2

Name the mechanism direceted by antibodies that enables cell lysis

Activation of complement system

3

How to cytotoxic T cells act?

Bind to infected cells and perforin makes holes in infected cell's membrane and enzyme enters. Infected cell is destroyed.

4

What are the cytokines released by innate cells that direct the immune system to carry out more appropriate response

Pathogen associated molecular patterns (PAMP) e.g. directs T cells to develop into Th1, Th2 or Treg

5

Primary immunodeficiencies

Genetic defect in component of immune system

6

Secondary immunodeficiencies

Secondary to the effects of external factors

7

IRAK4 deficiency -PRR activation defect

TLRs become activated and trigger a cascade of cytokine release- IRAK is essential in the production of an inflmmatory response- as adaptive immune system develops, other pathways offer protection-most severe in early life.

8

Chronic granulomatous disease

Defect in phagocytosis affecting primarily males. AR. Neutrophils are unable activate proteolytic enzymes in phagosome. Defect in NADPH-oxidase complex-transports H+ across phagosome membrane.

9

Diagnosis of chronic granulomatous disease

Nitroblue tetrazolium test- normally neutrophils release oxygen radicals which converts blue dye to black. Defect = no chance in colour

10

Clinical presentation of CGD

Osteomyelitis, pneumonia, swollen lymph nodes, ginigivitis-gum disease, non malignant granuloma, inflammatory bowel disease

11

Which complement pathways activate C5 to form pores in bacterial cell wall?

All 3

12

Diagnosis of complement deficiency

Sheep RBCs incubated in patient's serum-in competent terminal pathway- lysis of RBCs.

13

Clinical presentation of complement deficiency

Meningococcal infections

14

Treatment for people with complement deficiencies

Vaccines for meningococcal e.g. penicillin prophylaxis

15

X linked agammaglobinaemia

Defect in B cells- antibody deficiency. Recurrent bacterial infections e.g. sino pulmonary infections. Usually diagnosed 1-2 yr, since maternal IgG protects.

16

Treatment for X linked agammaglobinaemia

Treat with antibodies, then IgG for life

17

Sever combined immunodeficiency (SCID)

Absent/reduced T cells and reduced B cells. Usually more severe than B cell defects, as B cells also need T cell help.

18

Clinical presentation of SCID

Recurrent infections with opportunistic infections

19

Treatment for SCID

Bone marrow transplant, gene therapy

20

Infections caused in PRR activation defects

Pneumococcus, HSV

21

Infections caused in phagocyte defects

CGD, staphylococcus aspergicillus

22

Infections caused in complement defects

Meningococcus

23

Infections caused in B cell defects

Recurrent sino-pulmonary infections

24

Infections caused in T cell defects

SCID, opportunistic infections