L21: Immunodeficiency Flashcards
What are immunodeficiency diseases
failure of the immune system
Primary ID
an individual is born with a genetic mutation that results in a defective immune response
Secondary ID
the individual is born with a normal immune response but experiences an event that damages the immune system.
how many primary ID are there
over 180
incidence of primary ID
1:5000 live births
what is the main clinical phenotype of 1° ID
increases suceptibilty to organisms that are of low pathogenicity in a healy person
explain the tree of immunodeficiency
primary and secondary - ID can occur in innate or adaptive IS
What are the defects in the innate immune system in primary immunodeficiency
- defects in:
- phagocyte response
- complement
What happens when there is a defect in the phagocyte repsonse (1ID)
defective phagocytes results in reccurent infections and fevers
what are the four types of phagocyte defects (1ID)
I. Deficiencies in production of phagocytes
II. Deficiencies in phagocyte adhesion
III. Deficiencies in phagocyte activation
IV. Deficiencies in phagocyte killing of microorganisms
What happens when there is leukocyte adhesion deficiencies
- integrin adhesion molecule defect (LFA1)
- absence of pus formation at the site of infeciton (no neutrophils)
- recurrent severe pyogenic bacterial and fungal infecitons with compromised wound healing
What is the purpose of LFA1
- adhesion molecule on outside of phagocyte → controls movement and trafficking of phagocytes along the endothelium
- Defect in protein - no trafficking - absence of pus (no neutrophils)
Chronic Granulomatous Disease
defect in phagocyte response - mutation of NADPH oxidase - cannot make ROS - failure to kill ingested bacteria
What happens when the classical pathway of the complement system is affected
no opsonisation by AB - clearance of infection reduced
what happens when there are defects in the C3 activation
deficiency leads to infection with pyogenic bacteria
