Flashcards in Immunology Deck (280)
What are the 4 hallmarks of immune deficiency?
what defines a serious infection?
unresponsive to oral antibiotics
what defines persistent infections?
early structural damage
what defines unusual infections?
what defines recurrent infections?
two major or one major + recurrent minor infections in one year
what 6 features apart from SPURS may be surggestive of primary immune deficiency?
weight loss/ failure to thrive
severe skin rash
unusual autoimmune disease
what 2 important infections lead to secondary immune deficiency?
what 3 important treatment interventions lead to secondary immune deficiency?
what type of malignancies can lead to secondary immune deficiency?
cancer of the immune system (lymphoma, myeloma, leukemia)
what biochemical/nutritional disorders can lead to secondary immune deficiency?
diabetes (Type 1 and 2)
what is a major feature of phagocyte deficiencies?
(which can affect either common or unusual sites)
what are the types of organisms typically infect patients with phagocyte deficiencies?
common bacteria (eg Staph sureus)
unusual bacteria (eg Burkholderia cepacia)
Mycobateria (TB and atypicals)
Fungi (candida, aspergillus)
what is the general life cycle of a phagocyte? (ie neutrophil
1. mobilisation of phagocytes and precursos from bone marrow or within tissues
2. upregulation of endothelial adhesion markers causing neutrophil adhesion and migration into tissues
3. phagocytosis and killing of organism
4. activation of other components of the immune system
what are the 2 reasons that can cause the failure of neutrophil production?
(and therefore neutropaenia and phacogyte deficiency)
failure of stem cells to differentiate along myeloid lineage
specific failure of neutrophil maturation
what is reticular dysgensis?
the failure of stem cells to differentiate along myeloid and lymphoid lineages. megakaryocyte-erythroid lineage is unaffected. most severe form of severe combined immunodeficiency (SCID)
when can the secondary defect which causes the failure of stem cells to differentiate along the myeloid lineage occur?
after stem cell transplantation
what are the 2 congenital causes of specific failure of neutrophil maturation? (and therefore cause neutropaenia)
what is Kostmanns syndrome?
rare autosomal recessive disorder causing the specific failure of neutrophil maturation- leads to severe chronic neutropaenia
what is Cyclic Neutropaenia?
episodic neutropaenia every 4-6 weeks caused by the specific failure of neutrophil maturation
when do patients with Kostmanns syndrome usually present with recurrent infections?
within 2 weeks after birth
what is the supportive treatment of Kostmanns syndrome?
what is the definitive treatment of Kostmanss syndrome?
stem cell transplantation
Granulocyte colony stimulating factor (G-CSF)
what is granulocyte colony stimulating factor (G-CSF)?
a growth factor which assists maturation of neutrophils
what rare, primary immunodeficiency is caused by the genetic defect in leukocyte integrins?
leukocyte adhesion deficiency
what does leukocyte adhesion deficiency result in?
failure of neutrophil adhesion and migration
what is the general clinical picture of leukocyte adhesion deficiency?
marked leukocytosis but with localised bacterial infections that are difficult to detect
what 2 receptors do phagocytes possess that bind to opsinons?
Fc receptors (for antibody Fc)
Complement receptor 1 (CR1- for binding to complement which are bound to the antigen)
what 2 defect can cause decreased efficiency of opsonisation? (and therefore a phagocyte deficiency)
defect of complement/antibody production
defect in opsonin receptor
what is chronic granulomatous disease?
a phagocyte deficiency due to failure of oxidative killing mechanisms