Immunodeficiencies Flashcards
What are the 2 types of immunodefiency disease?
Primary (congenital) immunodeficienies
Secondary Immuno deficiencies
What is primary immunodeficieny?
A condition resulting from a genetic or developmental defect abbreviated as PID
What is secondary immunodeficiency?
Originates from result of malnutrition, cancer drug treatment or infection
What is immunodeficiency?
Defects in one of more components of immune system leading to diseases
What is the most common cause of secondary immunodeficiency?
AIDS?
What causes PID?
Defect present from birth usually inherited
What are the clinical features of primary immunodeficiencies?
- Recurrent infections
- Severe infections of unusual pathogens in unusual sites
What are the 10 warning signs of PID?
copy past later
What part of the immune system does PID affect?
Can affect either innate or adaptive
Innate if defect causied by phagocytic or complement system
Adaptive if lymphoid cell disorders (affect B and T cells)
Can affeect both innate and adaptive = SEVER IMMUNODEFICIENCIES
What other condition to patients with immunodeficiences also present with and why?
Autoimmunity because cells that regulate own cells are not present
How does severity of PID change in diff individuals?
Depends which stage of haemotopoesis the defect is at, earlier on can affect entire immune system (more components and types involved)
- defects later of show less pathology
name a few adaptive immunodeficiencies?
XLA, selective IgA ID, SCID, DiGeorge, WAS
How are cells affected by PID in adaptive systems?
B cells, T cells or both
T cell defects impair antibody production
Defects in lymphocyte development and activation
Name a few major B cell PID disorders?
X linked agammaglobulinaemia (Bruton’s disease)
Selective IgA deficiency
What cause X linked agammaglobulinaemia (Bruton’s disease?
Defect in BTK gene - found on X chromosome
Why does mutation in BTK cause affect B cells in Bruton’s disease?
BTK codes for bruton’s tyrosine kinase without which there is a block in B cell development (halts at pre-B cell)
What are the effects/symptoms of Bruton’s disease?
Recuurent sever bacterial infections
2nd half of first year (affecting lung, ears, GI)
Autoimmine diseases in many patients
What are pre-B cells?
Bone marrow lymphoid cells that lack surface Igs but have intraplasmic regions of IgM heavy chains
How do you diagnose X linked agammaglobulinaemia?
B cells are absent / low despite and plasma cells completely absent
Immunoglobulin levels are low
T cells and T cell response all normal
- seen on flow cytometry
What is the treatment for X linked agammaglobulinaemia?
DO NOT GIVE LIVE ATTENTUATE VACCINES
Intravenous administration of exogenous antibodies
Prompt antibiotic therapy
What is IgA important for?
Important mucosal antibody
What is the presentation of selective IgA deficiency?
Most are asymptomatic but have infections of respiratory, urogenital ot gastrointestinal tract
Low levels of secretory IgA
Sometimes increased incidence of allergic disease