Inborn Errors of Immunity Flashcards
What does the innate vs adaptive immune system detect? What are the receptors of the two divisions?
- Innate detects PAMPs, and DAMPs (WAT?)
- Adaptive detects a huge range of specific antigens
- Innate uses PRRs (WAT?)
- Adaptive uses TCRs and Ig on surface of B cells
What are inborn errors of immunity (including the exact kind of change(s) that cause them)? What do they predispose to?
- IEI are genetically determined, inborn errors of immunity
- They can be widely heterogeneous, and can have variable clinical phenotype
- They predispose to recurrent/unusual infections, as well as increased risk of malignancy/immune regulation (interesting that these two link together)
What are some possible warning signs of primary immunodeficiency?
- Need for IV antibiotics to clear infections
- Persistent thrush/fungal infection (what else causes thrush? why?)
- FHx
- Multiple serious sinus infections in one year
Why is early and accurate diagnosis of inborn errors of immunity so important?
- Early intervention can prevent recurrent infections and irreversible end organ damage
- Early diagnosis allows for best possible planning of interventions and long-term plans, such as vaccination strategies
- Can also allow for genetic screening in other family members who may have inherited the disorder(s) moving forward
What kinds of infections are more likely in someone with phagocyte/complement/humoral/cellular immunodeficiency?
- Phagocyte: bacteria/fungal
- Complement: bacteria
- Humoral: bacteria (+ some viruses)
- Cellular: all
Outline three types of tests that can be used to diagnose inborn errors of immunity. Are these broadly similar for each patient as part of the immunodeficiency screen?
- Genetic testing: DNA is extracted/sequenced from a sample of tissue, and assessed for abnormalities
- Immunological assays: assess the number and function of cells, levels of Ig, cytokines etc.
- Clinical: Hx (?recurrent infections, ?autoimmunity, ?Fhx, ?recurrent miscarriages)
Outline the 4 broad categories of treatment for inborn errors of immunity
- Preventitive (immunisation, screening, prophylactic Rx)
- Supportive (IvIg, Plasmapheresis)
- Targeted (enzyme replacement, immunosuppressive biologics)
- Curative (stem cell transplant, thymus transplant)