Primary Immunodeficiency - Pathoma Flashcards
SCID
severe COMBINED immunodeficiency: defective cell-mediated and humoral immunity
etiologies of SCID
- cytokine receptor defects (–> lack of cytokine signaling which is necessary for prolif and maturation of B and T cells)
- adenosine deaminase (ADA) deficiency –> buildup of adenosine and deoxyadenosine which are toxic to lymphocytes)
- MHC class II deficiency (needed for CD4+ helper T cell activation and cytokine production)
SCID treatment
sterile isolation; stem cell tcp
X-linked agammaglobulinemia
What is it?
Cause?
COMPLETE LACK of immunoglobulin (Ig) due to mutated Bruton tyrosine kinase –> disorder of B-cell maturation (naive B can’t mature to plasma cells so can’t get Ig in blood)
X-linked agammaglobulinemia presentation
- 6mo after birth (b/c have mom antibodies for 6mo after birth)
- recurrent bacterial, enterovirus, and Giardia infections
- don’t give live vaccines (ex: polio) !!
CVID
common variable immunodeficiency disease = LOW Ig due to B-cell OR helper T-cell defects
CVID presentation
- usually late in childhood - increased risk bacterial, enterovirus, and Giardia infections
- incr risk for autoimmune disease and lymphoma
IgA deficiency
- low serum and mucosal IgA
- most common Ig deficiency
- incr risk mucosal infections, especially viral
What deficiency is assoc w/ celiac disease?
IgA deficiency
Hyper IgM syndrome
elevated IgM
- due to mutated CD40L or CD40 receptor (2nd signal can’t be delivered to helper T cells during B-cell activation)
- cytokines needed for Ig class switching aren’t produced –> low IgA, IgG, and IgE –> recurrent pyogenic infections, esp at mucosal sites
Wiskott-Aldrich Syndrome presentation
- thrombcytopenia
- eczema
- recurrent infections (variety of them) - defective humoral and cellular immunity
Wiskott-Aldrich Syndrome genetics
WASP gene
- X-linked
Complement deficiency - Anything from C5-C9 puts at increase risk for —-
Neisseria infection
C1 inhibitor deficiency
hereditary angioedema characterized by edema of skin (esp periorbital) and mucosal surfaces
SCID presentation
- susceptibility to fungal, viral, bacterial, and protozoal infections including opportunistic infections and live vaccines
DiGeorge Syndrome
Developmental failure of 3rd and 4th pharyngeal pouches due to 22q11 microdeletion
DiGeorge Syndrome presentation
- T-cell deficiency (lack of thymus)
- hypocalcemia (lack of parathyroids)
- abnormalities of heart, great vessels, and face
