Immunodeficiency And Autoimmune Disorders Flashcards
Developmental failure of 3rd and 4th pharyngeal pouch due to 22q11 microdeletion
DiGeorge Syndrome
Clinical presentations of DiGeorge Syndrome
T cell deficiency (no thymus)
Hypocalcemia (no parathyroid)
Heart, great vessel, and face abnormality
Defective cell mediated and humoral immunity
Severe combined immunodeficiency (SCID)
Etiologies of SCID
Cytokine receptor defect - no binding to helper T cell Adenosine deaminase deficiency - salvage pathway. Accumulation is toxic to lymphocytes MHC class II deficiency
Treatment for SCID
Sterile.isolation
Stem cell transplant - to generate normal B and T cells
Lack of immunoglobulin due to B cell maturation disorder, naive B cells cannot be plasma cells
X linked agammaglobulinemia
Mutation involved in X linked agammaglobulinemia
Bruton tyrosine kinase (signal molecule defect)
Presentation of X linked agammaglobulinemia
Recurrrent bacterial, enterovirus, and giardia infections after 6 months when no more maternal antibodies
Low immunoglobulin duento B cell or helper T cell defect
Common Variable Immunodeficiency
Presentation of CVID
Increased risk for bacterial enterovirus and giardia infection late in childhood, increase risk fot autoimmune disease and lymphoma
Most common immunoglobulin deficiency
IgA deficiency
Presentation of IgA deficiency
Increased risk of mucosal infection, mostly viral
Pathophysiology of Hyper IgM syndrome
Secondary signal for B cell maturation in the CD40 is defective, so helper t cell is not activated and no class switching is possible.
But B cells can still be activated by antigens so IgM production continues
Presents with a triad of thrombocytopenia, eczema, and recurrent infections, due to x linked gene defect
Wiskott-Aldrich Syndrome
C5 to C9 deficiency is at risk for what infection
Neisseria
Complement deficiency characterized by hereditary angioedema
C1 inhibitor defiency (uncontrolled vasodilation)
Mechanism of hypersensivity of SLE
Type II - binding of antibody to cells
Type III - antigen antibody xomplex
Most common glomerular injury in SLE
Diffuse proliferative Glomerulonephritis
Pathology of Libman Sacks endocarditis
Vegetations on both sides of valve from dposition of antibodies
Most common antibodies in APAS
Anticardiolipin and lupus anticoagulant
Anticardiolipin and lupus anticoagulant lead to erroneous results of which lab results
Anticardiolipin - false positive syphilis test
Lupus anticoagulant - falsely elevated PTT
Autoimmune disorder which destroyes lacrimal and salivary glands causing fibrosis
Sjogren Syndrome
Sjogren syndrome is what type of hypersensitivity reaction
Type IV
Antibodies found in Sjogren syndrome
Anti ribonucleoprotein antibodies (anti SS-A and anti SS B)
Sjogren syndrome patients are at increased risk for which malignancy
B cell lymphoma (unilateral enlargement of parotid)
Autoimmune disorder with activation of fibroblasts and deposition of collagen (fibrosis)
Scleroderma
Most commonly involved organ in diffuse scleroderma
Esophagus
Antibodies in Scleroderma
Anti DNA topoisomerase I (Scl-70)
Clinical manifestations of localized scleroderma
Calcinosis/anti Centromere antibodies Raynaud phenomenon Esophageal dysmotility Sclerodactyly Telangiectasias of skin
Antibodies for mixed connective tissue disease
Anti U1 ribonucleoprotein
