Immunodeficiency disorders Flashcards
For DiGeorge Syndrome, what is this due to? What are some presentations?
- developmental failure of the third and fourth pharyngeal pouches (22q11 microdeletion)
- T-cell deficiency (lack of thymus), hypocalcemia (lack of parathyroids), abnormalities of heart, great vessels, face
Severe combined immunodeficiency (SCID): what is it, etiologies, characterized by, treatment
- defective cell-mediated and humoral immunity
- cytokine receptor defects (need cytokine signaling for mature B and T cell proliferation),
ADA deficiency (needed to deaminate adenosine and deoxyadenosine for excretion as waste products; buildup is toxic to lymphocytes),
MHC class II deficiency - susceptibility to fungal, viral, bacterial, and protozoal infections, including opportunistic infections and live vaccines
- sterile isolation (‘bubble baby’) and stem cell transplantation
We didn’t know this but the inside linebacker, number 7, had some CRazy defect, and it ended up affecting our Backs and Tackles. Later, our assistant dean of admissions took ill with something also. Then, my head coach just fell apart. As it turned out, I should have learned they should not Fuck Very Big Pussy, or we get prone to opportunistic infections and live vaccines. Now these kids are as bad as that kid in a bubble and might need a transplant.
X-linked agammaglobulinemia: what does it involve, cause, presentation, what to avoid?
- complete lack of immunoglobulin due to disordered B-CELL MATURATION (pre- and pro-B cells can’t mature)
- mutated Bruton tyrosine kinase; X-linked
- presents after 6 months of life with recurrent bacterial, enterovirus (e.g. polio and coksackievirus), and Giardia lamblia infections; maternal Abs present during first 6 months of life are protective
- AVOID LIVE VACCINES
Common variable immunodeficiency (CVID): involves what, risk for what?
- low immunoglobulin due to B-cell or helper T-cell defects
- Increased risk for bacterial, enterovirus, and Giardia lamblia infections, usually in late childhood; also for autoimmune disease and lymphoma
IgA deficiency: what is this and what are you at increased risk for?
- low serum and mucosal IgA; most common immunoglobulin deficiency
- increased risk for mucosal infection, especially viral; however, most patients are asymptomatic!!
Hyper-IgM syndrome: characterized by, due to what? misc
- Elevated IgM
- mutated CD40L (on helper T cells) or CD40 receptor (on B cells): no second signal delivery to helper T cells during B-cell activation and the cytokines necessarily for Ig class switch NOT PRODUCED!!
- Low IgA, IgG, and IgE result in recurrent pyogenic infections (due to poor opsonization), especially at the mucosal sites
Wiskott-Aldrich Syndrome characterized by? due to?
- thrombocytopenia, eczema, recurrent infections (defective humoral and cellular immunity); bleeding a major cause of death
- mutation in WASP gene; X-linked
Complement deficiencies
C5-C9: increased risk for Neisseria infection;
C1 inhibitor: hereditary angioedema, characterized by edema of the skin (especially periorbital) and mucosal surfaces
For autoimmune disorders, what are they characterized by? involves what? who? Cause?
- immune-mediated damage of tissues (1% prev in US)
- loss of self-tolerance (self-reactive lymphocytes regularly generated but UNDERGO APOPTOSIS with negative selection in thymus or bone marrow OR become anergic (recognition of antigen in peripheral lymphoid tissues with no second signal)
- More common in women; classically women of childbearing age
- likely an environmental trigger in genetically suscpetible individuals (increased incidence in twins and certain HLA subtypes)
SLE: what is it; clinical features; characterizations? Other associations?
- systemic autoimmune disease: Ab’s against host damage multiple tissues via type II (cytotoxic) and type III (antigen-antibody complex) hypersens;
- fever, weight loss, BUTTERFLY RASH (sunlight), arthirits, pleuritis, pericarditis, CNS psychosis, renal damage (diffuse proliferative glomerulonephritis is most common injury), endocarditis (Libman-Sacks with small sterile deposits on both sides of mitral valve), myocarditis, pericarditis, TAL, renal failure and infection (death)
- antinulear antibody (sens, not spec) and anti-dsDNA antibodies (highly specific);
antihistone Ab = drug-induced SLE (caused by hydralazine, procainamide, isoniazid) - Antiphospholipid antibody syndrome associated with SLE: autoantibody against proteins bound to phospholipids, most effective being anticardiolipin and lupus anticoagulant (lead to false-pos syphilis test and falsely-elevated PTT respectively), arterial and venous thrombosis include DVT, hepatic vein thrombosis, placental thrombosis, stroke; requires LIFELONG ANTICOAG
Sjogren syndrome: involves? presentation? Characterized by? associations? increaed risk for what?
- autoimmune destruction of lacrimal and salivary glands (lymphocyte-mediated damage, or type IV hypersen, with fibrosis
- dry eyes (keratoconjunctivitis), dry mouth (xerostomia), and recurrent dental caries in older woman (50-60 years): CAN’T CHEW A CRACKER, DIRT IN MY EYES
- ANA, anti-ribonucleoprotein antibodies (anti-SS-A/Ro and anti-SS-B/La)
- autoimmune diseases, especially rheumatoid
- increased risk for B-cell (marginal zone) lymphoma, which presents as unilateral enlargement of parotid gland late in disease course
My mom, a 55 yo woman, noticed she couldn’t eat or really chew anything. This was the 4th time this has happened in her life; she finds it annoying when her eyes and mouth dry up, and her teeth are painful. Her name is Anna, and with her friends ROsie and LArry, they noticed she’s starting to get swan-like hands. Oh boy, is that something swelling up along her neck?
Scleroderma is what? how is it divided?
Autoimmune disease characterized by activation of fibroblasts and deposition of collagen (fibrosis);
localized scleroderma and systemic sclerosis
For localized scleroderma, what does this involve?
JUST SKIN: most common subtype is morphea, and highly associated with antibodies to DNA topo II
For systemic sclerosis, what does that involve? How is this broken up?
- skin and visceral organs
- Limited type: limited areas of skin (mostly hands, face, and neck) with late visceral involvement and prototype is CREST syndrome (Calcinosis/anti-Centromere Ab’s, Raynaud phenomenon, Esophageal dysmotility, Scelrodactyly, and Telangiectasias of the skin);
Diffuse type: involves skin and can involve any visceral organ; GI tract (GERD, dysphagia), lungs (interstitial fibrosis, pulmonary HTN) and kidneys (malignant HTN leading to renal failure) commonly involved
The assistant dean said I need to eat more fiber and that’ll get my colon working. Then I’ll have my choice of schools: if I go local, I’ll have to back up morphea, and have to look at Topo Jr’s abs. But if I go widely, I’ll just make sure that I consider playing multiple positions and not LIMIT my chances: I’ll brush my teeth with Crest if need be to impress the coach. If I stay diffuse and get playing time, I’ll have to watch out for problems down the line: GI, lungs, kidneys
Mixed CT disease; involves what? characterized by what?
autoimmune-mediated tissue damage with mixed features of SLE, systemic sclerosis, and polymyositis;
serum Ab’s against U1 ribonucleoprotein