Immunology Flashcards
X-linked (Bruton) agammaglobulinemia
Defect in BTK, a tyrosine kinase gene which results in no B cell maturation. XR. Common in Boys. Recurrent bacterial and enteroviral infections after 6 months old. **dec Ig of all classes, absent/scant lymph nodes. **Normal CD19+ B cell count, dec pro-B.
Selective IgA deficiency
Most common 1° immunodeficiency. Asymptomatic, can see Airway and GI infections, Autoimmune disease, Atopy, Anaphylaxis to IgA-containing products. IgA<7mg/dL with normal IgG and IgM levels
Common variable immunodeficiency
defect in B-cell differentiation. Acquired in 20-30s, inc risk of autoimmune disease, bronchiectasis, lymphoma, sinopulmonary infection. Dec plasma cells and immunoglobulins
Thymic aplasia (DiGeorge Syndrome)
22q11 deletion; failure to develop 3rd and 4th pharyngeal pouch, absent thymus and parathyroids. Tetany (hypocalcemia), recurrent viral/fungal infections (T cell deficiency), conotruncal abnormalities (tetrology of fallot, truncus arteriosus). Dec T cells, dec PTH, dec Ca2+. **Absent thymic shadow on CXR, FISH detection of 22q11 deletion. **
IL-12 receptor deficiency
dec TH1 response. AR. Disseminated mycobacterial and fungal infections; may present after administration of BCG vaccine. decreased IFN-y (secreted by TH1 cells)
Autosomal dominant hyper-IgE syndrome (Job syndrome)
deficiency of TH17 cells due to STAT3 mutations so impaired recruitment of neutrophils to sites of infection. FATED: coarse Facies, cold (noninflamed) staphylococcal Abscesses, retained primary Teeth, inc IgE, Dermatologic problems (eczema). inc IgE and dec IFN-y
What is the role of IFN-y?
Secreted from TH1 cells and activates macrophages. Important in granuloma formation and maintainene.
Severe combined immunodeficiency (SCID)
defective IL-2R gamma chain or adenosine **deaminase deficiency. **Filaure to thrive, chronic diarrhea, thrush. Recurrent viral, bacterial, fungal, and protozoal infections. Dec T cell receptor excision circles (TRECs). Absense of thymic shadow, germinal centers and T cells on flow cyto,etru. Tx: bone marrow transplant (no concern for rejection, yippee)
Wiskott-Adlrich syndrome
mutation in WAS gene, T cells unable to reorganize actin cytoskeleton. WATER: Wiskott-Aldrich, Thrombocytopenic purpura, Eczema, Recurrent infection. Increased risk of autimmune diseas and malignancy. inc IgE and IgA, low/normal IgG and IgM
Chronic Granulomatous Disease
defective NADPH oxidase, dec ROS. Suseptible to PLACESS: Pseudomonas, Listeria, Aspergillus, Candida, E.coli, Serratia, Staph aureus (nocardia, burkholderia cepacia)
What drains to the para-aortic lymph nodes?
testes, ovaries, kidneys and uterus
What drains to the internal iliac lymph nodes?
lower rectum to anal canal (above pectinate line), bladder, vagina and prostate
What drains to the popliteal lymph nodes?
dorsolateral foot, posterior calf
What drains to the axillary nodes?
upper limb, breast, and skin above the umbilicus
What enters the right lymphatic duct?
drains right side of body above the diaphragm
What does the thoracic duct drain?
everything that the right lymphatic duct doesn’t get, and enters in the left subclavian and internal jugular veins.
Why are asplenic patients at higher risk for encapsulated bacterial infections?
No spleen means less IgM production and decreased complement activation therefore less C3b opsonization of encapsulated bacteria
What are the encapsulated bacteria that asplenic patients are suspetible to?
SHiNE SKiS (or Even Some Pretty Nasty Killers Have Shiny Bodies):
Streptococcus pneumoniae
H. influ
N. meningitidis
E. coli
Salmonella
Klebsiella pneumoniae
Group B Strep
Klebsiella
Which bacteria from that infect asplenic patients have vaccines?
S. pneumo, H. flu type B, and N. meningitidis
What pharyngeal pouch is the thymus from?
3rd pharyngeal pouch!
HLA-A3 association?
Hemochromatosis
HLA-B27 assocations?
PAIR.
Psoriatic arthritis
Ankylosing spondulitis
IBD arthritis
Reactive arthritis
HLA-DQ2/DQ8 associations?
celiac disease
HLA-DR2 assocations?
MS, hay fever, SLE, Goodpasture syndrome
HLA-DR3 associations?
DM1, SLE, Graves disease
HLA-DR4 assocations?
Rheumatoid arthritis, DM1 (4 walls in a rheum)
HLA-DR5 associations?
pernicious anemia leads to B12 deficiency, hasimoto thyroiditis
What is the role of TNF-alpha in granuloma formation?
Secreted from macrophages and maintains the granuloma. If on anti-TNF therapy then need to first make sure they don’t have TB, or else it will become reactivated and disseminated.
What receptor recognizes LPS of gram - bacteria?
CD14 (TLR4) on macrophages
What results from TLR activation via recognition of a PAMP?
upregulation os NF-KB whihch is a nuclear transcription factor that activates immune response genes leading to production of multiple immune mediators