Immunodisorders Flashcards
Digeorge Syndrome (aka Thymic Hypoplasia)
Cx: During Embryologic development there is a failure in the 3rd and 4th pharengeal pouch development
Gene Deletion 22q11
Sx: Decreased/No T Cells in blood
Ig levels maybe normal or Low
Tetany (This tells you that the Parathyroid gland also failed to develop)
Heart and vessel defects
Facial Abnormalities
Sever Combined Immunodeficiency (SCID)
Combined B and T Cell Deficiency
AR: Adenosine Deaminase Mutation (#1)
Adenosine Accumulation which is cytotoxic to B and T Cells
Sx: Prominent Thrush and Diaper Rash (Candidiasis Albicans)
Morbilliform Rash (Measles like rash) (Maternal attack)
Decreased Immunoglobulins
NOTE: Bone Marrow Transplant will have NO chance of rejection
Sever Combined Immunodeficiency (SCID)
Combined B and T Cell Deficiency
XR: Cytokine Receptor Defect
No B or T Cell Maturation
Sx: Prominent Thrush and Diaper Rash - (Candidiasis Albicans)
Morbilliform Rash (Measles like rash) (Maternal attack)
Decreased Immunoglobulins
Sever Combined Immunodeficiency (SCID)
Combined B and T Cell Deficiency
AR: Jak 3 Mutation
Impairs MHC II protein expresion
Sx: Prominent Thrush and Diaper Rash (Candidiasis Albicans)
Morbilliform Rash (Measles like rash) (Maternal attack)
Decreased Immunoglobulins
Wiskott Aldrich Syndrome
B and T Cell Defect
Cx: XR, WASP gene defect (Wiskott Aldrich Syndrome Protein)
Sx: KEY TRIAD - Eczema, thrombocytopenia, recurrent sinopulmonary pyogenic infections.
Test: Immunoglobuline assay - decreased IgM, NORMAL IgG, Elevated IgA and IgE
Tx: Bone Marrow Transplant
NOTE: Strong chance to develop Non-Hodgkins B Cell Lymphomas
C5-C9 Defects
Normally produces the MAC Complex in the compliment cascade
Defects in any of these lead to increased risk of Neisseria infections
C1 Esterase Inhibitor Deficiency “Hereditary Angioedema”
Normally inactivates the C1 protease (Active C1)
AD
Sx: Episodes of edema of the skin and mucosal surfaces with stress or trauma
Strong suffocation risk
Paroxysmal Nocturnal Hemaglobinurea
Cx: Defect in the anchor for Decay Accelerating Factor (DAF) - Normally destabalizes C3 and C5 attachment to blood cells (RBCs, platelets, leukocytes)
Intravascular Hemolysis (RBCs are destroyed in the blood vessels)
This happens when the patient sleeps when there is normally a slight acidification of the blood. This increases C3 and C5 causing hemolysis. That means the first time the patient urinates when they wake up there may be small hints of hematuruia
Sx: Pancytopenia
HIV/AIDS Proteins and Progression of Disease
HIV Envelop Proteins - Gp120 and Gp 41
Gp120 attaches to CD4 receptors on CD4 T Cells resulting in a confirmational change
CCR5 and CXCR4 proteins on the T cells move closer and allow the virus to firmly bind and insert gp41 into host cell membrane
HIV Directly invades CD4 T Cells, eliminating this individual cells ability to assist in cell mediated immunity –> AIDS
HIV Converts viral RNA into DNA and incorporates it into host genome
Immune system mounts typical Cell and Humoral mediated response resulting in “Acute Phase Mononucleosis like symptoms”, Lasts 3-7 wks
Very slow infection rate allows dormancy period
CD4 T Cell counts usually stay above 500 (Normal) for years
CD4 T Cell count falls between 200-500, early stage of symptoms (NOT AIDS yet)
CD4 T Cell <200 officially AIDS
HIV/AIDS Transmission
In order: Sexual, IV Drugs, Vertical, Accidental needle stick.
HIV/AIDS Tests
Tests: ELISA: Detect anti-gp120 antibodies
Sensitivity is 100% (TP/(TP+FN)
IF POSITIVE –> Western blot
Detect anti-gp41 antibodies, p24, gp120, gp160 viral proteins
Specificity 100% (TN/(TN+FP)
Other infected cells by HIV/AIDS
Lymph node follicle Dendritic cells and Macrophages are Reservoir cells
Monocytes and Macrophages carry virus to the brain
Mucosal Dendritic Cells carry to B Cells (Think Strep Pneumo/Hemophilis B/Candidiasis with Decreased Humoral Response)
HHV-8 Infection
Kaposi Sarcoma (Bright red/purple skin cancer) Kaposi Sarcoma Progression: Flat Red/Purple discolorations-->Red/Purple raised plaques-->Red/Purple Nodules-->Ulcerations. (Can be oral or GI) One of these can appear in healthy individuals, AIDS patients get a lot of them at the same time. KEY difference
Systemic Candidiasis Albicans Infections
Oral Thrush #1 Fungal infection in AIDS patients
Toxoplasmosis
CNS Calcifications
Usually get from cats
EBV
CNS Lymphomas
Neoplasia
Cytomegalovirus
Blindness #1 Cx in Aids
Amyloid Light Chain (AA)
Systemic distribution
Immunoglobulin (Ig) light chains produced by plasma cells. Aka “Bence-Jones Proteins”
Associated with Multiple Myeloma **
Test: Immunoelectrophoresis (Detects Light Chains)
Amaloid Associated (AD)
Unique non-Ig proteins
Systemic circulation
Associated with Chronic Inflammation/Infection
Ankoloysis Spondalitis (HLA-B27), Inflammatory Bowel Disease, Rheumatoid Arthritis, TB