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Flashcards in Immuno - deficiencies Deck (20):
1

Recurrent bacterial/enterovial infections after age of 6mos (after loss of maternal IgG), young boys

X-linked agammaglobulinemia

B's! Defect in BTK, no B-cell maturation, X-linked recessive (more common in Boys)

Look for absent B cells in peripheral blood and low number of all immunoglobulins

Absent lymph nodes!

2

Airway/Gi infections, Autoimmune disease, Atopy (though often asymptomatic!)

Selective IgA deficiency

Anaphylaxis to IgA-containing products

Look for selectively decreased IgA levels

3

Autoimmune diseases, brochiectasis, lymphoma, sinopulmonary infections, acquired in 20s-30s

Common variable immunodeficiency

Defect in B-cell differentiation

Decreased plasma cells and decreased immunoglobulins

4

Tetany, recurrent viral/fungal infections, conotruncal abnormalities (Tetralogy of Fallot, truncus arteriosus), absent thymus/parathyroids (no appearance on CXR)

Thmyic aplasia (DiGeorge) - 22q11 deletion, detected by FISH

failure to develop 3rd and 4th branchial pouches

T cell disorder

Decreased T cells, PTH, Ca2+

5

Disseminated mycobacterial and fungal infections; appears after BCG vaccine (decreased Th1 response)

IL-12 deficiency

Decreased Th1 response. Autosomal recessive.

Decreased IFN-y

6

coarse Facies, Abscesses, Teeth, increased igE, Derm lesions (FATED), seen in babies!

hyper-IgE syndrome (Jobs)

deficiency of Th17 cells due to STAT3 defect --> impaired neutrophil recruitment to site of infection

autosomal dominant

7

Noninvasive Candidal infections of the skin and mucus membranes

Chronic mucocutaneous candidiasis

T-cell dysfunction, absent T cell proliferation to Candidal antigens

8

Failure to thrive, chronic diarrhea, thrush, absence of thymus/lymph node germinal centers/T cells

Recurrent bacterial, viral, fungal infections, esp. opportunistic infxns

Severe combined immunodeficiency (SCID)

Major types: IL-2R deficiency, adenosine deaminase deficiency (decr. purine salvage)

tx: bone marrow transplant (no concern for rejection)

9

Triad of : Cerebellar defects, spider angiomas/telengiectasias, IgA deficiency

Also, lymphopenia, decr. immunoglobulins

Ataxia-telengiectasia

Defects in ATM gene --> failure to repair DNA double stand breaks --> cell cycle arrest

incr. AFP, decr. IgA/G/E, lymphopenia

Also, hypersensitivity to ionizing radiation

10

Severe pyogenic infections, opportunistic infections (Candida, PCP, CMV), only IgM present, Early in life!

Hyper-IgM syndrome

Defective CD40L on T cell leads to inability for B cells to undergo class-switching

11

Thrombocytopenic purpura, eczema, recurrent infections

Incr. risk of autoimmune disease and malignancy

Wiskott-Aldrich (WATER)

Mutation in WAS gene = T cells unable to reorganize actin cytoskeleton

Fewer and smaller platelets

12

Absent pus, impaired wound healing, delayed separation of umbilical cord

Leukocyte Adhesion Deficiency type 1

Defect in LFA-1 integrin (CD18) on phagocytes --> impaired migration and chemotaxis

Increased neutrophils, but absence at infection sites

13

Recurrent staph/strep infections, partial albinism, peripheral neuropathy, neurodegeneration

Chediak-Higashi

Defect in lysosomal trafficking regular gene (LYST)

Microtubule dysfunction in phagosome-lysosome fusion

Look for giant granules in granulocytes and platelets

14

Increased susceptibility to catalase + organisms (Nocardia, Pseudomonas, Listeria, Aspergillus, Candida, E. coli, S. aureus, Serratia)

Chronic granulomatous disease

Defect of NADPH oxidase --> decreased ROS/respiratory burst in neutrophils

Abnormal dihydrorhodamine test

15

Transplant rejections

widespread thrombosis/ischemia/necrosis...
dense interstitial lymphocytic infiltrate...
vascular smooth muscle growth and parenchymal fibrosis...

Hyperacute
- type II hypersensivity
- ***widespread thrombosis/ischemia/necrosis***

Acute
- CD8 T cells activate against donor MHCs
- vasculitis with ***dense interstitial lymphocytic infiltrate***. Prevent with immunosuppressives!

Chronic
- CD4 T cells respond to recipient APCs presenting donor peptides, secrete cytokines, leads to ***proliferation of vascular smooth muscle and parenchymal fibrosis***

16

Graft-vs-host disease

Grafted T cells proliferate in the recipient due to immunocompromised status (usually after liver/BMT)

Also, rash, jaundice, diarrhea, HSM

Potentially beneficial after BMT for leukemia

17

Calcineurin inhibitors
IL-2 transcription blockers (block T-cell activation)

- cyclosporine (cyclophilin)
- tacrolimus (FKBP) less SE



both are very nephrotoxic

18

mTOR inhibitor
IL-2 response blocker (block T-cell activation and B-cell differentiation)

- sirolimus (binds FKBP)

not nephrotoxic, good for kidney transplant
causes anemia, thrombocytopenia

19

Nucleotide synthesis blocker

- azathioprine (6-MP precursor), good for other AI dzs

toxicity increased by allopurinol (6-MP degraded by xanthine oxidase)

20

Steroids

- NF-KB inhibitor, suppress cytokine transcription, iatrogenic Cushing syndrome