Immunodeficiencies Flashcards Preview

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Flashcards in Immunodeficiencies Deck (18):
1

Who are the B-cells disorders?

X-liked (Bruton) agammaglobulinemia
Selective IgA deficiency
Common variable immunodeficiency

2

Who are the T cell disorders

Thymic aplasia (Digeorge syndrome)
IL-12 deficiency
Autosomal dominant hyper IgE syndrome (Job syndrome)
Chronic mucocutaneous candidiasis

3

who are the B and T-cell disorders

Severe combined immunodeficiency
Ataxia-telangiectasia
Hyper IgM syndrome
Wiskott-Aldrich syndrome

4

Who are the phagocyte dysfunction disorders

Leukocyte adhesion deficiency (Type 1)
Chediak-Higashi syndrome
Chronic graulomatous disease

5

X-linked Agammaglobulinemia


Defect?
Presentation
Findings?

X-linked B cell disorder

Defect: BTK - tyrosin kinease gene
No B cell maturation

Presentation: Recurrent bacterial and enteroviral infections after 6 months (decrease maternal IgG)

Findings: absent B cells in peripheral blood. Low Ig of all classes.
Absent/scanty lymph nodes and tonsils

6

Selective IgA deficiency


Defect?
Presentation
Findings?
Contraints?

Most common primary immunodeficiency
B cell disorder

Defect: unknown

Presentation: Majority Asymptomatic
Can see Airway and GI infections, Atopy (allergy), Anaphylaxis to IgA containing products!!!

* Sinus and Lung infections

Findings: Decreased IgA with normal IgG, IgM levels.

7

Common Variable immunodeficiency

Defect?
Presentation?
Findings?

B cell disorder

Defect: B cell differentiation due to many causes

Presentation: acquired 20s-30s
Increase risk of autoimmune disease, bronchiectasis, lymphoma, sinopulmonary infections

Findings: Low plasma cells, low immunoglobulins

8

Thymic aplasia

Defect?
Presentation?
Findings?

Tcell disorder
DiGeorge syndrome

Defect: 22q11 -- failure to develop 3rd and 4th pharyngeal pouches
-absent thyroid and parathyroids (CALCIUM IMBALANCE)

Presentation: Tetany (hypocalcemia), recurrent viral/fungal/Protozoa infections (T cell deficiency) conotruncal abnormalities ( Teratoly of Fallot, truncus arteriosus)

Findings: Low T-cells, Low PTH, low Ca2+
Missing thymic shadow on CXR
22q11 deletion detected by FISH

9

IL-12 receptor deficiency

Defect?
Presentation?
Findings?

T cell disorder
Autosomal Recessive

Defect: decrease Th1 response

Presentation: Increase susceptibility to mycobacterial infections
-Disseminated mycobacterial and fungal infections. May present after administration of BCG vaccine

Findings: decrease INF-gamma

10

Autosomal Dominant Hyper- IgE syndrome
(Job syndrome)

Defect?
Presentation?
Findings?

T cell disorder

Defect: Deficiency of Th17 cells due to STAT3 mutation; low IGF-gamma
- impaired recruitment of neutrophils to sites of infections

Presentation:
"FATED"
coarse Facies
staphylococcal Abscesses
retain primary Teeth
increase IgE
Dermatological problems ( eczema)

Findings: High IgE, low IFN-gamma, Eosinophils present

11

Chronic mucocutaneous candidiasis

Defect?
Presentation?
Findings?

Defect: T-cell dysfunction due to many causes

Presentation: non -invasive Candida albicans infections of skin and mucous membranes

Findings:
absent in vitro T-cell proliferation response to Candida antigens

12

Severe combined immmunodeficiency

Defect?
Presentation?
Treatment?
Findings?

Autosomal recessive (B and T cell disorder)

Defect: Adenosine deaminase deficiency

Presentation:
Triad:
1. severe recurrent infections
- chronic mucocutanous candidasis (thrush)
-fatal/recurrent RSV, VZV, HSV, measles, Flu, parainfluenza
-Pneumocystis jirovecii pneumonia

2. Failure to thrive

3. Chronic diarrhea

Tx. bone marrow transplant (no concern for rejection)

Findings: low T cell receptor excision circles (TRECs); absence of thymic shadow in newborn, absence of germinal centers in lymph node biopsy

13

Ataxia-Telangiectasia


Defect?
Presentation?
Associated findings?
Findings?

B and T cell disorder

Defect: defect in ATM gene --- failure to repair DNA double strand breaks --> cell cycle arrest

Presentation: Triad
1. cerebellar defects ( Ataxia)
-poor smooth persuit of eyes
2. spinder Angiomas
3. IgA deficiency

-increase risk of cancer: lympoma and acute leukemias
- Radiation sensitivity!

Findings:
high AFP
Low IgA, IgG, and IgE
Lymphopenia, cerebellar atrophy

14

Hyper IgM syndrome


Defect?
Presentation?
Findings?

X-linked Recessive B and T cell disorder

Defect: defective CD40L on Th cells
- class switching defect

Presentation:
Severe pyogenic infections early in life. Opportunistic infections with Pneumocystiss and Cryptosporidium and CMV
-recurrent sinopulmonary infections

Findings: High IgM and LOW IgE, IgA, and IgG,

15

Wilskott-Aldrich syndrome

Defect?
Presentation?
Findings?

X-linked recessive B and T cell disorder

Defect: Mutation in WAS gene; T-cells unable to reorganize actin skeleton

Presentation: WATER
-Wiskott-Aldrich
-Thrombocytopenic purpura
-Eczema on trunk
-Recurrent pyogenic infections

Increase risk of autoimmune disease and maliganancy

Finding:
- Decrease to normal IgG, IgM
- increase IgE and IgA
- fewer and smaller platelets

16

Leukocyte adhesion deficiency (type 1)

Defect?
Presentation?
Findings?

Autosomal Recessive phagocytic dysfunction

Defect: LFA-1 Integrin protein on phagocytes
- impaired migration and chemotaxis

Presentation: Recurrent bacterial skin and mucosal infections
- Absent pus formation
- Impaired wound healing
- Delayed separation of umbilical cord

Findings:
high neutrophils
-absence of neutrophils at infection sites

17

Chediak-Higashi syndrome

Defect?
Presentation?
Findings?

Autosomal recessive Phagocyte dysfunction defect

Defect: Lysosomal trafficing regulator gene (LYST)
-microtubule dysfunction in pahgosome-lysosome fusion

Presentation:
Recurrent pyogenic infections by staph and strep; partial albinism, peripheral neuropathy

Findings:
Gian granules in granulocytes and platelets
Pancytopenia
Mild coagulation defects

18

Chronic granulomatous disease

X-linked Phagocyte dysfunction

Defect: Defect of NADPH oxidase
-decrease in respiratory burst in neutrophils

Presentation:
Increase susceptibility to catalase positive organisms:

"Need PLACESS"
Nocardia
Pseudomonas
Listeria
Aspergillus
Candida
E.coli
S.aureus
Serratia

Finding: abnormal dihydrorhodamine (flow cytometry) test
Nitroblue tetrazolium dye reduction test is negative
- dye usually gets metabolized into blue color in phagocytes and failure to do so is diagnosis for CGD