Immunodeficiencies Flashcards

1
Q

Associated infections with T cell deficiencies

A
Viral 
Fungal
yeast 
Atypical microorganisms
Cancer
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Associated infections with B cell and phagocyte deficiencies

A

Microorganisms requiring opsonization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

associated infections with complement deficiencies

A

Resemble b cell deficiencies: Microorganisms requiring opsonization.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Two categories of immunodeficiencies

A

Primary (congenital)
Genetic anomaly- inherited or mutation (sporadic)
Generally more severe

Secondary (acquired)
Caused by another illness
More common

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

5 groups of Primary ID

A
B lymphocyte def (50%)
T lymphocyte def (30%)
Phagocyte def 
Complement def
Combined B and T cell def
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What kind of defect is a primary ID

A
Usually single gene. Mostly sporadic (75%) 
Family history (25%)

manifest early in life- first 2 years.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

two B lymphocyte deficiencies

A

Hypogammaglobulinemia (low Ab) or agammaglobulinemia (no Ab)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Hypogammaglobulinemia

A

Type of B lymph Deficiency. Low Ab production

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

agammaglobulinemia

A

Type of B lymph Deficiency. No Ab production

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the two causes of B lymphocyte deficiencies?

A

Receptor defects: Ineffective intracellular signaling. BCR and cytokine receptors. Wont get full activation.

Ab class switch defect: Altered ability to change Ab class. due to co-stimulatory signal defect.

(B cell needs CD4, cytokine, and costimulatory signal to fully activate and class switch)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

3 types of B lymphocyte deficiencies

A

Brutons (X-linked) Agammaglobulinemia
Common Variable Immunodeficiency (CVID)
Selective IgA deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Brutons (X-linked) Agammaglobulinemia

A

Most severe B lymphocyte deficiency.
Receptor defect.
no mature B cells.
Recurrent bacterial infections.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Common Variable Immunodeficiency (CVID)

A

Most common primary immune deficiency (1 case in 25,000)
Class switch defect. Lacking IgG, M, and A.
Onset of symptoms delayed until late 20s.
Results in recurrent bacterial respiratory infection and increased cancer risk.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Most common primary immune deficiency (1 case in 25,000)

A

Common Variable Immunodeficiency (CVID)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Selective IgA deficiency

A

Unable to produce IgA Abs. Causes compromised secretory immune system.

Severe allergies and recurrent sinus/lung/Gi infection.

Severe mucopurulent conj.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Primary T cell immunodeficiencies

A
DiGeorge Syndrome/22q11.2 Deletion Syndrome
Severe combined immunodeficiency (SCID) 
Reticular Dysgenesis (type of SCID)
17
Q

DiGeorge Syndrome/22q11.2 Deletion Syndrome

  • What causes it?
  • What systems are affected?
  • What infections are common?
  • Incidence?
  • how many cases are sporadic?
A

Partial or complete absence of T cell immunity (CD4 and CD8)

Due to thymus aplasia or hypoplasia (prevents development of thymus)

Causes endocrine (bc parathyroid also not developed right), vascular, and facial abnormalities (cleft pallet)

Higher viral and fungal infections (due to CD8 loss) and bacterial infections (due to CD4 loss)

Higher incidence of autoimmune diseases.

90% of cases are sporadic. People who have this disease are unlikely to pass down- don’t live long.

18
Q

Severe combined immunodeficiency (SCID)

  • What kind of deficiency?
  • Possible causes
A

Combined T and B cell deficiency
Possible causes:
1. Toxic metabolic byproducts of bone marrow.
2. Cytokine receptor defects
3. VDJ recombination defects in clonal diversity
4. TCR doesn’t have proper proteins. Could be bare Class I: no Tc or CD8. or Could be bare on Class II: No CD4 or Th (most severe. Without, can’t activate humoral or cytotoxic)

19
Q

Reticular Dysgenesis (type of SCID)

A

Most severe form of SCID
Absent/defective stem cells results in no circulating lymphocytes or granulocytes (neutrophils, basophils, eosinophils)
Usually fatal before or after birth.
Bubble boy?

20
Q

Complement deficiencies

  • What do they resemble?
  • What infections result
  • 2 kinds of complement deficiencies
A

Resemble B lymphocyte deficiencies
Results in bacterial infections

  1. C3 deficiency. Bad bc focal part of complement activation.
  2. Terminal component deficiency. Never form MAC. Causes 8000x risk of neisseria infection.
21
Q

Phagocytic deficiencies

  • Resemble what?
  • What types of infections?
  • 4 types of phagocytic deficiencies
  • What is chronic granulomatous disease
A

Often resemble B lymphocyte deficiencies
Bacterial infection

Types:

  1. Neutrophil maturation defect.
  2. Adhesion molecule defect. Neutrophils can’t adhere to endothelial vessels, making it hard for them to extravasate.
  3. Opsonin receptor defect. Neutrophils can’t find pathogens.
  4. Pathogen killing defect. Can engulf, but not kill pathogen- lack ROS in phagolysosome.

Chronic granulomatous disease:
Pathogen killing defect. Absent ROS in phagolysosome. Causes recurrent granuloma in points of exposure- lungs, GI, skin.

22
Q

Chronic granulomatous disease

A

Phagocytic deficiency.

Pathogen killing defect. Absent ROS in phagolysosome. Causes recurrent granuloma in points of exposure- lungs, GI, skin, lymph nodes, stomach.

23
Q

causes of secondary deficiencies

A
#1 cause: Protein malnutrition. 
Pregnancy, aging that deplete immune system
Stress
Metabolic or genetic. Ex: Diabetes 
Malignancies could cause direct effects (due to tumor) or indirect (due to suppressed immune system, other infections can easily occur that could cause death) 
Trauma
Surgery, steroids 
Infections
24
Q

What kind of virus is HIV and what does it infect

A

RNA retrovirus. RNA in the virus capsule, DNA once it is in our cells and then incorporates into our DNA.

Infects CD4 Th1 cells mostly, but can also target neurons, Gi epithelial cells, and macrophages.

25
Q

Who is most likely to contract HIV

A

Males having sex with males

AA > latino > white

26
Q

3 phases of HIV

A

Acute phase: mono like symptoms 3-6 weeks after contracting.

Clinic latency phase: Asymptomatic period 2-10 years after infection without treatment. 500+ CD4 cells per mm^3 of blood.

AIDS: CD4 cell count less than 200 mm^3 in blood or aids defining condition (rare infections you don’t get unless your immune system is wiped out)

27
Q

Normal Cd4 cell count

A

500-1500 cells per mm^3 of blood

28
Q

HIV related abnormalities(4)

A

Lymphopenia: Low Cd4 count. Less than 200

Cutanous anergy: Defect in cell mediated immunity. Inappropriate skin response. Ex: inoculated with something. Should have skin reaction, but don’t.

Hypergammaglobulinemia: If pt has had epstein-Barr virus in the past, it may re-emerge since immune system is wiped out. Will cause B cells to produce Abs with no regulation.

CD4: CD8 ratio usually between 1-4. If less than 1, indicative of Aids.

29
Q

Lymphopenia:

A

Low Cd4 count. Less than 200

30
Q

Cutanous anergy:

A

Defect in cell mediated immunity. Inappropriate skin response. Ex: inoculated with something. Should have skin reaction, but don’t.

31
Q

Hypergammaglobulinemia:

A

If pt has had epstein-Barr virus in the past, it may re-emerge since immune system is wiped out. Will cause B cells to produce Abs with no regulation.

32
Q

Normal CD4:CD8 ratio

A

Between 1-4. If AIDS, will be less than 1.

33
Q

Most common aids defining infection

A

Pneumocystis jiroveci pneumonia and systemic candidiasis (yeast infection)

34
Q

CBC with differential

A

Complete blood count (WBC, RBC, platelets) with differential (WBC subtypes: Neutrophils, monocytes, MO)

35
Q

Ways to evaluate immunity

A
  1. CBC with differential
  2. Classes and conc of Ig in the blood
  3. Assay for complement proteins
  4. Skin tests. Ex: cutaneous anergy
36
Q

4 ways to treat immunodeficiencies

A
  1. Gamma globulin therapy.
    - Effective for B cell deficiencies.
    - Transient. Must have injections often.
    - Low risk
  2. Transplantation or transfusion
    - Bone marrow or umbilical cord stem cells
    - Effective for some primary combined deficiencies
    - High risk of GVHD
  3. Treatment with soluble immune mediators. Injections for complement deficiencies.
  4. Gene therapy
37
Q

GVHD

A

Before graft, person’s immune system will be wiped out. When they put in graft, the graft might attack the HOSt. bad.