Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Immunology > Primary and secondary immunodeficiencies > Flashcards

Primary and secondary immunodeficiencies Flashcards

1
Q

Name the 9 primary immunodeficiencies

A

x-linked agammaglobulinemia (XLA, Bruton disease)
selective IgA deficiencies
CVID (common variable immunodeficiency)
Thymic hypoplasia (DiGeorge Syndrome)
SCID (Severe combined immunodeficiency disorder)
genetic deficiencies of complement components
Hereditary angioedema
Wiskott-Aldrich
Ataxia-Telangiectasia

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

Name the 7 secondary immunodeficiencies

A 
cancer
diabetes
malnutrition
infection
renal disease
sarcoidosis
transplantation recipients
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the predominant feature of impaired immune function?

A

infection.
It is more severe and persists longer
frequent recurrences
and they don’t respond to ordinarily effective prescriptions

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

What are 3 other clinical signs of immunodeficiencies?

A
  1. physical development disorders noted at birth (birth defects)
  2. Failure to thrive
  3. Doesn’t achieve or maintain developmental milestones
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How many infections per year is normal for a “healthy” child?

A

4-8 upper respiratory infections per year through the first 10-12 years.
Mean duration is 8 days, but still normal for up to 14+ days. This can therefor span 6 months.
This can be even higher for kids in daycare or many siblings.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

In primary care, what are our strategies for dealing with an immunodepressed child? (4)

A
  1. Prompt and aggressive treatment of infections
  2. may need prophylactic prescriptions
  3. live virus vaccines should not be given (rotavirus, varicella, MMR, intranasal influenza, oral polio)
  4. If blood transfusion is necessary, give irradiated, leukocyte poor, virus free blood.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Which vaccines might contain live virus? (5)

A

rotovirus, varicella, MMR intranasal influenza, oral polio

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

Primary immunodeficiencies can be categorized 6 ways

A
  1. B-cell deficiencies
  2. T-cell deficiencies
  3. Combined b and t cell
  4. complement deficiencies
  5. defective phagocytes
  6. unknown (idiopathic)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

If you suspect a primary immunodeficiency, what are some labs you could order (5)?

A
  1. CBC with peripheral smear
  2. lymphocyte immunophenotyping B and T cell types
  3. quantitative immunoglobulins (IgG, IgM, IgA)
  4. Ab titer
  5. protein electrophoresis (serum protein SPE)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe XLA

A

it is a primary humoral immunodeficiency characterized by severe hypogammaglobulinemia Ab deficiency and increased susceptibility to infection.
Virtual absence of B cells, very low levels of immunoglobulins, normal T-cell responses (cell-mediated immunity is intact)

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

Why does XLA occur?

A

Due to a mutation in the gene encoding Bruton tyrosine kinase (Btk) which is an important signal transduction protein. No B cells = no humoral immunity = no antibodies. This is X-linked.

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

What is the incidence of XLA?

A

1 in 379,000 live births. and 1 in 190,000. Mostly young boys and female carriers are immunocompetent

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

What is the clinical presentation of XLA? (4)

A
  1. symptoms present at about 6 mo old (when maternal Ab no longer present)
  2. recurrent pyrogenic bacterial infections (otitis media, sinusitis, pneumonia from strep pneumoniae and H. influnenzia)
  3. may have absence of inflamed tonsils and enlarged lymph nodes with recurrent otitis.
  4. Failure to thrive/growth delay
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Treatment of XLA

A

Replacement of immunoglobulin is the cornerstone of treatment.
IgIV or IGSC (subQ)
The dose is determined by weight, trough levels of IgG and the clinical response of the pt.
This reduces number and intensity of infections. You also want to council them about the risks of blood and plasma transfusions.

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

Describe Selective IgA deficiency (SIgAD)

A

Decreased serum IgA levels with normal serum levels of IgG and IgM, in the absence of any other immune disorder.

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

When do we diagnose IgA deficiency?

A

The diagnosis should only be made after age 4, since antibody levels in younger children can be depressed in the absence of any immune disfunction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the incidence of IgA deficiency?

A

1-500 to 700 ppl. Approximately 3% of the population. Lower in Asian populations, higher in caucasian populations. May be associated Epstein Barr, and Rubella.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the pathology of IgA deficiency?

A

Defect is the inability to terminally differentiate and mature into IgA secreting plasma cells.
Serum IgA levels are low. Less than 5mg per deciliter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the clinical presentation of IgA deficiency?

A
  1. 90% are asymptomatic (incidental finding)
  2. There is an increased incidence of sino-pulmonary infection as well as infections of the GI tract, conjunctiva, and respiratory tract.
  3. increased incidence of allergies, asthma, and autoimmune disease.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How do we treat IgA deficiency?

A

Discontinue meds that cause a drop IgA drop (examples include penacilamine, and valproic acid)

No specific treatment, but prompt appropriate abx therapy for recurrent infections.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is CI for patients with IgA deficiency?

A

Blood transfusions

no gamma globulin (anaphylactic hypersensitivity may occur type 1) Cross reaction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Describe Common Variable Immunodeficiency

A

CVID is impaired B cell differentiation with defective immunoglobulin production.

Here we have markedly reduced serum concentration of IgG’s along with low levels of IgA and or IgM.

Also defined by poor or absent response to immunizations.

Also absence of any other defined immunodeficiency state.
CVID
In other words, CVID is a collection of hypogammaglobulinemia syndromes resulting from many genetic defects.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

When does CVID typically present?

A

In the second to fourth decades of life.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is the pathology of CVID?

A

We have normal levels of B lymphocytes, but
they are phenotypically immature B lymphocytes.
They can still recognize Ag and respond with proliferation, but they are impaired in their ability to become memory B cells and mature plasma cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is the presentation of CVID?

A 
Recurrent sino-pulmonary infections, including: 
sinusitis
otitis
bronchitis
pneumonia
TB
fungal infections
(Respiratory failure is principle cause of death)

Also have evidence of immune disregulation leading to autoimmunity, inflammatory disorders, and malignant diseases:
chronic lung disease
GI and liver disorders
Granulomatous infiltrations of several organs
lymphoid hyperplasia
splenomegaly
malignancy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Why would recognition of CVID be delayed?

A

The clinical manifestations affect multiple organ systems. Patients often have been evaluated by several specialists by the time they are diagnosed, and there is an average of 5-7 years between onset of symptoms and the diagnosis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

When should we consider the diagnosis of CVID?

A
  1. chronic pulmonary infections, some of whom will present with bronchiectasis (abnormal widening of the bronchi)
  2. chronic intestinal diseases (chronic giardiasis, intestinal malabsorption, atrophic gastritis with pernicious anemia)
  3. signs and symptoms highly suggestive of lymphoid malignancy, including: fever, wt. loss, anemia, thrombocytopenia, splenomegaly, generalized lymphadenopathy, and lymphocytosis)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is treatment of CVID?

A

IGIV (premedicate to prevent a rxn to the IgA)

ABX (initiate earlier, give longer, with early signs of infection)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Which immunizations do you have to be careful with for a pt. with CVID?

A

MMR and Varicella: give them apart from IVIG.

30
Q

What are important T cell functions? (4)

A
  1. control viral disease
  2. control fungal disease
  3. monitor and control abnormal cell growth
  4. provide helper function to b cells for effective humoral response.
31
Q

Describe DiGeorge syndrome (aka. thymic aplasia)

A

Defective development of the pharyngeal pouch system. These are embryological structures that give rise to the thymus, thyroid, and parathyroid, maxilla, mandible, aortic arch, cardiac outflow tract, and the external and middle ear.

32
Q

What is the cause of DiGeorge syndrome?

A

Heterozygous deletion at chromosome 22.
Absence of development of thymus, thyroid and parathyroid glands:
congenital hypothyroidism
congenital hypoparathyroidism (low serum Ca), could be born with tetany

Most importantly for our discussion, and absence of mature T-cells.

33
Q

What is the result of the T-cell absence seen with DiGeorge syndrome?

A
  1. severe viral, fungal, and or protozoan infections.
  2. Occur in affected infants early in life
  3. pneumonia that is caused by pneumocystis jirovecii and thrush
34
Q

What is the prevalence of DiGeorge syndrome?

A

1 in 3,000-6,000 live births

35
Q

How do DiGeorge babies present at birth

A

(BUBBLE BABY)

  1. cardiac abnormalities and hypocalcemia with possible tetany
  2. facial abnormalities

If they survive,

No thymus or a hypo functioning thymus

  1. variable immune defect, but b-cells are normal, and t-cells are reduced.
  2. those with no thymus have profound T cell dysfunction and reduced CD4-T cells.
  3. Humoral immunity is normal and can produce Ab’s
36
Q

Clinical management of patients with DiGeorge’s syndrome?

A

Immediate treatment of cardiac abnormalities if indicated.
Control metabolic abnormalities
Only irradiated blood can be given to avoid (graft vs. host disease) reaction.
Once they are stable, these pts. are more suceptible to chronic rhinitis, pneumonia, yeast infections, and diarrhea.
If recurrent infections or FTT or severe T-cell deficiency, then you consider a thymus transplant from stillbirths

37
Q

Describe Severe Combined Immune Deficiency (SCID)

A

A group of inherited diseases caused by mutations in different genes whose products are crucial for the development and function of both B and T cells.

These are termed to SEVERE if they lead to early death from overwhelming infection, typically in the first year of life.

38
Q

Pathophysiology of SCID? (6)

A
  1. absence of normal thymic tissue and other other lymph tissues; devoid of lymphocytes.
  2. Immunoglobulin levels very low.
  3. tonsils and lymph nodes absent
  4. both b and t cells are defective
  5. in some children, the B and T cells are completely absent
  6. IN others, the number of cells is normal, but they don’t function properly
39
Q

What are the two main genetic types of SCID?

A

X-linked (75%)

and autosomal (25%)

40
Q

Describe x-linked SCID

A

Some pts. with X-linked SCID have a defect in the IL-2 receptor on T-cells.
Normal number of B-cells, but greatly reduced T-cells.
Low levels of IgG and IgA, you can make IgM, which provides some protection, but this is still fairly lethal.

41
Q

Describe autosomal SCID (three kinds)

A
  1. Mutation on the gene encoding a tyrosine kinase called ZAP-70. that plays a role in signal transduction of T-cells.
  2. Another autosomal form has mutations in the gene for a different kinase called Janus kinase 3.
  3. Mutation in RAG-1 or RAG-2 genes
42
Q

Clinical presentation of SCID (6)

A
  1. FTT, usually die within 1-2 years from infection
  2. pneumocystis pneumonia is the most common presenting infection.
  3. viral infections such as varicella/zoster infections, cytomegalo virus, RSV
  4. Chronic diarrhea and diaper rash
  5. severe thrush
  6. susceptible for complete range of MO’s
43
Q

Treatment of SCID

A

Bone marrow or cord blood transplantation may restore immunity. this is the only known cure. Transplants done within the first 3 months of life have the best success rate, and the pt. doesn’t not require immunosupressant drugs.

IVIG
Enzyme replacement therapy

44
Q

Describe hereditary angioedema

A

This is an uncommon autosomal dominant disease.
It is caused by a deficiency of the C1 inhibitor. The end result being we don’t regulate bradykinin, which causes capillary permeability leading to edema.
Characterized by episodes of edema in body parts, notably the hands, feet, face, and airway passages.

45
Q

What is the clinical presentation of hereditary angioedema?

A

In addition to the aforementioned swelling:
Bouts of excruciating abdominal pain, nausea, vomitting, caused by swelling of intestinal wall.
Acute emergency is the airway swelling.
Non-pruitic swelling
Lasts 24-72 hours
occurs spontaneously or from trauma
laryngeal edema can be fatal
increased incidence of autoimmune disease (SLE, Sjogrens syndrome, Chron’s disease, and scleroderma)

46
Q

Management of hereditary angioedema

A

Acute, immediate assesment of airway
Be ready to intubate

patients with any severity of laryngeal attack, severe GI attacks, or severe cutaneous attacks, should be treated with first line therapy

Epi and antihistamines get poor response because this isn’t a type 1 hypersensitivity

47
Q

What are first line therapies

A
  1. human plasma derived C1 inhibitor concentrate.
  2. recombinant C1 inhibitor
  3. icatibant: a bradykinin B2 receptor antagonist
  4. ecallantide: a kallikrein inhibitor
48
Q

What is the most common cause of immunodeficiency worldwide?

A

malnutrition

49
Q

How does PEM affect the immune system?

A
  1. impairment of cell mediated immunity
  2. phagocyte function depressed
  3. complement system impaired
  4. decrease in IgA
  5. cytokine production issues
50
Q

Which Vitamin deficiencies can affect immune function?

A

Vit. A
Vit. C
Vit. B12
Vit B6

51
Q

How can Vit A deficiency affect immune function

A

interferes with epithelial cell function and the ability of certain immune cells to kill organisms, production of B and T cells are dependent on Vit A

52
Q

How can Vit C deficiency affect immune funtion

A

decrease in collagen synthesis, phagocyte oxidative burst activity impaired, b and T cells don’t work properly

53
Q

How can Vit B12 def, affect immune funtion

A

it lowers T cell count and NK cell activity

54
Q

How can Vit B6 def affect immune function?

A

decrease T cell responsiveness and NK ability to kill organisms

55
Q

Generally speaking what are the immune disfunction associated with malnutrition?

A

The # of circulating T cells declines, while % of NK cells rises.

Serum Ig’s is normal or increased, however, Ab response is impaired.

Primary and secondary lymphoid organs are depleted of cells and lymphoid follicles are sparse.

Decreased phagocytic activity

56
Q

How can viruses affect immune function?

A
  1. immunosuppression can result from direct effects of viral replication on lymphocyte function
  2. A virus can infect cells to produce soluble factors that suppress immune function.
  3. Viral infection of macrophages causes them not to work correctly so they can’t function acquired or innate immunity
  4. Viral infection of a suppressor cell can result in an inappropriate immune response.
57
Q

What are some strategies that bacteria use to avoid our acquired immunity?

A

molecular mimicry
suppression of antibodies
hiding inside cells
releasing Ag into bloodstream

58
Q

What are strategies bacteria use against being phagocytized

A

inhibit chemotaxis
inhibit phagocytosis
killing phagocyte
colonizing the phagocyte

59
Q

How does HIV suppress immune function?

A

It selectively attacks CD4’s as well as macrophages and dendritic cells

60
Q

How does Measles suppress immune function?

A

T-cell lymphopenia

Diminished ab production caused by direct infection of T-cells by measle virus, and infection of dendritic cells.

61
Q

How can parasites suppress immune function?

A

alteration of macrophage function, induction of suppressor T cells, production of immunosuppressor factors by parasites. Malaria is an example where infection with EBV leads to Burkett’s lymphoma.

62
Q

How can cancer suppress immune function?

A

Tumors can undermine normal immune regulation

Also immune deficiency secondary to chemotherapy, radiation Rx and cancer itself.

63
Q

How does chronic lymphocytic leukemia affect immune function?

A

asdfasdf

64
Q

How does multiple myeloma affect immune function?

A

CD4 deficit, decrease in complement and neutrophil function.

65
Q

How do solid tumors affect immunological function?

A

They inhibit function of normal lymphocytes and increase suppressor lymph activity. It is a decrease in peripheral t-cell lymphocytes, usually Ab responses are spared.

66
Q

How does renal disease impair immune function?

A

When it progresses to nephrotic syndrome:
1. major proteinuria
2. hypoalbuminemia
3. hyperlipidemia
4. edema
With loss of protein you get hypogammaglobulinemia of IgG, IgM and IgE.

Dialysis:
You have reduced T-cell function, also diminished Ab production and neutrophil function

Renal patients are often on glucocorticoids. These tend to suppress phagocytosis, decrease circulating T-cells, inhibits IL-2 cytokines

67
Q

What is sarcoidosis?

A

This is a multi-system disorder with unknown ideology. It i characterized by: accumulation of T cells, mononuclear phagocytes, and pulmonary granulomas.

68
Q

How does sarcoidosis impair immunity?

A

Peripheral T cell lymphopenia, decreased CD4 T-cells, hypergammaglobulinemia, sarcoid granulomas made up of CD4 T cells, periphery combo of CD4 and CD8 cells.

69
Q

How are transplant patients immunosuppressed?

A

By medications: including:

corticosteroids, macrolides, and antimetabolites.

70
Q

Why are diabetes patients immunocompromised?

A

Hyperglycemia reduces neutrophil function resulting in fungal infection. Poor circulation leads to skin ulceration as well as a diminished delivery of neutrophils to the site.

Immunology (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions