Brainscape's Knowledge GenomeTM

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


See full index

Pathology > Chapter 6- Diseases Of The Immune System > Flashcards

Chapter 6- Diseases Of The Immune System Flashcards

1
Q

What are the characteristics of innate immunity?

A

Elements are always present, ready to react before infections occur

No antigen specificity or memory

First line of defence

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

What are some elements of innate immunity?

A

Epithelial barriers

Phagocytes

NK cells

Complement

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

What are the characteristics of adaptive immunity?

A

Mechanisms stimulated by foreign substances

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

What makes up adaptive immunity?

A

Lymphocytes and their products

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

What are the two components of adaptive immunity?

A

Humoral (B cells)

Cell mediated (T cells)

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

What type of antigenic stimuli does each form of adaptive immunity protect against?

A

Humoral- extracellular, toxins

Cell mediated- intracellular

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

What is the most common APC?

A

Dendritic cells

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

What are the different immune cells and their functions?

A

B lymphs- Ab production

TH/CD4- recognizes Ag bound to APC, mac and lymph activation

TC/CD8- recognizes Ag on infected cells, kills cells

Treg- immune suppression

NK- kills infected cells

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

What tissues are involved in the production, maturation and storage of immune cells?

A

Generative lymphoid organs- BM and thymus

Peripheral lymphoid organs

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

What is a hypersensitivity reaction?

A

Excessive response to an Ag

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

What genes are often associated with hypersensitivity reactions?

A

Susceptibility genes (HLA/MHC)

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

What are the categories of hypersensitivity reactions?

A

Type I/immediate

Type II/Ab mediated

Type III/immune complex mediated

Type IV/T cell mediated

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

What are the characteristics of Type I hypersensitivity reactions?

A

Allergies

TH2 cells stimulate IgE production

IgE binds mast cells and releases histamine

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

What are the phases of Type I hypersensitivity reactions?

A

Immediate reaction- histamine release causes vasodilation, vessel permeability, etc

Second/delayed phase- eosinophils infiltrate tissues causing damage

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

What is systemic anaphylaxis?

A

Hypotensive shock associated with allergies (Type I)

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

What are the characteristics of Type II hypersensitivity reactions?

A

Abs on cell surfaces or ECM activate immune cells and lead to damage

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

What causes the pathology of Type II hypersensitivity reactions?

A

Opsonization and phagocytosis destroy cells

Inflammation

Complement activation

Cellular dysfunction

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

What diseases are caused by Type II hypersensitivity reactions? What are their characteristics?

A

Myasthenia gravis- Ab blocks ACh binding

Grave’s disease- Ab stimulates TSH receptor

Goodpasture’s disease- Ab causes tissue damage

AIHA- Ab binds RBCs, cells are lysed/cleared

Rh HDN- Ab binds and cells are lysed/cleared

ITP- Ab against platelets causes their destruction

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

What are the characteristics of Type III hypersensitivity reactions?

A

Ag-Ab complexes elicit inflammation at sites of deposition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What organs are involved in Type III hypersensitivity reactions?

A

Kidneys

Joints

Blood vessels

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

What are the phases of Type III hypersensitivity reactions?

A

Formation (1 week)

Deposition

Inflammation and tissue injury (10 days)

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

What diseases are associated with Type III hypersensitivity reactions? What are their characteristics?

A

SLE- deposition in kidney

Glomerulonephritis- deposition in glomerular BM

Polyarteritis- Hep B Ag causes systemic vasculitis

Reactive arthritis- bacterial Ags

Serum sickness- foreign protein causes arthritis, vasculitis, nephritis

Arthus reaction- localized necrosis, from vasculitis (large complexes ppt)

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

What are the characteristics of Type IV hypersensitivity reactions?

A

Stimulation of T cells leads to tissue injury

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

What test is prototypical of Type IV hypersensitivity reactions?

A

Mantoux/tuberculin test

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

What cells are involved in Type IV hypersensitivity reactions and how do they function?

A

CD4- produce inflammatory cytokines (tissue damage)

CD8- kill viral infected cells

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

What are the characteristics of autoimmune diseases?

A

Reactions against self Ags

Breakdown in self tolerance

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

What are the two kinds of tolerance and where do they occur?

A
  1. Central- BM and thymus

2. Peripheral- peripheral tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

How does tolerance occur?

A

Central- T and B cells that are self reactive are killed/inactivated

Peripheral- self reactive lymphs are inactivated (anergy), suppressed or killed

29
Q

What cell suppressed self reactive lymphs?

A

Tregs

30
Q

What factors can lead to disruption of tolerance?

A

HLA genes

Defective tolerance

Abnormal self Ag displays

Inflammation

31
Q

How may infections cause autoimmune reactions?

A

Upregulation of a costimulator

Molecular mimicry

Injury leads to release of cryptic self Ags (no tolerance)

Alteration of self Ag

32
Q

What is molecular mimicry?

A

Microbes express Ags similar to self Ags and Abs cross react

33
Q

What are the common autoimmune diseases?

A

SLE

Sjögren syndrome

Scleroderma/systemic sclerosis

Mixed connective tissue disease

Transplant rejection

34
Q

What are the characteristics of SLE?

A

Systemic disease involving ANAs

Can affect all organs

35
Q

How does tissue injury occur in SLE?

A

Immune complex deposition (Type III)

Ab mediated actions (Type II)

36
Q

How does SLE affect various organ systems?

A

Vessels- necrotizing vasculitis

Kidney- lupus nephritis

Skin- butterfly rash, erythema

Spleen- splenomegaly, capsular thickening

Lungs- pleuritis and effusions, fibrosis, hypertension

Serosal cavity- fibrinous exudate, effusions

Cardiovascular- valve thickening (mitral and aortic), peri and myocarditis

37
Q

What type of vegetations are associated with SLE?

A

Libman-Sacks/nonbacterial verrucous endocarditis

On mitral and tricuspid

38
Q

What are the characteristics of Sjögren syndrome?

A

Immune mediated salivary and lacrimal gland destruction

Dry eyes (keratoconjunctivitis) and mouth (xerostomia)

39
Q

How is Sjögren syndrome diagnosed?

A

Lip biopsy

40
Q

What are patients with Sjögren syndrome at risk for?

A

B cell lymphoma

41
Q

What are the characteristics of scleroderma?

A

Chronic inflammation

Small vessel damage

Interstitial and perivascular fibrosis (skin, GI tract)

Claw-like fingers (autoamputation), drawn mask-like face

42
Q

What types of scleroderma are there and what are their characteristics?

A

Diffuse- widespread skin involvement, early visceral involvement

Limited- late visceral involvement

43
Q

Mixed connective tissue disease includes features of what disorders?

A

SLE

Scleroderma

Polymyositis

44
Q

Why does graft rejection occur?

A

The immune system recognizes the graft as foreign

Triggered by foreign HLA histocompatibility molecules

45
Q

What are the two classes of HLA molecules? What cells are they present on and what cells are they recognized by?

A

Class I- on all uncleared cells, CD8 recognition

Class II- on APC, CD4 recognition

46
Q

What are the two pathways of graft rejection?

A

Direct- donor APC activates host T cells

Indirect- host APC presents donor Ag to T cells

47
Q

What are the three types of graft rejection? What are their characteristics?

A
  1. Hyperacute- previously sensitized, occurs in minutes to days, cyanotic/mottled organ
  2. Acute- newly synthesized Abs, occurs in days to months, causes necrotizing vasculitis
  3. Chronic- progressive dysfunction, occurs in months to years, allograft ischemic, immune suppression
48
Q

What is graft vs host disease?

A

Donor lymphs (BM transplant) recognize host cells as foreign

T cell injury

49
Q

What host components are most affected by GVHD?

A

Immune cells

Biliary epithelium

Skin

GI tract

50
Q

How is infection differentiated from GVHD?

A

Biopsy

51
Q

What types of immunodeficiency syndromes are there?

A

Primary/congenital

Acquired/secondary

52
Q

What are the characteristics of primary immunodeficiencies?

A

Genetically determined

Detected early (6mo-2yr)

Affects innate immunity and cellular components of adaptive immunity

53
Q

Why are primary immunodeficiencies detected at 6mo?

A

Mom provides IgA (breastfeeding, drop off from in utero)

54
Q

What are the common primary immunodeficiencies? What are their characteristics?

A

Defects in leukocyte function

Defects in complement

Severe combined immunodeficiency- defects in both immune responses

X-linked/Bruton’s aggamaglobulinemia- no serum Ig

Common variable immunodeficiency- hypogammaglobulinemia

Isolated IgA deficiency- mucosal immunity affected

Hyper IgM syndrome- no other Ig, can react with blood cells

DiGeorge syndrome- thymic and parathyroid hyperplasia

55
Q

What are common defects in leukocyte function?

A

Adhesion defects

Phagylosome function defect (Chediak-Higashi)

Microbicidal activity defect

Defect in TLR signalling (recognition)

56
Q

What deletion is common in DiGeorge syndrome?

A

22q11

57
Q

What type of immunodeficiency is more common?

A

Secondary

58
Q

What are common acquired immunodeficiency disorders? What are their characteristics?

A

HIV- CD4 depletion

Cancer therapy- BM precursor depletion

BM cancers- reduced leukocyte production

Malnutrition- maturation and function inhibited

Splenectomy- reduced microbial phagocytosis

59
Q

What are the characteristics of AIDS?

A

Immunodeficiency retrovirus

T cell suppression (CD4)- inactivation and death

Opportunistic infections

Tumours

CNS disease

60
Q

What are the phases of HIV?

A
  1. Primary infection- virus dissemination
  2. Chronic infection- latency
  3. AIDS
61
Q

What tumours are associated with AIDS?

A

Kaposi sarcoma- vascular, HHV8/KSHV

Lymphoma- B cell NHL

Squamous cell (HPV)

62
Q

What infection increases the likelihood of CNS lymphomas in AIDS?

A

EBV

63
Q

What are the characteristics of amyloidosis?

A

Extracellular deposits of fibrillation proteins result in damage and dysfunction

Aggregations of insoluble misfolded proteins

64
Q

How are proteins in amyloidosis misfolded?

A

Beta pleated sheets

65
Q

What stain is used for amyloidosis and what does it look like?

A

Congo red

Apple green birefringence with polarized light (red/pink with light mic)

66
Q

What are the forms of amyloidosis?

A
  1. Amyloid light chain (plasma cells)
  2. Amyloid associated (chronic inflammation)
  3. Beta amyloid (Alzheimer’s)
67
Q

What are different amyloidosis disorders?

A

Primary- immunocyte dyscrasias with amyloidosis (light chain, tumour secreted)

Secondary reactive- chronic inflammation

Hemodialysis associated (60-80% of patients)

Heredofamilial amyloidosis (familial Mediterranean fever)

Localized- endocrine and aging

68
Q

What is the morphology of amyloidosis?

A

Enlarged, waxy, form tissues

Kidneys- glomerular hyalinization, tubular deposits, atrial wall thickening

Sago spleen- tapioca granules in white pulp (follicles)

Lardaceous spleen- red pulp deposits

Hepatomegaly

Heart- subendocardial droplets

Macroglossia

Carpal tunnel syndrome

69
Q

What are the favoured biopsy sites for amyloidosis?

A

Kidney rectum

Gingiva

Abdominal fat pad (reduced sensitivity)

Pathology (25 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions