Immunodeficiencies Flashcards
(125 cards)
1
Q
Primary Immunodeficiencies:
A
Genetic mutation that may occur at any phase of the immune response [from danger recognition (TLRs) to synthesis of high affinity antibody (tetanus specific antibody)].
2
Q
What are the most common types of Primary Immune Deficiencies (PID):
A
Antibody Deficiencies
3
Q
Signs / Symptoms of Humoral Immunodeficiency:
A
- Pyogenic Infections (recurrent otitis media, sinusitis, pneumonia; cellulitis, osetomyelitis, meningitis); 2. Frequent viral infections; 3. Chronic diarrhea
4
Q
How many infections are too many?
A
- More than 4 courses of antibiotics per year in children
- More that 2 courses of antibiotics per year in adults.
- More than 4 new ear infections in one year after age four.
- Pneumonia twice over any time.
- More than 3 episodes of bacterial sinusitis in one year or the occurrence of chronic sinusitis.
5
Q
Agammaglobulinemias are caused by defects in WHAT
A
B Cell development
6
Q
Formation of WHAT is defective in Agammaglobulinemia?
A
Germinal Center formation; associated with underdevelopment of lymphoid tissues, such as the lymph nodes, Peyer’s patches, spleen, tonsils and adenoids.
7
Q
________ accounts for 85% of all agammaglobulinemias
A
X-linked agammaglobulinemia, also known as Bruton’s agammaglobulinemia
8
Q
Boys or lyonized females with this condition have a defect in _______
A
B cell tyrosine kinase (BTK)
9
Q
What is BTK?
A
BTK is associated with the pre-B cell receptor and is required for transducing signals from the pre-B cell receptor downstream that simulates B cell maturation.
Pre-B cell needs this enzyme to function for B cells to mature. Without it, can’t have mature B cells, no antibody production, etc.
Minor defects of other areas in this pathway can cause similar defects but generally less severe.
10
Q
Describe the blood test results standard for a patient with X-linked Agammaglobulinemia:
A
- IgG usually <100 mg/dl
- B cells <2% of lymphocytes (usually 0.05-0.3%)
- Normal T cell number and function
11
Q
Hyper IgM Syndromes:
A
- Defects in B cell isotype switching collectively lead to a group of disorders called the Hyper-IgM (HIGM) syndromes.
- Normal numbers of B cells, but express elevated levels of IgM with low IgG, IgE, and IgA.
12
Q
IgA Deficiency:
A
Sometimes called “Selective IgA Deficiency”
Often asymptomatic.If you are symptomatic, might have recurrent diarrhea or autoimmune disease.
Only a subset of these people have NO IgA.
13
Q
What are the blood test results of IgA Deficiency?
A
IgA <5-7 mg/dl
14
Q
For patients with a severe IgA deficiency, why might there be a problem with administering IVIG?
A
F you have no IgA, this means you can produce antibodies against IgA, which can be bad and cause anaphylaxis.
Before giving any patients IVIG, should check IgA levels.
Usually the first dose of IVIG is in the hospital for any patient in case there is a reaction.
15
Q
CVID (Common Variable Immunodeficiency):
A
Second most frequent PID in humans after IgA deficiency. Most prevalent PID in adults.
Characterized by recurrent infections (sinusitis most common, followed by pneumonia; life threatening infections)
16
Q
What types of disorders are associated with CVID?
A
Granulomatous diseases, autoimmune disorders, splenomegaly, and certain malignancies (300x lymphoma risk of general population)
17
Q
What are the serum levels of patients with CVID?
A
- Reduced serum IgG, IgA and/or IgM
- Absent or impaired specific antibody responses to previous infection or vaccination
18
Q
What are the causes of CVID?
A
Unknown; causes of CVID have remained elusive with the genetic basis identified in less than a quarter of cases.
19
Q
Specific Antibody Deficiency is characterized by what types of infections?
A
Recurrent sinopulmonary infections
20
Q
What are the serum levels of Specific Antibody Deficiency patients?
A
Normal IgG, IgA, and IgM
Normal B cell number and normal T cell number and function
Impaired vaccine response
21
Q
What is impaired in patients with Specific Antibody Deficiency?
A
- Impaired vaccine response (polysaccharide)
- Impaired antibody response to natural infection with encapsulated bacteria
22
Q
How might you test to determine if a patient has CVID?
A
Check tetanus titer (or something everyone is vaccinated with) - if zero or very low, the patient haven’t been able to mount an antibody response
23
Q
What is the mnemonic for encapsulated organisms?
A
Some Killers have Pretty Nice Capsules;
- Streptococcus pneumoniae & pyogenes
- Staph aureus
- Klebsiella
- Haemophilus influenzae
- Pseudomonas aeruginosa
- Neisseria meningitidis
- Cryptococcus neoformans
–Mycoplasma
–Bordetella pertussis
–some E. coli
–Streptococcus agalactiae
–Yersinia pestis (F1 envelope)
24
Q
Transient Hypogammaglobulinemia of Infancy:
A
Thought that in this case there is a delayed T cell maturation to help with priming/stimulating B cells to produce enough antibody. Onset around 6 months of age. Generally resolved around age 4.
Characterized by recurrent sinopulmonary infections.
25
What are the serum levels of patients with Transient Hypogammaglobulinemia of Infancy?
* Low IgG, but
* Normal specific antibodies
* Normal lymphocyte number and function
26
What diagnostic evaluation should be done to evaluate humoral immune system function?
* CBC with differential (Make sure lymphocyte count adjusted for age)
* Age-adjusted quantitative immunoglobulins
* Specific Antibody Titers
* Complement pathway (functional assays; CH50, AH50, MBL - rare, but seen in CF patients)
* Lymphocyte Markers (with CBC with diff)
–CD19 (B cell)
27
How do you test for specific antibody production?
•Check protein sonstituents
–Diphtheria, Tetanus
–Tetanus \>0.15 protective
•Polysaccharides
–Isohemagglutinins (ABO), need to check blood type first
28
What antibody level of tetanus is protective?
\>0.15 protective
29
What level of pneumococcal response is protective?
1.3 mcg/mL
30
What rise in titer serotype is considered an adequate response after a booster?
\>4 fold rise in titer
31
Pneumovax:
An old polysaccharide vaccine
32
Prevnar:
Newer conjugated vaccines (polysaccharide coupled with a protein) - has a lot more serotypes than Pneumovax and this has helped reduce a lot of infection. (Vaccines can help with antibiotic resistance).
33
Lack of T cells will result in \_\_\_\_\_\_. Patients with T-cell primary immunodeficiency disorders are susceptible to \_\_\_\_\_\_\_
Lack of T cells will result in COMBINED IMMUNODEFICIENCIES. Patients with T-cell primary immunodeficiency disorders are susceptible to OPPORTUNISTIC and INTRACELLULAR MICROORGANISMS.
34
What types of infections are people with T cell dysfunction prone to?
Infections with intracellular microorganisms:
* Viruses (HSV, V-Z, CMV, EBV)
* Protozoa (Cryptosporidium, toxoplasma)
* Mycobacteria
* Fungal (Candida, Pneumocystis jiroveci)
* Bacteria, gram negative enteric (T-cell)
* Bacteria, polysaccharide encapsulated (B-cell)
35
What are Clinical Characteristics of patients with T cell dysfunction?
* Failure to thrive (especially with diarrhea)
* Anergy to recall antigens
* Graft versus host disease (can manifest as eczematous rash)
–Mother’s T cells attacking the child’s skin
* Increased B-cell malignancies
* Eosinophilia, thrombocytopenia
* Eczema, alopecia
* Thrush
36
SCID:
See problems early on, impacting B cells, T cells, NK cells.
Sometimes as a result of adenosine deaminase deficiency. Get a defect in all 3 cell lines. There is an enzyme replacement for this particular deficiency.
Most common is X-linked SCID, which gives problems with T and NK, but not really B.
RAG deficiency is where you hit B and T cells, but not really NK cells. For these need to talk about stem cell transplant, these are often fatal.
37
Characteristics of Omenn Syndrome:
* Hypomorphic mutations, most commonly in RAG genes
* Low to normal number of T cells…but oligoclonal T cell population
* Early onset (\< 3 months) of a diffuse, exudative erythroderma
* Lymphadenopathy
* Hepatosplenomegaly
* Chronic persistent diarrhea
* Failure to thrive
* Elevated IgE and Eosinophilia
–This can be confused for otherwise normal baby with eczema
•Considered a “Leaky” SCID
38
What is the genetic basis of DiGeorge Syndrome:
Defect in embryogenesis (3rd and 4th pharyngeal pouches). The structures that arise from these areas include facies, parathyroid, thymus, and aortic arch. Most have a deletion of chromosome 22q11.2.
Sporadic, affecting both males and females.
39
What are the clinical features of DiGeorge Syndrome?
–Dysmorphic facies (micrognathia, low set ears)
–Hypocalcemia (lack of parathyroids)
–Can have depressed T-cell immunity (hypoplastic to aplastic thymus)
–Congenital heart disease (aortic arch defects, VSD)
40
How is DiGeorge Syndrome diagnosed?
Diagnosed immediately by lateral chest x-ray (absence of thymic shadow)
41
How do DiGeorge patients present within the first few days of life?
This immunodeficiency presents in the first few days of life not with infections, but with hypocalcemic seizures or congenital heart disease.
42
Partial vs. Complete DiGeorge:
**Partial:** most frequent, thymic hypoplasia (normal corticomedullary differentation, presence of Hassall's corpuscles) BUT normal thymic function. CD4 \> 400/mm^3, T cell function adequate, B cell numbers and function normal, usually free of infections
**Complete:** uncommon, thymic aplasia, CD4 cells \< 400/mm^3, B cell numbers normal, antibody response decreased, susceptible to infections, susceptible to GVHD
43
Complete DGA has CD3+ T-cells \< \_\_\_% and requires T-cell immune reconstitution. How does this compare to Partial DGA?
Complete DGA has LYMPHOPENIA and CD3+ T-cells \< 5% and requires T-cell immune reconstitution. In partial DGA, CD3+ T-cells may be moderately depressed or normal. Certain congenital cardiac disorders have a high association with DGA, such as interrupted aortic arch and truncus arteriosus.
44
Lymphopenia:
An abnormally low level of lymphocytes in the blood
45
Describe the presentation of patients with Wiskott Aldrich Syndrome:
–Eczema
–Thrombocytopenia with small platelets (look for low MPV)
–Immunodeficiency
46
The Wiskott Aldrich Syndrome Protein (WASP) is involved with \_\_\_\_\_?
Actin polymerization; thought to affect various lymphocyte functions
47
What diagnostic evaluations should be completed for patients suspected of having combined immunodeficiencies?
[Humoral immunity will be impaired in combined immunodeficiencies]
## Footnote
* CBC with differential
* Age-adjusted quantitative immunoglobulins
* Specific Antibody Titers
–Protein vaccines
–Polysaccharide vaccines
48
CD19:
Lymphocyte marker for B cells
49
What markers are used to find T cells in CBC with diff?
CD 3 (Total T cells), CD4 (Helper T cells), CD8 (Cytotoxic T cells)
50
What markers are found on NK Cells?
CD16/56
51
How can T cells be tested to determine function/presence?
* Lymphocyte Markers (get these with CBC with diff)
* Lymphocyte mitogen proliferation assays
* Antigen reactivity (Candida, tetanus)
* DTH to Candida
* Nucleic acid enzyme assays (Adenosine Deaminase)
52
Lymphocyte mitogen proliferative assays:
–nonspecific mitogens phytohemagglutinin (PHA)
- concanavalin A (Con A), and
- pokeweed (determined by 3H-thymidine incorporation)
53
Name 4 important diseases caused by defects in Innate Immunity:
* Chronic Granulomatous Disease
* Leukocyte Adhesion Deficiency
* HyperIgE Syndrome
* Complement Disorders
54
CGD is characterized by what kinds of infections?
Recurrent bacterial infections with catalase positive organisms (Staph, Serratia; also Aspergillus).
-Pathognomonic organism (chromobacteriam violaceum)
55
What physical characteristics are associated with CGD?
* Granulomas of skin, liver, lungs, lymph nodes
* Phagocytic cells ingest but do not kill bacteria due to failure to form oxygen radicals
56
How is CGD disgnosed?
Diagnosed by:
1. Nitroblue tetrazolium dye test
2. Superoxide radical formation (chemiluminescence test)
3. Flow cytometry (dihydrorhodamine 123 assay)
Measures change in fluorescence of DHR loaded granulocytes after PMA stimulation
57
Leukocyte Adhesion Deficiency-1 is characterized by the absence of WHAT?
Absent beta subunit (CD18) of 3 cell surface glycoproteins (CD11 family)
–β2 integrins
58
Neutrophils can't migrate towards inflammatory stimuli or adhere to vascular endothelium in WHAT disease?
Leukocyte Adhesion Deficiency-1
59
How is Leukocyte Adhesion Deficiency-1 diagnosed?
–Recurrent soft tissue infections
–Delayed umbilical cord separation
–Severe periodontal disease
–No pus formation despite high white blood cell counts
60
Describe the characteristics of Hyper IgE Syndrome (aka Job Syndrome)?
* Recurrent staphylococcal abscesses (cold abscesses), sinopulmonary infections, and severe eczema
* Retained primary teeth
* Recurrent Candida
* Recurrent bone fractures
61
What are the serum characteristics of Hyper IgE syndrome?
Very elevated IgE level - usually \>2000.
Peripheral eosinophilia
62
How many components of the classical pathway are required for a normal CH50 value of \_\_\_\_?
All nine components of the classical pathway (C1-C9); normal CH50 value is 150 to 250 units/mL
63
What does a CH50 value of 200 units/mL mean?
A CH50 of 200 units/mL means that a serum sample diluted 1:200 lysed 50 percent of the antibody-coated sheep erythrocytes in the test mixture. [This is a normal value]
64
AH50 Assay Method:
EGTA is added to serum. EGTA chelates Ca2+ required for the assembly of the C1 macromolecule of complement, thereby inhibiting activity of the classical pathway.
65
Heterozygous deficient individuals will generally have a ______ CH50, (explain).
Heterozygous deficient individuals will generally have a normal CH50, because the level of a component must be reduced by more than 50 percent before the CH50 is altered.
66
A complete deficiency of one component gives WHAT CH50 value
A complete deficiency of any one component gives an undetectable CH50 value.
67
Defects in _____ lead to Hereditary Angioedema.
C1 Esterase Inhibitor
68
Diagnostic tests in the diagnosis of defects in innate immunity:
* Complete Blood Count with Differential
* Neutrophil function
–Assays for Oxidative Burst (including flow cytometry), Chemotaxis assays, Leukocyte phenotypes
* presence of CD18 β integrin
* Assays for Complement
69
What primary immunodeficiency diseases are diagnosed within birth to 3 months?
–Phagocytic cell defects
–Complement defects
–DiGeorge syndrome
70
What primary immunodeficiency is diagnosed between 3-6 months of age?
Severe Combined Immunodeficiency (SCID)
71
What primary immunodeficiency is diagnosed from 6-18 months of age?
x-linked agammaglobulinemia (transient hypogam)
72
What primary immunodeficiency is diagnosed between 18 months to adulthood?
- Common variable immunodeficiency
- Complement defects
73
What physical exam findings are important in the diagnosis of primary immunodeficiencies?
* Growth measurements
* Inspection of tonsils
* Thrush?
* Palpation of lymph nodes
* Organomegaly
* Skin lesions (eczematous, mycobacterial)
[Particular attention should be paid to evaluation of lymph node and tonsillar tissue, growth parameters, and skin rashes. All may be abnormal due to a primary defect in immunity.]
74
How are humoral/antibody deficiencies treated?
* Avoidance of high rate exposure to infection
* Antibiotic therapy/prophylactic antibiotics (Daily amoxicillin at 20 mg/kg/day, augmentin, or bactrim)
* IgA deficiency, Specific antibody deficiency, Transient hypogammaglobulinemia
* IV (Intravenous) or SQ (Subcutaneous) IgG
75
Describe the differences between IV or SQ (subcutaneous) IgG:
–Administer IVIG every 3-4 weeks for Agammaglobulinemia, some Hyper IgM syndromes (AID & UNG), CVID
–Administer SQIgG weekly (but can be done at home) - examples include Hizentra or Gammagard
76
How are combined immunodeficiency disorders treated?
* Stem cell transplantation
* Enzyme replacement (PEG-ADA)
* Thymic transplant for DiGeorge
* Gene therapy (ADA, XL-SCID)
* IVIG (not a cure, need continuously)
* Avoidance live viral vaccines
* Irradiation blood products
* Prophylactic antibiotics
77
Decribe the treatment for defects of phagocytic cells:
* Prophylactic antibiotics
* Avoidance of live viral vaccines in some patients
* Gamma interferon in chronic granulomatous disease
* Bone marrow transplantation in some patients
[Treatment for defects in the phagocytic system are largely supportive. Some, however, provide sophisticated treatment to a select few patients (e.g. gamma interferon in chronic granulomatous disease)].
78
Describe the treatments for complement immunodeficiency:
* Symptomatic care
* Frequent use of antibiotics
* Immunizations with bacterial polysaccharide vaccines, (e.g. Pneumococcal vaccines)
79
Acquired Immunodeficiencies:
* Defects in the immune system not arising from genetic abnormalities, but from infections, nutritional deficiencies, other medical conditions or treatments, or external stimuli.
* The consequences of these mutations lead to undue susceptibility to infection, autoimmunity, and / or malignancy.
80
If the etiology of the defect is a genetic abnormality it is termed a(n) _______ immunodeficiency.
primary immunodeficiency
81
Major etiologies of acquired immunodeficiency include:
1. Disorders of biochemical homeostasis (diabetes, dialysis / uremia, cirrhosis)
2. Disorders of protein loss (nephrotic syndrome, dialysis, protein losing enteropathies)
3. Trauma / burns
4. Environmental exposures (radiation, chemical)
5. Splenectomy / hyposplenism
6. Life events (pregnancy, stress)
7. Infections (in addition to HIV)
82
83
Disorders of Biochemica Homeostasis:
* Disorders leading to chronic imbalance in hormones, nutrients, and toxic metabolic waste products in body fluids.
* May have significant effects on the function of one or more components of the immune system.
84
Give 3 common examples of disorders of biochemical homeostasis:
–Diabetes mellitus
–Dialysis and uremia
–Cirrhosis
85
Diabetes mellitus is characterized by decreased ____ function and poor \_\_\_\_\_\_\_.
- Decreased neutrophil function (directly related to the level of hyperglycemia)
- Poor peripheral circulation (increases risk of skin ulceration, decreased delivery of neutrophils to sites)
86
The usual infectious complications of diabetes include disseminated \_\_\_\_\_\_\_
candidiasis yeast and other fungi
87
What are the two types of dialysis?
Hemodialysis
CAPD (Chronic Ambulatory Peritoneal Dialysis)
88
Problems associated with hemodialysis:
Results in reduced T cell function & Ig production, compromised neutrophil and dendritic function.
Some defects due to high endogenous glucocorticoid and cytokine levels.
89
Problems associated with CAPD:
No significant systemic immune defects, but do see changes in peritoneum.
•Peritoneal neutrophil function depressed due to removal of opsonic factors (immunoglobulin and complement) with the dialysate.
90
Cirrhosis characteristics:
–Liver dysfunction - greater risk of bacterial sepsis and peritonitis
–Etiology: higher endogenous glucocorticoids & low complement levels (complement made in liver).
91
Cirrhosis is characterized by higher levels of ______ and low \_\_\_\_\_\_.
- Higher endogenous glucocorticoids
- Low complement levels (complement is made in liver)
92
What are some common mechanisms/disorders of protein loss?
* Nephrotic syndrome (loss through kidneys / urine)
* Protein losing enteropathies (loss through GI tract / stool)
* Severe dermatitis (loss through skin)
* Peritoneal dialysis (in this category also)
93
Any disease process with increased protein loss can lead to:
Hypogammaglobulinemia
- Often present as low IgG and IgA, sometimes near normal IgM (because these are large and don't pass through kidney easily)
- Antibody levels present in low titer, patient may not have increased susceptibility to infection
94
How would you determine if IgG levels are low due to protein loss vs low B cells / decreased production, etc.?
The half-life of IVIG is well-known. If you see a big loss of immunoglobulins via e.g. the gut, the IVIG would lower in the body much faster than the normal half life would degrade it.
95
Nephrotic syndrome is a form of kidney disease with \_\_\_\_\_
Significant protein loss, resulting in low IgGs (may be severe) and depressed cellular immunity due to loss of vitamin D and other serum factors
96
How is nephrotic syndrome treated?
Treated with immunosuppressive drugs (e.g. glucocorticoids), which further increases the risk of infection
97
Infectious complications of nephrotic syndrome:
Recurrent respiratory tract infections, urinary tract infections, peritonitis, and sepsis, particularly with encapsulated bacteria such as Streptococcus pneumonia.
Varicella (chicken pox) problematic in patients requiring immunosuppression.
98
In addition to biochemical homeostasis issues, patients can have protein loss if on _____ dialysis for chronic renal disease leading to low \_\_\_\_.
In addition to biochemical homeostasis issues, patients can have protein loss if on PERITONEAL dialysis for chronic renal disease leading to low Ig.
99
\_\_\_\_\_\_\_\_\_\_\_ include inflammatory bowel disease, celiac disease, and intestinal lymphangiectasia. All these disorders can lead to significant ______ through the GI tract.
PROTEIN-LOSING ENTEROPATHIES include inflammatory bowel disease, celiac disease, and intestinal lymphangiectasia. All these disorders can lead to significant PROTEIN LOSS through the GI tract.
100
Patients with recurrent infections and low serum IgG may benefit from _________ infusions; however, relatively large doses may be required due to ongoing intestinal loss. Replacement therapy in this setting remains controversial.
Gamma globulin infusions
101
Mechanism initiating cascade of immune effects is massive release of _____ cytokines (interleukin-1, tumor necrosis factor) due to widespread activation of _____ and _______ by the products of cellular necrosis
inflammatory cytokines
monocytes and macrophages
102
Burn trauma causes ______ immune suppression than mechanical trauma
greater
103
Environmental Exposures resulting in acquired immunity:
* Ionizing radiation
* UV radiation
* Toxic chemicals
104
Ionizing Radiation:
* X-rays, gamma rays
* Damages DNA --\> impaired cell division & somatic mutations may be expressed --\> impaired immune function (like chemotherapeutic agents)
* May induce apoptosis (programmed cell death) in susceptible lymphocytes
* Somatic mutations may impair function of cellular proteins that regulate cell division (eg, the p53 tumor suppressor gene), lead to malignant cell growth
105
Ionizing radiation leads to dose-dependent decline in peripheral blood lymphocyte counts (explain):
–affects B cells more than T cells
–Tissue (nodes, spleen) affected, impacts lymphocyte homing and recirculation
–T cell numbers recover more rapidly than B cells
–Primary antibody responses diminished
–Most functions of mature, long-lived phagocytic cells (macrophage) relatively radiation-resistant
106
Increased susceptibility to infection by ionizing radiation is also due to ______ (explain):
Damaged local barriers
e.g. areas with high rates of cellular division (gut\>skin)
107
\_\_\_\_\_\_ radiation via sun exposure is the major determinant of risk for skin cancer
Ultraviolet B
108
Chronic sun exposure leads to diminished function of \_\_\_\_\_
all skin resident immune cells
109
Toxic chemicals and immunity:
•Numerous environmental chemicals incriminated in causing harm to the immune system
–(given rise to the discipline of immunotoxicology)
•Accumulated experience supports the importance of environmental chemical exposure for immune system dysfunction
110
Etiology of Spelenectomy/Hyposplenism:
–Congenital asplenia
–Trauma or status post splenectomy
–Atrophy / non-functional spleen
* Atrophy – e.g. sickle cell disease
* Functional asplenia – e.g. autoimmune disease, severe celiac disease, inflammatory bowel disease, chronic graft-versus-host disease, untreated HIV infection
111
Not having a spleen puts patients at risk of sepsis with _____ organisms. How is this managed?
Encapsulated organisms (can be fatal, children\>adults)
Management: immunization (prior to splenectomy if possible) plus consideration of antibiotic prophylaxis
112
During pregnancy, have a higher incidence of certain infections dependent upon ____ immunity for their control (explain).
Cellular immunity;
e.g. Hepatitis A and B, influenza, herpesviruses, chlamydia, listeria, Campylobacter, tuberculosis, and several fungal, protozoan, and helminthic infections
113
Why is there a decrease in cellular immunity during pregnancy?
"survival benefit" by reducing the likelihood of maternal "rejection" of the fetus which contains potent alloantigenic stimuli derived from the father. (Multiple factors implicated in the immune alterations).
114
Diminished _____ immune function has been described in PTSD
cellular
115
Broadly, reduced _____ activity and depressed _____ responses in stressed individuals.
Broadly, reduced NK CELL activity and depressed LYMPHOCYTE MITOGEN responses in stressed individuals.
116
\_\_\_\_\_ is the major etiology of acquired immunodeficiency in the world today
HIV
117
Immune alterations induced by measles include:
–T cell lymphopenia with depletion of T-dependent areas of lymph nodes and spleen
–Diminished in vitro T cell proliferation with mitogens or alloantigens
–Diminished antibody production
–These effects caused by direct infection of T cells and dendritic cells by measles virus, impairing antigen presenting/accessory function in T cell activation.
118
Much of the morbidity and mortality of measles is due to significant immune suppression which leads to _____ (Explain)
Superinfection;
## Footnote
–Most frequent complications: pneumonia, gastroenteritis, otitis media, gingivostomatitis, and other upper respiratory infections
–Superinfections often with common respiratory viruses, Staphylococcus aureus or Streptococcus pneumonia
119
Infectious of herpesvirus can cause transient depression of \_\_\_\_\_\_\_, especially with \_\_\_\_\_
cell-mediated immunity; CMV
120
Herpesvirus persistence has been implicated in the mechanisms of \_\_\_\_\_\_\_\_
immunosenescence
121
The immune suppression resulting from _______ infection is more pronounced than any other class of microbe (excluding HIV)
protozoan
122
Malaris results in decreased _____ immunity, leading to:
cell-mediated immunity;
## Footnote
–Increased susceptibility to infections by other microbes
–Delayed graft rejection
–Higher rate of various malignancies
123
Malaris likely plays a role in EBV-associated ______ in Africa (explain):
Burkitt's Lymphoma;
Malaria parasite inhibits the ability of cytotoxic T cells to maintain EBV transformed B cells under control, leading to lymphomas
124
\_\_\_\_\_\_ infections are not as well known to cause secondary immune suppression, with a notable exception being \_\_\_\_\_\_
Bacterial infections;
superantigens (staph and strep)
125
Superantigen activity leads to significant \_\_\_\_\_\_\_\_, but leads to an eventual decrease in _______ as well as ______ function
Superantigen activity leads to significant IMMUNE STIMULATION, but leads to an eventual decrease in T CELL NUMBER AND ACTIVITY as well as NEUTROPHIL function
