-
When do autoimmune diseases occur?
Individual produces antibodie or T cell response to his/her own antigens
-
What theory states that Burnet postulated that when an error in self-recognition occurs during fetal life and lymphs against an autoantigen are not destoryed, then autoantibodies are produced?
Forbidden clone theory
-
What theory states that clones developed during fetal life are not stimulated by low doses of antigens and the ability to produce antibodies against higher doses of antigens is still present?
Clonal anergy
-
What theory states that some antigens are hidden from the immune system during fetal development, and when tissue is damaged, the hidden cells are exposed?
Sequestered antigen theory
-
What theory states that supporessor T cells control antibody production by B cells and if suppressor T cells exhibit decreased activity, then antibodies against autoantigens are produced?
Immunologic deficiency theory
-
What theory states that an individual can make antibodies or reactive T cells to an infectious agent that cross reacts with self antigens?
Molecular mimicry
-
What theory states that a number of bacteria and viruses are known to nonspecifically stimulate B cells, and if these B cells have activity against self antigens, an autoimmune disease can result?
Polyclonal B cell activation
-
What clinical conditions are antinuclear antibodies (ANAs) associated with?
- Systemic lupus erythematosis (SLE)
- Mixed connective tissue disease (MCTD)
- Rheumatoid arthritis (RA)
-
What is an anti-antibody, typically IgM, that bind to the Fc portion of abnormal IgG?
- Rheumatoid Factor (RF)
- Chronic hepatitis
- SLE
- Syphilis
-
What clinical conditions are associated with cryoglobulins?
- Autoimmune diseases like:
- Vasculitis
- Glomerulonephritis
- SLE
- RA
- Sjogren syndrome
-
What clinical condition is a chronic, noninfectious inflammatory disease involving many organs and tissue injury is caused by autoantibodies and immune complexes deposited into the tissues?
Systemic lupus erythematosus (SLE)
-
What clinical condition is a chronic, noninfectious, systemic inflammatory disease that primarily afects the joints and is due to production of IgG or IgM antibodies against IgG in the synovium?
Rheumatoid arthritis
-
What clinical condition is consisten with the findings:
ESR increased
CRP increased
RF positive
Cryoglobulins positive
ANA positive or negative
Synovial fluid is cloudy with WBC between 5000-20000, increased protein
Poor mucin clot development
Complement decreased
RF positive
Rheumatoid arthritis
-
What clinical condition is an inflammation of the salivary and lacrimal glands causing dryness of the mouth and eyes?
Sjogren syndrome
-
What clinical condition is consistent with the findings:
Polycolonal hypergammaglobulinemia
Autoantibodies agains the salivary glands
RF positive
ANA speckled or diffuse pattern
Anti-SSA
Anti-SSB
Sjogren syndrome
-
What clinical condition has:
an increased rate of RBC destruction
DAT positive
Cold agglutinins (sometimes)
Autoantibody against RBC antigens
Autoimmune hemolytic anemia
-
What disease occurs when
Humoral and cellular immunity are activated
Destruction of normal thyroid tissue leads to hypothyroidism
Loss of thyroid function
Low levels of thyroid hormones in the blood
Detection of antithyroid antibodies
Hashimoto disease
-
What disease is characterized by:
Hypoplasia and diffuse goiter caused by an autoantibody reacting with thyroid receptor on cells that overstimulates the thyroid gland
Autoantibody mimics the activity of thyroid stimulating hormone (TSH)
TT3 increased
FT3 increased
TT4 increased
FT4 increased
TSH decreased
Exophthalmos
Infiltrative dermopathy
Thyrotoxicosis
Graves disease
-
What disease is a:
Neuromuscular disease in which the nerve muscles do not function normally
Most patients exhibit antibodies to acetylcholine receptors
Myasthenia gravis
-
What disease is:
Considered a chronic progressive inflammatory disease with demyelination of the nerves
Active lesions (plaques) contain CTLs, T helper cells, and macrophages
IgG increased in CSF
Oligoclonal bands in CSF
Multiple sclerosis (MS)
-
What differentiates true increase of IgG due to a production rather than increases in permeability of the blood-brain barrier?
IgG index
-
What is the IgG index calculation?
-
What is the reference range for IgG index?
0-0.77
-
What disease has:
Islet cell destruction in the pancreas
Autoantibodies and CTLs reactive against pancreatic beta cells produce marked atrophy and fibrosis of the islet cells - causing insulin deficiency
Type 1 diabetes
-
What types of responses are humoral mediated and immediate?
Types I-III
-
What type of responses are cell mediated at delayed?
Type IV
-
What type of hypersensitivity reaction is:
Classified as an immediate hypersensitivity reaction b/c it occurs within minutes after reexposure
After 1st exposure, basophils and mast cells are sensitized with IgE
After 2nd exposure, IgE binds to a specific allergen and chemical mediators are released
Type I hypersensitivity (anaphylactic)
-
What do allergens contacting the bronchus cause?
Asthma
-
What is the systemic form of type I hypersensitivity?
Anaphylaxis
-
What mediator of Type I hypersensitivity:
Causes contraction of bronchioles and smooth muscle of blood vessels
Increases capillary permeability
Increases mucus secretion in the airway
Histamine
-
What mediator of Type I hypersensitivity:
Causes vasodialationÂ
Increased vascular permeability
Prostaglandins
-
What mediator of Type I hypersensitivity:
Causes erythema and wheat formation
Has 30-100 times the ability of histamine to cause bronchospasms
Stimulate mucus secretion in the airways
Leukotrienes
-
What type of hypersensitivity reaction is
Due to IgG or IgM antibodies directed against cell surface antigens
PMNs bind to antibody sensitized cells and destroy the cells by phagocytosis or antibody dependent cellular cytotoxicity reaction
Type II hypersensitivity
-
What occurs when antibody-antigen complex on cell surface activates the complement pathway to cause cell lysis?
Complement mediated cell lysis
-
Name an example of Type II hypersensitivity reactions
Incompatible blood transfusions
-
What type of hypersensitivity reaction is:
When immune complexes are deposited on tissues, causing inflammation
Can activate complement, which can lyse nearby (innocent bystander) cells
Can stimulate degranulation of granulocytes, which triggers inflammation and tissue damage
Type III hypersensitivity (immunecomplex)
-
What 2 sites are where immune complexes are often deposited?
- Heart valves
- Renal glomeruli
-
What happens when immune complexes are deposted into the renal glomeruli?
- Causes inflammation of the kidney - glomerulonephritis
- Possibly renal failure
-
What hypersensitivity reaction is:
Caused by soluble factors or lymphokines released by T cells
Antibody and complement are NOT involved in this reaction
Recruitment and activation of the cells takes 24-72 hours, and therefore referred to as delayed hypersensitivity
Type IV hypersensitivity (cell mediated)
-
How does Type IV hypersensitivity (cell mediated) reaction work?
- Lymphokines are produced by T cells
- These chemicals attract macrophages that become activated, cause them to degranulate
- As more macrophages arrive at the site, ulceration and necrosis occurs
-
Name examples of Type IV hypersensitivity (cell mediated)
- Tuberculin-type hypersensitivity - swelling at the site of subcutaneous injection
- Contact sensitivity (dermatitis) - allergens from poison ivy or poison oak
-
What clinical condition is:
Marked deficiency of all classes of immunoglobulins is detected after about 6 months of age
Recurrent, life-threatening infections occur with encapsulated bacteria (Strep pneumo and H. influenzae)
B cells are markedly decreased or absent
Bruton X-linked agammaglobulinemia
-
What clinical condition is:
X linked genetic disease
Serum IgM increased
IgG and IgA are markedly decreased or absent
Defect in CD40 ligand on T helper cells prevents class switching from IgM to IgG, IgA, or IgE
Patients prone to respiratory tract infections
Autoantibodies to platelets, RBCs, and neutrophils
Hyper-IgM syndrome
-
What clinical condition has:
Patients present with small amounts or absence of serum and secretory IgA
Usually caused by a genetic defect or by drugs (phenytoin and penicillin)
Anaphylaxis may result if IgA is administered to someone with this deficiency (blood transfusion)
Selective IgA defiency
-
What clinical condition is:
Autosomal recessive disorder that presents with ataxia, telanectasia, recurrent sinopulmonary infections, high incidence of malignancy, and variable immune defects
IgA deficiency
Sometimes IgE deficiency
NOT primarily an immunodeficiency but a defect in a kinase gene that regulates the cell cycle
B and T helper cells are affected
Ataxia-telangiectasia
-
What clinical condition has:
Symptoms that include hypocalcemic tetany, due to underdevelopment of the thymus, and heart disease
Immune defect is variable, from slight decrease in T cells to no T cells in bloodstream
Patients very susceptible to opportunistic infections and have poor prognosis
Congenital thymic hypoplasia (DiGeorge syndrome)
-
What clinical condition has:
Accumulation of nucleotide metabolites in all cells, which is particularly toxic to T and B cells
T cells decreased
Children often have an underdeveloped thymus, lack of tonsils or lymph nodes, hypogammaglobulinemia, and lymphopenia
Defects in adenosine deaminase (ADA) or purine nucleotide phosphorylase (PNP)
-
What clinical condition is:
With an MHC class II deficiency, T helper cells fails to develop - patient present with hypogammaglobuminemia and no CMI response
MHC class I defiency is less severe - loss of CTLs and response to intracellular pathogens
Bare lymphocyte syndrome
-
What clinical condition has:
A mutation in the gene that codes for the Wiskott-Adrich syndrome protein (WASP) - a protein involved with cytoskeletal reorganization necessary for delivering cytokines
Defect prevents T helper cells from delivering lymphokines to B cells, macrophages, and other target cells
Patients demonstrate eczema, throbocytopenic purpura, and increase risk of infection
Platelets are small and defective
Wiskott-Aldrich syndrome
|
|