pg 120-158 Flashcards
What percentage of the population is affected by autoimmune disease?
2-5%
Failed self-tolerance is referring to what?
Having self-reactive T and B cells- or an immune response to ones one’s own tissue antigens
What is immunologic tolerance?
The unresponsiveness to an antigen that is induced by exposure of specific lymphocytes to that antigen
What is Central Tolerance?
The principal mechanism is the antigen-induced death of self-reactive T and B lymphocytes during their maturation in the central (the places they are generated) lymphoid organs
Where are T cells and B cells generated?
T cells in the Thymus and B cells are generated in the bone Marrow (T=T and B=B)
What does peripheral tolerance refer to?
It refers to the death/deletion or inactivation of self-reactive T and B cells at the peripheries that escape the Thymus and could otherwise wreak havoc in the body
What does the breakdown of self-tolerance and development of autoimmunity result from?
A combination of inherited genes which influence lymphocyte tolerance, and environmental factors, such as infections or tissue injury, that alter the display of self-antigens
What are the prime targets for autoimmune disorders?
Connective tissue and vessels
Several autoimmune diseases are linked with what?
The Human Leukocyte Antigens (HLA) locus of genes are chromosome 6
What is the HLA responsible for?
It regulates the immune system by encoding for antigen-presenting proteins (presents allergen to T-cell, T-cell decides whether or not to kill it)
Is there a greater incidence of the same disease between dizygotic or monozygotic twins?
Monozygotic
The group of people most likely to develop autoimmune disorders are ___ and why?
Women of reproductive age due to high estrogen levels?
The display of tissue antigens may be altered by what 2 things?
Environmental factors and infections
Anergy refers to what?
Self antigens in peripheral tissues becoming functionally inactive
Lupus affects primarily which organs?
Skin, kidneys, serosal membranes, joints, heart, plus CNS
A disease which is described with an insidious inset, unpredictable, and relapsing could be…?
Lupus
Immunologically, Lupus is associated with an enormous array of autoantibodies, including ___
ANA (antinuclear antibodies) as well as IgG
Lupus is most common in…?
Women of childbearing age- more specifically African American woman of child-bearing age
What are some of the most common signs of Lupus? (There are lots)
Fever of unknown origin, photosensitivity (which leads to Malar rash, discoid rash, dermoepidermal degeneration), serositis (pleuritis or pericarditis), hair loss, GI discomfort, Libman-Sacks endocarditis (‘warts’ on Bicuspid valve)… painless oral ulcers, non-erosive arthritis, CNS problems, fatigue, myalgia, pulmonary and liver fibrosis, pancytopenia, splenomegaly
The fundamental defect in SLE is…?
The failure to maintain self-tolerance, leading to the production of large number of autoantibodies that can damage other tissues directly or via immune-complex deposits
The best way to diagnose SLE is to look at ___ which means what? And how specific is the test?
ANA’s, which means that 99% of Lupus patients will show positive for ANA’s. It is 80% specific, meaning that other diseases can show positive for ANA, but 80% of those positive results will be from Lupus
The ANA test uses ___
Immunofluorescence
Most organ damage in SLE is caused by what?
Immune complex deposition
The most common cause of death to Lupus patients is…? Another common cause of death is…? What are they also at risk of?
Renal failure… Coronary artery disease is another cause, which can lead to MI and infection. They are also at an increased risk of B cell lymphoma
What is the survival rate of SLE after diagnosis?
95% 5-year survival
How many Americans have Lupus?
1.5 million
A condition that is secondary to other autoimmune disorders, is most common females aged 35-45, can be triggered by a virus, and is associated with dry eyes and dry mouth would be…?
Sjogren syndrome
Dry eyes and dry mouth when isolated can be called…?
sicca syndrome
Sjogren syndrome patients are also at increased risk of…?
B cell lymphoma
Sjogren syndrome is an autoimmune disease caused by…?
CD4+ T cell reactions against unknown antigens in the ductal epithelial cells of the exocrine glands
Sites of damage from most common to least common in Sjogren syndrome are:
Lacrimal (keratoconjunctivitis sicca and salivary (xerostomia) glands, and less commonly the vagina, nasopharynx (laryngitis), upper airways (bronchitis), kidneys, CNS, muscles
What percentage of Sjogren syndrome patients will test positive for ANA?
90%? (I have noted)
Explain Rheumatoid Arthritis
It is a systemic, chronic inflammatory disease affecting many tissues but mainly the joints to produce nonsuppurative proliferative synovitis that often destroys the articular cartilage and bone underneath
Systemic sclerosis is defined as…?
An immunologic disorder characterized by excessive fibrosis in multiple tissues, obliterative vascular disease, and evidence of autoimmunity, mainly the production of multiple autoantibodies