unit 4 autoimmunity Flashcards
autoimmunity
attacking own cells and tissues
loss of tolerance
B and T cells no longer tolerate self antigens
molecular mimicry
foreign protein resembles human protein
mechanisms that cause autoimmune diseases
impaired T regulatory cells, enhanced Th17 cells, viral infections, molecular mimicry, and genetic/development factors
symptoms of lupus
alternating flares and remissions
–> butterfly rash, hepatic inflammation, glomerulonephritis
principles of laboratory tests to diagnose lupus
ANAs –> testing serum for autoantibody (antinuclear) 90% positive
–> Anti-dsDNA and Anti-Smith are used to confirm lupus
homogenous stain pattern
associated with lupus
speckled stain pattern
associated with sjogren syndrome
nucleolar stain pattern
associated with scleroderma
nuclear membrane stain pattern
associated with primary billary cirrohsis
centromere stain pattern
associated with crest syndrome scleroderma
specificity of Anti-Sm
simplest and most specific test for lupus
signs and symptoms of rheumatoid arthritis
joint pain and swelling, progressive destruction of cartilage
rheumatoid factor
autoantibodies that acts against self antibodies
false positive and false negative results in laboratory testing for RF
present in other disorders like sjogrens syndrome which shows a false positive
diagnosis of rheumatoid arthritis
positive ANA screening test (homogenous or speckled)
–> Anti-CCP antibodies (60%-70%)
–> ESR inflammatory markers and CRP to monitor flare ups
mechanism of damage multiple sclerosis
- activated T cells surmount blood-brain barrier
- molecular mimicry of myelin basic protein
- inflammation surrounding CNS and causes demyelination
symptoms of multiple sclerosis
disturbance in visual acuity, motor disturbances, speaking
diagnosis of multiple sclerosis
clinical signs –> neurologic changes
increased IgG in CSF
antibody index testing to measure Anti-MBP antibody in serum and CSF
mechanism of myasthenia gravis
autoantibodies bind to acetylcholine receptor and blocks binding/causes degradation
symptoms of myasthenia gravis
muscle weakness, ocular disturbances
–> blepharoptosis (dropping eyelids
–> diplopia (double vision
oropharyngeal muscle weakness
diagnosis of myasthenia gravis
looking for antibodies against acetylcholie
–> anti-AchR antibodies
mechanism of diabetes mellitus
T cells lose tolerance to insulin producing beta cells which triggers cell mediated response
symptoms of type 1 diabetes
fatigue , joint aches, impaired visual activity, peripheral neuropathy (cannot feel pain anymore)
anti thyroid antibodies in thyroid diseases
laboratory tests used for autoimmune thyroid disease
Anti-thyroperoxidase and Anti-thyroglobulin, measure levels of T3 and T4
ankylosing spondylitis
cause: inflammation in sacroiliac joints
effect: destruction and fusion of joints
findings: HLA-B27 is risk factor
good pasture syndrome
cause: autoantibodies targeting collagen of glomerular basement membrane
effect: glomerulonephritis
sjogren syndrome
autoimmune disorder against lacrimal and salivary glands
effect: dry eyes/mouth and effects joints skin
scleroderma/CREST syndrome
cause: inflammation leads to activation of fibroblasts that produce excessive levels of collagen
effect: thickening and tightening of skin
pathogenesis of autoimmune hemolytic anemia
cold aagglutinin disease
significance of cold agglutinins
causes RBCS to clump together and be destroyed
cryoglobulins
antibodies that precipitate (clump together) at temperatures lower than body temperature
