Pathology- Autoimmune Diseases Flashcards
What are autoimmune disorders?
When the immune response is against self-antigens, and the body cannot differentiate “self” from “non-self”
What is systemic lupus erythematosus (SLE)?
multisystem inflammatory disease which involves the skin, joints, kidney and other organs.
What are the most important diagnostic antibodies (Ab)?
those against nuclear proteins (ANA). 2x (double stranded). Sm (anti Smith). Antihistone Ab.
What is the pattern of nuclear staining on a + ANA test for SLE?
homogenous or diffuse nuclear staining
What is a special pattern of staining that is more characteristic of SLE on a ANA test?
Rim pattern
What is the etiology of SLE?
unknown
What is most of the damage caused by in SLE?
vasculitis
Where in the body does SLE occur?
All over- immune complexes deposit in all tissues
What is the prevelence of SLE?
mainly women (9:1), especially in childbearing age, 2-3x high in blacks and hispanics.
What is the skin presentation in SLE?
erythematous rash in sun, “butterfly” rash on face is most characteristic.
What happens in the joints of 90% of SLE patients?
polyarthralgia
What is polyalthralgia?
inflammatory synovitis without joint destruction, often with pain (1st sign of SLE)
What happens in the kidneys of 75% of SLE patients?
glomerularnephritis
What Ab is mainly involved with glomerularnephritis in SLE?
IgG
What is the mesangial lupus glomerularnephritis?
Mildest form, where immune complexes and complement are found in the mesangium. prognosis is excellent
What is diffuse proliferative lupus nephritis?
most serious form of renal disease in SLE. epithelial crescents present. many pt’s progress to renal failure.
What might occur in the respiratory system of SLE pts?
Diffuculty breathing, wheezing and chest pain during physical activity might occur
What might occur in the CNS of SLE pts?
vasculitis might lead to hemmorage, memory loss, anxiwty and depression are neurological Sx of lupus
What might occur in the heart of SLE pts?
pericarditis is the most common finding, Libman-Sacks endocarditis with sterile vegitations.
How can you differentiate drug-induced lupus from SLE?
no sex predominance, no CNS or renal involvement, Ab to histones
What is chronic discord lupus (DLE)?
affects the skin but only in sub exposed patients, no organ system involvement
What types of rash form on the skin of DLE pt’s?
circular rashes and papular/anular rings on trunk
How can you differentiate DLE from SLE from lesions on the skin?
in DLE the areas without the rash will not have the + ANA test because DLE is not systemic
What are some clinical features of Sjoren syntrome (SS)?
keratoconjunctivitis (dry eyes), xerostomia (dry mouf), possible parotid enlargement
What population does SS affect?
women aged 30-65 (2nd most common connective tissue diesease after SLE)
SS patients have a 40% increase risk of developing what type of tumors?
lympomas (esp on the skin)
There is a widespread deposition of what molecules in Progressive Systemic Sclerosis (PSS)?
collagen
What tissues are affected in PSS?
skin and organs (esp the kidney)
What are some Ab’s specific for PSS?
nucleolar Ab to RNA polymerase, Ab to Scl-70
What is the staining pattern of PSS?
nucleolar pattern
What is the clinical presentation of PSS?
arteries, arterioles and capillaries are destroyed
What happens in the kidneys of PSS?
fibrinoid necrosis in afferent arterioles
What occurs in generalized PSS?
severe and progressive disease of the skin and organs
What the the progression of PSS?
early Sx of Raynauds, followed by edema in fingers and hands including a “stone face,” and then organ involvement
What are the color changes in Raynauds?
White –> Blue –> Red
Why does the “stone face” occur in generalized PSS?
there is atrophy of the muscles in the temple, face and neck. these changes are called Mauskopf (mousehead).
What occurs in diffuse cutaneous CREST?
Calcinosis, Raynauds, Esophageal dysmotility, Sclerodactyly, Telangiectasia
What is the most common form of myopathies?
juvenile dermatomysitis
What is the prevelence of myopathies?
3:1 prevelence in blacks vs whites, 2:1 female, may overlap other diseases like SLE, PSS, and SS.
What is the clinical features of polymyositis?
chronic inflammatory muscle disease, affects adults 40-50’s, no cutaneous involvement
What are the clinical features of dermatomyositis?
inflammatory involvment of the skin and muscles, difficulty standing or walking, liliac rash of eyelid, grotten lesions over knucles
What % of dermatomyositis pt’s develip cancer?
20-25%
What types of diseases comprise the “Mixed connective tissue disease”?
SLE, PSS, polymyositis/dermatomyositis
Where is the Ab directed in Mixed connective tissue disease?
A ribonucleoprotein particle containing U1 ribonucleoprotein (including Jo-1 and PM-1)
Where is the Ab NOT directed in Mixed connective tissue disease?
dsDNA
What is the staining pattern in Mixed connective tissue disease?
Speckles pattern (they bind to the riubonucleoproteins)
