Mar29 M1-Introduction to Autoimmune Diseases Flashcards
most general symptoms that may be signs of auto-immunity
constitutional: fever, weight loss, poor appetite
non-specific: Raynaud’s (fingers white then blue then red), Sicca (dry eyes, dry mouth + CT disease), diffuse lymphadenopathy
symptoms that are highly associated with autoimmune disease (to check before doing lab tests)
- arthritis
- skin rash
- mucosal involvement
- lung involvement
- ocular symptoms
- renal dysfunction
- peripheral nerve defect
big thing we want to determine in inflam disease dx
- if disease is inflammatory or not
- ostearthritis = non inflam, arthritis = inflam
problem of lab tests in autoimmune diseases
are not diagnostic because the diseases in rheumatology are rare. more likely that someone doesn’t have disease
non specific tests done in autoimmune disease
- CBC
- creatinine
- liver function
- UA
- urine protein measurement (kidney involvement is common in autoimmune)
lab tests for inflammation and for immune activation
for inflammation: ESR (erythrocyte sedimentation rate) and CRP
for immune activation: C3 and C4
auto-antibodies in autoimmune diseases
-only ASSOCIATED with these diseases but may not play role in pathophgy
-false - and false + are possible
-level doesn’t reflect how sick pt is
-
auto-Ab often found in lupus
anti-nuclear Ab (ANA) (only association. doesn’t cause lupus)
last dx step in autoimmune diseases
biopsy of an affected organ like the kidneys after noticed proteinuria for example
different kinds of autoimmune diseases
- Connective tissue diseases (SLE, slceroderma limited or diffuse, Sjogren’s syndrome, Mixed CT disease (MCTD))
- Inflammatory myositis
- systemic vasculitis
- inflammatory arthropathies (arthritic psoriasis, etc.)
scleroderma charact
- severe fibrosis (sclerosis = fibrosis) of skin, blood vessels, lung, GIT, kidneys and other organs. hard to move
- affects skin in limited (CREST syndrome) or diffuse pattern
2 things often found in pts with scleroderma
- Raynaud’s sign
- positive ANA
Sjogren’s syndrome charact
- affects exocrine glands
- xerostomia, xerophtalmia (dry mouth and eyes), joints, lungs, kidneys, CNS, etc.
2 things often found in Sjogren’s disease patients
anti-Ro (SSa) and anti-La (SSb) auto-Abs
MCTD (mixed CT disease) definition
- defined as having positive anti-RNP (rhybonuclear protein) Ab
- autoimmune disease where manifestations are normally seen in 3 other autoimmune diseases can be seen
- SLE
- scleroderma
- inflamatory myositis
things often seen in MCTD
- Raynaud’s sign
- lung involvement
- anti-RNP antibody
SLE charact
- affects mostly young women
- characterized by immune complex deposition in affected organs
how mortality in lupus compares to mortality in healthy individual
2-5x greater mortality rate in lupus
how lupus is diagnosed
- there’s a table with 11 criteria but is mostly used to check who to enter in a clinical trial
- real dx is with expert opinion (might dx lupus if lacking signs. might say it’s not lupus even if have a lot of signs)
11 manifestations of lupus
- malar rash 2. discoid rash 3. photosensitivity 4. oral ulcers 5. arthritis 6. serositis 7. renal disorder 8. neurologic disorder 9. hematologic disorder 10. immunologic disorder 11. ANA
specific clinical manifestations you really look for in SLE
- cutaneous manifestations
- mucosal ulcers
- arthritis
- lupus nephritis
- serositis
- hemato prob
- auto Ab
3 categories of skin rashes in lupus
acute LE = localized (malar) or generalized
subacute LE = annular or papulosquamous
chronic LE = classical DLE (localized, generalized), hypertrophic DLE, lupus panniculitis, lupus tumidus, DLE (lichen planus overlap)
most common rash in lupus
malar rash
- butterfly rash below eyes, on the cheeks
- DOESN’T affect the nasolabial fold
- photosensitive (CAUSED BY UV LIGHT)
- non scaring bc affects superficial skin
discoid rash charact
- involvement of deeper skin (dermis) = alopecia, depigmentation, scarring
- less photosensitivity than malar rash
major cause of lupus morbidity and mortality on the long-term
lupus nephritis (in 60% of lupus patients)
- need to monitor SLE pts regularly for kidney fct and UA + protein qt (major reason why lupus mortality decreased)
- need bx to dx lupus nephritis
serositis meaning (one of the 11 criteria in lupus)
- pleuritis, pericarditis and peritonitis
- shortness of breath, pleuritic pain (distinct from MI bc varies with deep breath)
- can have tamponade (one cause of lupus mortality)
hematologic involvement in lupus: things that can be seen
- chronic anemia (hemolytic for ex)
- ITP, TTP
- cytopenias
main Ab in lupus
ANA (anti-nuclear Ab)
how false positives with ANA testing are avoided
serum volume that is collected is diluted in a lot of saline. greater dilution = reduces false + (you get more specificity)
