Autoimmune diseases Flashcards
Libman-Sacks endocarditis
Sterile platelet vegetations occuring on mitral valve, leading to valve thickening + regurgitation sx; vegetations can be on either surface of valve (mainly undersurface)
Renal involvement in scleroderma and which type it’s more often associated w/
Scleroderma renal crisis (SRC)- characterized by sudden onset of malignant HTN, which causes acute renal failure
- Occurs mostly in diffuse scleroderma
Pattern of Raynauds
Pallor (white) –> cyanosis (blue) –> hyperemia (red)
Manometry of scleroderma and why
All the waves are flattened- smooth muscle of esophagus is replaced by collagen, resulting in decreased peristalsis
Presentation of antiphospholipid syndrome
Hypercoagulable state results in arterial and venous thrombosis (DVT, hepatic vein, placental, cerebral strokes)
Important player in scleroderma
In response to inciting endothelail injury, CD4+ T cells respond by releasing cytokines and other inflammatory cells/ fibroblasts, which results in widespread small blood vessel damage –> progressive fibrosis –> intimal thickening –> occlusion of organ supply –> fibrosis of organ/ skin
What is used to detect early scleroderma?
Distorted nailfold capillary loops - indicates vascular damage that’s happening all over the body
Types of lung involvement in scleroderma and which one is associated w/ which type (limited vs. diffuse)
1) Interstitial fibrosis- seen in diffuse scleroderma
2) Pulmonary arterial HTN- seen in limited scleroderma
Etiology of Sjogren
Primary- sicca syndrome
Secondary- associated w/ other autoimmune disorders (esp. RA)
Lupus anticoagulant’s effects on bleeding tmie
In vitro, causes elevated PTT; however, in vivo, produces hypercoagulable state
Difference in epidemiology between SLE and drug-induced lupus (2)
In drug induced lupus, older individuals are affected (e.g. 50-70), and there is no gender preference
Autoantibodies found in SLE and how they can be used for diagnosis
1) ANA: sensitive but not specific for lupus
2) Anti-dsDNA: specific for lupus; titers fluctuate w/ disease activty so levels can be used to manage pts; however, this level can be low when disease is quiescent
3) Anti-Sm: antibody against nuclear non-histone proteins; specific for lupus; titers are elevated regardless of disease activity
*Presence of Anti-dsDNA + Anti-Sm is virtually diagnostic for SLE
Epidemiology of Sjogren syndrome
Affects 40-60 year olds
Lab complement levels in SLE
Decreased C4, C5, CH50 due to immune complex deposition + activation of complement
Autoantibodies associated w/ scleroderma
1) ANA- sensitive but not specific
2) Anti-centromere antibodies- limited SSc
3) Anti-DNA topoisomerase I antibodies (Anti-Scl70) - diffuse SSc
4) Anti-RNA polyermase III antibody- diffuse SSc; increased risk for SR
Presentation of drug-induced lupus
Similar to SLE but CNS and renal sx are rare
Autoantibody asscociated w/ diffuse scleroderma
Autoantibody against DNA topoisomerase I (Anti-Scl70)
Autoantibodies found in drug-induced lupus
ANA, Anti-histone antibodies
Anti-ds DNA is rare
Autoantibodies associated w/ scleroderma renal crisis (SRC)
Autoantibodies to RNA polymerase III
Mechanisms of injury in SLE
1) Type III HSR- immune complex deposition in variety of tissues
2) Type II HSR- autoantibodies specific for RBC, WBC, platelets opsonize these cells
3) Antiphopsholipid autoantibodies- hypercoagulable state
Autoantibodies present in Sjogren
1) ANA - sensitive but not specific
2) Anti-ribonucleoprotein antibodies (Anti-SSA/Ro, Anti-SSB/La)
3) RF- can be present w/o RA
Histology of SRC
Onion skinning appearance of arterioles (malignant HTN)
Unexplained spontaneous abortions, premature birth, pre-eclampsia
Antiphospholipid syndrome- due to placental thromboses
Types of antiphospholipid antibodies (3)
1) Anticardiolipin
2) Anti-beta2 glycoprotien 1
3) Lupus anticoagulant
