RA - ONLINE MATERIAL Flashcards
1
Q
Associated gene polumorphisms
A
- Class II MHC: HLA-DR/P/Q/M -> 30% of genetic risk
- Class III MHCL TNF, C4, HS-70
- Hormone related genes: Prolactin, estrogen synthase, estrogen receptor, Corticoprotin RH
2
Q
Suite: non MHC related genes
A
- Lymphocyte associated: TCR, B cell, CTLA-4
- cytokine and cytokine receptors: TNF, CCR5, IL10, IL1, IL3
- othersL MBL, MMP3, NRAMP1
3
Q
Etiology: association with DRB1
A
- infectious agent in synovium
- arthritogenic antigen : cross reactivity with self
- continues presence of super antigen from EPV or MB TB
4
Q
Etiology: other possibilityes
A
- altered/aberrant T cell repertoire
- inability of Treg to control clonal expansion
- B cell etiology - antiarticular response
5
Q
Etiology: cyclic citrullinated peptides
A
- anti-cyclic citrullinated peptide antibodies
- citrullination is part of normal cell death but damage accelerates it. Its caused by deimidation of arginin via PADI enzyme which increases calcium
- PADI unfolds proteins for easy degradation
- includes cytoskeletal vimentin
- leakage of citrullinated peptides and PADI
6
Q
Acute changed in RA
A
- increased vascular flow: oedema, fibrin rice bodies
- endothelial activation: increased adhesion molecule expression, increased leukocyte adhesion, increased leukocyte transmigration
- vascular proliferation: high endothelial venules
- replication of Type B synoviocytes
- recruitment of type A synoviocytes
- fusion of both into giant cells
- involvement of immune response
7
Q
Chronic changes in RA
A
- recruitment of cells
- remodelling responses; large ratio of MMP/TIMP -> tissue degradation
- reduced apoptosis of synoviocytes
- proliferative response to hypoxia resulting from increase in HIF1a
- synoviocyte fusion
- formation of synovial pannus
- erosion of cartilage and bone
8
Q
Visible changes on Xray
A
- joint narrowing due to loss of cartilage
- erosions adjacent to cartilage
- jusxta articular osteopenia
9
Q
Chronic changes, suite
A
- increase pressure -> hypoxia in type B synoviocytes
- increase in HIF1a -> VEGF -> angiogenesis (poorly ordered)
- CXCL12
- ECM
10
Q
RA background
A
- most common chronic inflammatory joint disease
- 1% of pop
- F:M: 2-3:1
- onset increases with age
- peak onset 50-70
11
Q
Incidence of RA
A
- higher in NE, NA, and native american tribes
- incidenceL 40/100.000
- more common in lower education and low SES
12
Q
Etiology - environmental
A
- smoking is the strongest risk factor: follows a dose response. Associated with CCP and RF and with more severe disease
- alcohol lowers risk
- statins reduce risk of RA
- virus: EPV, Parvo B19 (not proven)
13
Q
Reproductive and endocrine etiology
A
- increase risk in women
- increse risk post-partum
- remission during pregnancy
- early menopause increase risk
- estrogen inhibits T supresor cells and enhances T-helper cell function
14
Q
Etiology - Genetic
A
- Genetic contribution 30%
- concordance monozygotic twins = 12-15%
- Concordance dizygotic twins = 3%
- HLADRB1 risk alleles: 0401, 0405
- havign 2 copies of allele increases risk
- influence development of seropositive RA
- associated with more severe disease
15
Q
What aspect of the huistory is most suggestive of an inflammatory arthritis such as RA?
A
- early morning stiffness
16
Q
RA Clinical features
A
- inflammatory history: morning stiffness for more than 30 min
- synovitis in 3+ joints
- symptoms last >6 weeks
- Viral illnesses can cause RA like symptoms
- other diseases have been excluded
17
Q
Onset of RA
A
- gradual onset 50%
- sudden onset 10-25%
- local soft tissue inflammation: carpal tunnel syndrome, bursitis
- systemic feature: fatigue, weight loss, fever, myalgia
18
Q
What are the joints most commonly affected by RA?
A
- MCP of hand
- proximal interphalangeal
- wrist
- elbow
- shoulders
- hips
- knees
- ankles
- MTP
19
Q
Typocal RA deformities
A
- ulnar dviation, subluxation at MCP
- swan neck deformity
- boutoniere
20
Q
Spine involvement
A
- Cervical spine
- Pannus at C1-C2
- Atlanto-axial subluxation
- sub-axial subluxation
- potential compression of spinal cord
21
Q
Morbidity and mortality in RA
A
- cardiovascular risk - main cause of mortality
- RA associated with 50-60% increased risk of CV mortality
- reduced with good control of inflammation
- Morbidity: CV disease, infection, lymphoma
22
Q
Extra-articular features of RA
A
- Systemic inflammatory condition - can affect other tissues
- Rheumatoid nodules commonest EA features
- presence of EA features is associated with worse prognosis
23
Q
Rheumatoid nodules
A
- occur in 30% of RA patients
- severe disease
- sero-positive disease (RF, antiCCP)
- occur typically on elbows but can occur anywhere
24
Q
Lung and heart disease
A
- pleural effusion, pleuritis
- fibrosis 5%
- rheumatoid nodules
- pericardial effusion, pericarditis
25
Q
Eye disease
A
- scleritis, episcleritis
- scleromalacia perforans: inflammation of the sclera with thinning and rupture of sclera
- Sicca syndrome: dry eyes,mouth
- Sjogren syndrome - 10% of patient
26
Q
Other EA manifestation
A
- Vasculitis
- Felty’s syndrome (splenomegaly +/- lymphadenopathy, neutropenia, leg ulcers, recurrent infection)
27
Q
Investigations
A
- Autoantibodies: RF, anti-CCP. Useful for diagnosis, prognosis, but not present in 100% of patients
- Non specific investigations: ESR, CRP -> markers of inflammation, useful for monitoring disease activity
