2: Autoimmune Inflammatory Arthritis Flashcards
what is rheumatoid arthritis
Inflammatory autoimmune disease characterised by joint pain, swelling and synovial destruction
in which gender is rheumatoid arthritis more common
Females (4:1)
what is the peak incidence for rheumatoid arthritis
50-75y
what causes rheumatoid arthritis
Combination of genetic and environmental factors. Genetic factors include HLADR1 and HLADR4. Environmental includes smoking + infection.
explain how rheumatoid arthritis presents
- Symmetrical polyarthritis
- Tends to affect smaller joints
- Morning stiffness >30m
- Swollen and painful joints (often without erythema)
which joints does RA typically affect
MCP and PIP
what is a never event in RA
That it affects DIPs
what are 5 signs of the rheumatoid hand
- Guttering
- Swan neck
- Boutoneire’s
- Z-shaped
- Positive squeeze test
what is guttering
Wasting of the interoessi muscles
what is swan neck deformity
- Hyperextension at PIPS
- Flexion at DIPS
what is boutonniere deformity
- Flexion at DIPs
- Hyperextension at PIPs
what is z-shaped deformity
Flexion at MCP, Hyperextension at DIPs
what is flexion at the PIPs and hyper-extension at the DIPs called
Boutonierre’s
what is hyperextension at the PIPS and flexion and the DIPS called
Swan neck
what is hypertension at the DIPS with flexion at the MCP joint called
Z-shaped deformity
What is a positive squeeze test
when there is pain on squeezing over MCP or Meta-tarsal joints
What is a deformity of the spine that can be present in rheumatoid arthritis
Atlanto-axial subluxation
What is a deformity of the feet that can be present in RA
Hammer toe
What are 4 constitutional symptoms of RA
- Malaise
- Low grade fever
- Myalgia
- Night sweats
What is a deformity of the skin present in RA
Rheumatoid nodules
what are 2 lung problems that may be present in RA
Fibrosis
Pleural effusion
what are 3 eye problems that can be present in RA
Episcleritis
Keratoconjunctivitis
Scleritis
what haematological disease is present in RA
Normocytic normochromic anaemia
how will RA of the cervical spine present
Atlanto-axial subluxation
What is felty syndrome
A severe form of seropositive RA. Presents with a triad of symptoms
What is the triad in felty syndrome
- Arthritis
- Neutropenia
- Splenomegaly
Explain the pathophysiology of RA
- autoimmune disorder triggered by interaction of genetic + enviroemntal
- citrullination (arginine to citrulline) occurs in type II collagen
- Susceptibility genes (HLA DR1 and HLA DR4) mean immune cells do not recognise the citrullinated protein and activate CD4 cells
- CD4 causes prolifération of B cells to produce antibodies which enter joints
- CD4 cells also recruit macrophages (using IL17 and IFNg) which then release TNFa, IL1 and IL6 which cause synovial cells to proliferate forming a pannus
What 4 investigations are ordered in RA
- CRP and ESR
- anti-CCP
- RF
- X-ray
How will CRP and ESR present
Raised
What antibody is very specific for RA
anti-CCP
What is rheumatoid factor
IgM antibody
What is the problem with rheumatoid factor
low specificity
What criteria is used to diagnose rheumatoid arthritis
American College of Rheumatology Criteria
What score on the american college of rheumatology criteria defines RA
> 6/10
What are the 4 categories in the american college of rheumatology criteria
- Joint involvement
- Antibodies (RF, ACPA)
- Serology (CRP, ESR)
- Duration of symptoms (> or < 6W)
if individuals have suspected RA, what x-rays should be ordered
X-ray of the hands and feet
What is a mnemonic to remember the 3 early signs of RA on x-ray
JLS
What ate the late findings of RA on x-ray
Juxta-articular osteopenia
Loss of joint space
Soft-tissue swelling
What score is used to look at the activity of RA for a patient
DAS28
What are the 4 domains of the DAS28 score
- No. swollen joints
- No. tender joints
- ESR + CRP
- Subjective (line 1-10cm)
What score indicates active disease in DAS28
> 5.1
What score indicates low disease activity in DAS28
<3.2
What score indicates remission in DAS28
<2.6
What is first-line management for RA
disease modifying anti-rheumatic drugs (DMARD)
What are the 4 dMARDs that could be offered
- Methotrexate
- Sulfalazine
- Hydroxycholorquine
- Lefluonomide
what is the most common dMARD offered
Methotrexate
What monitoring is required for methotrexate
FBC + LFT
Why is FBC and LFTs monitored for methotrexate
Due to risk of myelosupression and liver cirrhosis
Which is the only dMARD considered safe for pregnancy
Sulfasalazine, hydroxychloroquine
What is second-line treatment for RA
Biological agents
What are the criteria for sarliumab
DAS28 >5.1
What is the mechanism of action of Sarliumab
monoclonal antibody raised against IL6
What are 4 alternatives to sarliumab
etanercepts, infiximab, adalimumab
What is third-line medication for RA
rituximab
What is the MOA of ritxuimab
anti CD20 and therefore depletes B cells
What is the criteria for rituximab
- DAS28 >5.1
- Tried methotrexate and at least on other anti-TNF
What are 5 factors associated with poor prognosis of RA
Female Onset >60 Smoker Prolonged progression Raised CRP, ESR, RF, ACPA
What are 5 complications of RA
- Joint deformity
- Lung fibrosis
- Myocarditis
- Pericarditis
- Amyloidosis
- Septic arthritis
- Sjogren’s syndrome
What is psoriatic arthritis
Seronegative spondyloarthropathy that occurs with psoriasis
What gene is present in 50% of cases of psoriatic arthritis
HLAB27
what % of individuals with cutaneous arthritis will develop joint arthritis
10-20%
What are the 5 patterns of psoriatic arthritis
- Asymmetrical oligoarthritis
- Arthritis mutilants
- Psoriasis spondyloarthropathy
- DIP predominant
- Symmetrical, RF negative arthritis
What is the main presentation of psoriatic arthritis
Asymmetrical oligoarthritis (MCP, DIP, PIP) (70%)
How does psoriatic arthritis differ from RA
It is asymmetrical oligoarthritis, whereas RA is typically symmetrical
What is arthritis mutilans
Severe form of psoriatic arthritis that presents with telescoping of the fingers
What joint does psoriatic spondyloarthropathy affect
Spine (40%)
OE/ what may be seen in psoriatic arthritis
Erythematous, silver scaly patches over extensor surfaces (hands + knees)
Do joint symptoms or cutaneous symptoms come first in majority of individuals
Cutaneous - often precede joint symptoms by several years in 75%
What surface is the rash in psoriasis over
Extensor
How may fingers present in psoriatic arthritis
Dactylitis
How may nails present in psoriatic arthritis
- Onychodystrophy (Pitting)
- Onycholysis
How may eyes present in psoriatic arthritis
Chronic uveitis
How may joints present in psoriatic arthritis
Tenosynovitis
What criteria is used for psoriatic arthritis
CASPAR
What 6 items is the CASPAR criteria based on
- Evidence psoriasis (FHx, cutaneous)
- Nail dystrophy
- Negative RF
- Dactylitis
- Radiologyical
What 3 findings may be seen on x-ray of the hands in psoriatic arthritis
- Fluffy periostitis
- Pencil in cup deformity
- Acroosteolysis
What is pencil in cup deformity
Re-absorption of head of middle phalanx and widening of base of distal phalanx
What is acrostolysis
Reabsorption of distal phalanx
How may the spine present
Syndesmophytes
Paravertebral ossification
How is mild psoriatic arthritis managed
NSAIDs, PPI
How is moderate psoriatic arthritis managed
dMARDs
What investigation should be performed prior to starting someone on anti-TNF for RA and why
chest x-ray, to check for TB. As anti-biologics may cause re-activation
