MSK Flashcards
2 major divisions of arthritis
OA (degenerative)
inflammation
3 main causes of joint inflammation
- infection
- crystal arthritis
- immune mediated (autoimmune)
which one is primary joint inflammation
autoimmune
which one is secondary joint inflammation
infection and crystal arthritis
examples of infection in joint inflammation (2)
septic arthritis
TB
examples of crystals arthritis in joint inflammation (2)
gout
pseudogout
which are sterile joint inflammation
crystal arthritis
autommune
which are non sterile joint inflammation
septic arthritis
TB
speed of onset of OA
slow
speed of onset of immune mediated arthritis
acute
speed of onset of crystal arthritis and septic arthritis
rapid
which arthritis has both CRP & WCC elevated
septic arthritis
what is the key investigation of septic arthritis
joint aspiration and send fluid for gram stain and culture
management of septic arthritis
lavage (joint washout) and IV antibiotics
what are the 3 kinds of autoimmune arthritis
- lupus
- seronegative arthritis
- rheumatoid arthritis
where is the primary site of pathology of RA
synovium
where can synovium be found
synovial joints
tenosynovium surrounding tendons
bursa
sex bias of RA
F:M = 2:1
features of RA (4)
polyarthritis
chronic
pain, swelling, morning stiffness
joint erosions
what are detected in blood in RA
autoantibodies
what is the strongest genetic risk factor in RA
HLA-DR
what are in HLA class 1
HLA class A, B , C
what are in HLA class 2
HLA class D
where are HLA class 1 expressed on
all cells
what are associated with HLA class 1
CD8 killer cells
where are HLA class 2 expressed on
only on APCs eg dendritic cells, macrophages, B cells
what are associated with HLA class 2
CD4 helper cells with B cells
HLA class 1 associate with which disease in RA
ankylosing spondylitis
which HLA associate with ankylosing spondylitis
HLA-B27
why autoantibodies in RA but no ankylosing spondylitis
HLA class 2 implicates CD4 T cells and B cells
RA pattern of joint involvement (symmetry or not, how many joints, large or small joint)
symmetrical
polyarthritis
always small joints invovled
where do RA most commonly affect
hand and feet
common affected joints by RA
MCPJ
PIPJ
wrists
knees
ankles
MTPJ
which arthritis associate with morning stiffness
RA
which arthritis associate with worse with activities
OA
which joints are affected by OA
DIPJ
PIPJ
thumb CMCJ
MCPJ
what are some systemic symptoms of RA
fatigue
fever
weight loss
what are some organ-specific extra-articular features of RA
subcutaneous nodules
lung diseases (ILD, fibrosis, pleuritis)
vasculitis
neuropathies
amyloidosis
ocular inflammation (eye episcleritis)
felty’s syndrome
where are subcutaneous nodules found in RA
central area of fibrinoid necrosis surrounded by histiocytes and peripheral layer of connective tissues
what can be found in RA in blood
rheumatoid factors (Ab that bind to IgG)
anti CCP antibodies
what is pannus in RA
synovium becomes proliferated mass of tissue due to neovascularisation, lymphangiogenesis, inflammatory cells
what cells does healthy synovial membrane has
macrophage like (type A synoviocyte)
fibroblast like (type B synoviocyte)
type 1 collagen
what are different types of RA pathogenesis (cellular and molecular pathways)
autoreactive B cells
autoreactive T cells
cytokines (TNF alpha, IL-6, IL-1)
treatment for autoreactive B cells RA
rituximab
treatment for autoreactive T cells RA
abatacept
treatment for cytokine related RA
anti-TNF alpha, anti IL-6 receptor
which cytokine is dominant pro-inflammatory cytokine in rheumatoid synovium
TNF-alpha
pathogenesis of TNF-alpha RA
inflammtory cell recruitment, angiogenesis, lymphangiogenesis, –> pannus formation
matrix matalloproteases –> cartilage loss
osteoclast activation –> bone loss (osteopenia, erosions)
blood test findings in RA
increase ESR, CRP
autoantibodies
what does ACPA do in RA
causes chronic joint destruction and systemic inflammation
Xray features in RA (3)
soft tissue swelling
peri-articular oeteopenia
bony erosions
which is better scan for RA
USS
USS features of RA
synovial thickening (synovial hypertrophy)
increased blood flow (doppler signal)
can detect erosion not found on RA
why not MRI for RA
expensive
time consuming
why need aggressive pharmacological treatment for RA
suppress inflammation
pharmacological treatment for RA
glococorticoid (steroids)
DMARDs(disease modifying anti-rheumatic drug)
first line pharmacological treatment for RA
combine DMARD therapy (methotrexate+hydroxychloroquine +/or sulfasalazine) and IM or oral steroid short course
second line pharmacological treatment for RA
biological therapies eg anti-TNF alpha blockade
methods to administer steroid in RA (4)
oral prednisolone
IM methyl prednisolone
IV
Intra - articular (IA)
steroid side effects
cushing’s syndrome
what is the scoring system for RA
DAS28 score
components of DAS28 scoring in RA
number of tender joints
number of swollen joints
patient visual analogue score (VAS)
ESR/ CRP
what are some biological therapies targeting cytokines in RA
inhibit TNF-alpha and IL-6
antibodies to inhibit TNF-alpha
infliximab
adalimumab
golimumab
cetrolizumab
antibodies to inhibit IL-6 receptor
tocilizumab
sarilumab
biological therapies targeting lymphocytes
B cell depletion
block T cell co-stimulating
example of biological therapies to target B cell depletion
Rituximab (IV infusion)
example of biological therapies to target blocking T cell co-stimulation
adatacept
what is seronegative inflammatory arthritis
RF CCP antibodies not present in blood
but are immune mediated
examples of seronegative inflammatory arthritis (3)
psoriatic arthritis
reactive arthritis
ankylosing spondylitis
what is psoriatic arthritis
immune mediated disease affecting skin
where does psoriatic arthritis mainly affect
skin
extensor surfaces (elbow, knees)
some also has joint inflammation
dominant pathogenic pathway in psoriatic arthritis
IL17-IL23
what are some clinical signs of psoriatic arthritis
nail pitting
onycholysis (nail separate from nail bed)
which joints do psoriatic arthritis affect
IPJs
tendon insertions (enthesitis), can hv sausage finger
is psoriatic arthritis symmetrical
can be both
asymmetric in IPJ
symmetric in small joints
what are some manifestations of psoriatic arthritis
spinal and sacroiliac joint inflammation
oligoarthritis of alrge koints
arthritis mutilans
symmentric involvement of small joints
what is reactive inflammation
sterile inflammation followed by infection elsewhere in body
what are some common infections causing reactive
urogenital infections
gastrointestinal infection (eg salmonella)
extra-articular manifestations in reactive arthritis
enthesitis (tendon inflammation)
skin inflammation
eye inflammation
reactive arthritis can be first manifestation of which disease
HIV
Hepatitis C infection
is septic arthritis same as reactive arthritis
no
difference between septic arthritis and reactive arthritis in terms of synovial fluid culture
septic: positive
reactive: sterile
difference between septic arthritis and reactive arthritis in terms of antibiotic therapy
septic: yes, IV
reactive: no (but yes for treating underlying infection of STI)
difference between septic arthritis and reactive arthritis in terms of joint lavage
septic: yes
reactive: no
