Seronegative Arthritis Flashcards
define poly-arthritis
inflammation of more than 4 joints
define oligoarthritis
inflammation of 2 or 3 joints
mono is jusy one
what is acute poly-arthritis
less than 6 weeks infection related: bacterial, viral, post-infectious reactive early autoimmune metabolic: crystal-induced arthritis) neoplastic: leukemia
what is chronic poly-arthritis
more than 6 weeks
infection: hep c
immune: RA, seronegative spondyloarthopathy, connective tissue diseases
metabolic: crystal-induced arthritis
degenerative: OA
what are features of spondyloarthropathies
rheumatoid factor & ANA neg axial arthritis (sacroiliitis, spondylitis) peripheral (asymmetric, LE > UE) oligo/poly-arthritis, large joints young at onset (<40) HLA-B27 ENTHESITIS may/may not have high ESR/CRP
what is enthesitis
inflammation at fibrocartilage insertionsof tendons, fascia or ligaments into bone
describe ankylosing spondylitis (AS)
symmetrical sacroiliitis ascends from lumbar to cervical progressive bony fusion M>F onset late teen - early 20s high in Native Americans, low in black
clinical features of AS
alternating buttock pain (SI joints) morning stiffness of back (>1hr) worse w rest, improve w exercise pain >3mo patient <40yr old 1/3 w peripheral joint involvement
PE for AS
tender SI joints/spine/entheses
decreased ROM in all planes
lumbar: reduced Schober’s test)
cervical: increased occiput-to-wall distance
decreased chest expansion
question mark posture
(decreased lumbar lordosis, increased thoracic kyphosis, decreased cervical lordosis)
describe Schober’s test
mark dimples of venus
mark 10cm above
measure between marks after bending down
should increase more than 15cm
describe occiput-to-wall
patient stand close to wall
should be 0 distance between back of head to wall
XR features of AS
sacroiliitis: erosion and sclerosis of joint margins, late (bony fusion, loss of sclerosis)
squaring of vertebral bodies (not concave)
symmetrical syndesmophytes (ossification of longitudinal spinal ligaments)
sclerosis and fusion of facet joints
osteoporosis
end stage: bamboo spine
extra-articular features of AS
Enthesitis (insertion of achilles, plantar fascia)
iritis (blurriness, scarring, vision loss)
cardiac involvement
pulmonary fibrosis
pathogenesis of AS
HLA-B27 codes for class I MHC
believed to bind arthritogenic peptides from gut bacteria
bacterial peptides resemble self-antigens (molecular mimicry) –> T-cells cross react and initiate inflammation
need both bowel inflammation and HLA gene
is HLA-B27 a good screening test?
no
is AS 100% genetic
no
twin studies, monozygotic twins 63% concordance rate
prognosis of AS
85% remain employed
15% sig disability after 20-40yrs
describe enteropathic arthritis
~5% of patients w IBD indistinguishable from primary AS M = F usually follows onset of bowel disease no correlation bw bowel and joint flares, but treat bowel, treat joint
describe psoriatic arthritis (PA)
15-30% psoriasis pt arthritis before skin in 25% no correlation bw skin and joint flares 85% have psoriatic nail changes M = F
what are subgroups of PA
asymmetric oligoarthritis RA-like polyarthritis AS-like spondyloarthritis DIP joint arthritis mutilans (severe destruction)
in what diseases is dactylitis seen (sausage)
gout
reactive arthritis
psoriatic arthritis
how to differentiate psoriatic vs. RA
skin and nail changes RF neg no rheumatoid nodules DIP joint inflammation uncommon in RA sacroiliitis on XR usually fewer joints, asymmetry new bone formation in PA
describe pencil in cup erosion
distal phalynx forms ‘cup’ adjacent bone worn off to create ‘pencil’
epidemiology of reactive arthritis
sterile arthritis 1-4wk AFTER infection 20's, M > F follow infectious diarrhea (salmonella, ersinia, shigella, campylobacter) chlamydia treat w minocycline, doxycycline bacteria not identified (too late)
triad of reactive arthritis
Reiter’s syndrome
urethritis
conjuctivities
arthritis
acute, asymmetric, oligoarthritis
dactylitis and achilles enthesitis
extra-articular features of reactive arthritis
oral ulcers
circinate balanitis
keratoderma blenorrhagicum (palms/sores)
nail changes: onycholysis, subungual hyperkeratosis, yellowing
asymptomatic bowel inflammation
prognosis of reactive arthritis
lasts 2-3mo
up to 20% have chronic
Tx for spondyloarthropathies
eduction, PT/OT
NSAIDs, intra-articular steroids
DMARDs (sulfasalazine, methotrexate, leflunomide)
DMARDs not useful for spinal arthritis
Tx for ankylosing spondylitis
anti-TNF (for psoriatic, spine, peripheral joints)
biologics such as Ab against IL-17, IL-12/IL-23
