rheum 2 Flashcards
summarise psoriatic arthritis
a seronegative inflammatory condition- associated with psoriasis
mild assocation with HLA b27
genetic and environmental factors play a role in development of disease.
rare (0.1%) in gen pop but high 6-41% in psoriasis patients. higher prevalence in northern europe.
prevents with oligoarthritis- 2-4 joints affected asymetrically.
signs and symptoms of psoriatic arthritis + some risk factors
plaques on extensor surfaces
nail dystrophy
asymetrical oligo/poly arthritis
DIPJ joints affected.
dactylitis
anterior uveitis, ulcerative colitis.
enthesopathy
can affect the spine in a simalar manner to AS
RF:
ginetics, stress- chronic or acute.
alcohol + smoking.
investigations and classification of psoriatic arthritis
no specific lab tests- CRP and ESR might be raised- but 50/50.
X-rays- errosive changes, gross joint destruction, narrowing, pencil in cup deformitiy. —— look for bone destruction and formation within the same joint.
spinal changes- but unilateral, skipping levels, as opposed to AS changes.
Classification criteria- CASPAR
Skin psoriasis: present =2, prev present = 1. none=0
nail lesions =1
dactylitis=1
RF: if -ve =1
Juxta articular bone formation=1
if 3 points- quite likely.
management of psoriatic arthritis
PTOT, stop smoking + drinking.
NSAIDS
DMARD (meth, or sulfasalazine- though sulf not effective for skin disease)
biologics- better for axial disease- TNF inhibitors are best.
less use of oral steroids as can cause psoriasis to flare.
definition, epidaemiology, aetiology + risk factors for Systemic lupus erythmatosis
an autoimmune chronic inflam connective tissue disorder- can involve skin, joints, mucous membranes, kidneys, blood vesels. autoantibodies are made to antigens - forming immune complexes - which accumulate.
type 3 hypersensitivity reaction
Epi: women of child bearing age 9:1 men.
afro-carribean/ asian
Aetiology: waste disposal- defected cells undergo apoptosis- defect + not cleared- release nuclear antigens- generation of antibodies.
RF:
genetic C4null, or variant in FC receptors
C3 deficiency.
signs and symptoms of SLE
malar/ erythematous rash
photosensitive rash
non-scarring alopecia
ulcers oral/nasally.
synovitis- more than 30 mins pain in the morning
pleurisy, effusions, rub, pericardial pain
seziures, psychosis, lethargy
thrombocytopaenia
pathophysiology of SLE
loss of B cell tolerance.
Antigen-antibody complexes then accumulate-
on renal basement mambrane
synovium
skin
small blood vessels
cell surfaces
compliment gets activated- lowering their levels in the blood stream.- releasing cytokines they promote inflammation.
Il-6 released- hepatocytes release more fibrinogen.
investigations of SLE
ANA- antinuclear antibody- most sensitive test
infirect immunofluorescence Crithidia test- checks for double straned DNA antibodies- specific but not sensitive.
Check compliment- C3 + C4 will be low. - use this to monitor disease activity.
ESR,CRP, U&E, LFT- CRP is usually low.
6/6 specific antibodies to check for
(DS-DNA, SMITH< RIBONUCLEOPROTEINS, RO, LA)
RO+LA cross placenta and can cause heart block in foetus.
Rx of SLE + prognosis
high factor sunblock, hydroxycholoroquine, topical steroids for skin
Maintenance: NSAIDS, hydroxycholoroquine,
Mild flare: low dose steds + hydroxy
mod flare- mycophenolate
severe flares- urgen high dose steds, myco, rituximab
reduce proteinurea with ACEi
prognosis-
80% survival at 15 years.
complications of SLE- anti-phospholipid syndrome
specific antibodies to
cardioliptin- a component in the inner mitochondrial membrane- which activated protein C.
by binding cardioliptin + inhibiting factor c from working factor 5 cannot be degreaded and is always active.
B2 glycoprotein antibodies- leading to activation of thrombin
lupus coagulant- bind to prothrombin- helping it be cleaved to thrombin.
to diagnose - must have antiphospholipid antibodies on 2 tests 12/52 apart
Causes: CLOT
Coagulation defecit
livedo reticularis
obstetric- recurrent misscarrage
thrombocytopaenia
management of antiphospholipid sydrome
thrombophrophylaxis- low dose aspirin 75mg
if not pregnant with thrombosis- LMWH + warfarin
pregnant with thrombosis- LMWH + aspirin
if post thrombotic event- lifelong warfarin 2-3 INR
if recurrent 3-4 INR
