Rheumatoid Arthritis Flashcards
Define Rheumatoid ARthritis
an autoimmune condition leading to inappropriate immune system activity causing synovial and connective tissue inflammation
Patholgy RA. Cause?
Chronic inflammation growth of tissue (pannus) loss of bone and cartilage (bone revrsible, cartilage not)
Triggered by genetics and by a “stochastic” event
Consequences of inflammation
Loss of cartilage
Formation of scar tissue
Ligament laxity
Tendon contractures – joint to twist into locked position
RA Symptoms
Symmetrical joint pain and stiffness >6 weeks
Muscle pain
May have fatigue, weakness, low-grade fever, appetite decrease
Joint tenderness with warmth and swelling over affected joints
Rheumatoid nodules may develop (collection of fibrous scar tissue) – not painful unless effecting a nerve
Most commonly a rapid onset starting in peripheral joints
Difference between RA and Osteo
Joint Damage
Occurs early in the course of RA
30% of patients have bone erosion at time of diagnosis
Damage is irreversible
Functional loss follows
RA can also effect the….
Blood Vessels
Lungs
Eyes
Heart
Muscle
Bone
Skin
Hematologic abnormalities
Blood vessels
Rheumatoid vasculitis
Occurs with severe, long-standing RA
Leads to substantial morbidity
Can affect any blood vessel
Symptoms experienced depend on affected vessels
Only treatment: Aggressive treatment of RA itself
Lungs
Pleuritis, pleural effusion, fibrosis, pulmonary nodules
Drugs used to treat RA may also impact lung function
Eyes
Episcleritis, scleritis, uveitis and iritis
Painful, visual acuity loss
Heart
Pericarditis, myocarditis
Increase risk of CAD, heart failure and atrial fibrillation
Muscle
Generalized weakness and pain
From synovial inflammation, myositis, vasculitis
Steroid-induced
Bone
Osteopenia common
Local bone loss around affected joints
Skin
Rheumatoid nodules
Ulcers
Steroid-induced changes
Hematological
Anemia – not iron; anemia of. Chronic dx (chronic inflammation) – treat the inflammatory pathway
CANSOME ACHIEVE REMISISON IN RA?
Yes it is sposisble
Achieve remission or low disease activity
REMISSION DEFINITION RA
Tender/swollen joint count <1
A measure of function based on the Health Assessment Questionnaire (HAQ)
CRP score <1
A physician global assessment <2
A patient assessment of global disease activity (PtGA) <2 – considering how much it effects there QOL
GENERAL PRINCIPLE SOF RA TREATMENT
Early recognition and diagnosis
Significant damage occurs in first two years of disease
Early use of DMARDs
Start within 3m of diagnosis
Depending on severity, treat aggressively
Concept of “tight control”
Treat until remission or low disease activity
Quickly treat exacerbations
Aggressively add DMARDs or early switch
Adjunct NSAID / steroids
Frequent reassessment
4) Responsible NSAID and glucocorticoid use
Reduce / discontinue as disease enters remission
NON-PHAR TX
Patient education
Rest important, but balance with activity
Reduce joint stress with RA friendly tools
Occupational and physical therapy
Diet / weight loss
Surgery
MAin RA Drug Classes
Role of Dmards
Slow onset of action
Controls symptoms
May delay or stop progression of disease
Requires regular monitoring
DMARD Examples
Hydroxychloroquine
Sulfasalazine
Methotrexate
Leflunomide
Hydroxychloroquine MOA
Inhibits neutrophils and chemotaxis; impairs complement system
- down stream effects of inflammatory response
Sulfasalazine MOA
Prodrug metabolized into 5-ASA and sulfapyridine
Modulates mediators of inflammatory response; may inhibit TNF
Immune system
Methotrexate MOA
Anti-folate less DNA synthesis, repair, cellular replication and immune response
Often supplement witj folic acid
Leflunonamide MOA
Inhibits pyrimidine synthesis, leading to anti-inflammatory effects
Modulates many signaling pathways
Onset DMARDS
Hydroxychloroquine – 2-6 months
Sulfasalazine - 2-3 months
Methotrexate – 1-2 months
Leflunomide – 1-3 months
Methotrexate DOse
Methotrexate – 7.5 to 25mg PO weekly
Titrate to target in most cases
Renal dosing: eGFR 10 – 50ml
May initiate at target dose in select patients
Target Dose: 15 mfg per week
Titrate: 7.5 mg per week, increase by 2.5-5 Q 1 month
Can be used in dialysis: reduce all doses by 50%
