Rheumatology Flashcards
What is the definition of Rheumatoid Arthritis (RA)?
Symmetrical inflammatory arthritis affecting mainly the peripheral joints which if untreated can potentially lead to joint damage and irreversible deformities
Who is more commonly affected by rheumatological conditions, men or women?
Women (beaut.)
What mediates RA?
A major histocompatibility complex class II allele human leukocyte antigen: HLA-DR4
What is the main structure involved in RA?
the synovium (lines joint capsules and tendon sheaths)
True or False, the first two joints of the spine, C1/C2 can be affected by RA
True, because they are lined by synovium
Which joints are preserved in synovitis of RA?
Distal interpharyngeal joints
What defines RA as early RA?
Less than 2 years since symptom onset
What tests should be done in RA?
Blood testing, inflammatory markers, autoantibodies and imaging (x-rays of hands and feet and US for signs of synovitis)
True or False, diagnosis of RA is dependent on detection of auto-antibodies
False, it is a clinical diagnosis
Which auto-antibodies are associated with RA?
Rheumatoid factor (not as specific) and Anti-CCP (very specific)
Which score is used to assess disease activity in RA, and what are the classifications based on results?
DAS 28 score ( >5.1 = active disease, 3.2-5.1 Moderate disease, 2.6-3.2 = low disease activity, <2.6 = remission)
What is the primary treatment for RA?
DMARDs: Methotrexate, with NSAIDs and steroids only as adjuncts in early stages while waiting for DMARDs to take effect
What are the first and second line DMARDs, and other options in RA?
Methotrexate and Sulfasalazine (alternatively Hydroxychloroquine, Leflunomide and combination therapy)
Why must a baseline CXR be taken with Methotrexate?
Risk of pneumonitis (allergic reaction in the lung)
What risks are there with Methotrexate?
Pneumonitis, liver function derangement, bone marrow suppression, tetrogenic effects
What is the starting dose of Methotrexate in RA?
15mg/week with rapid escalation until state of clinical remission is achieved (max 25mg/week)
What are examples of biologic agents?
Anti TNF agents primarily: Infliximab, Etanercept, Adalimumab, Certolizumab, Golimumab (or T cell receptor blockers, B cell depletes, IL-6 blockers or JAK 2 inhibitors)
What are the guidelines for biologic agent use in RA?
- Used when failure to respond to 2 DMARDs including Methotrexate and DAS 28 greater than 5.1 on two occasions 4 weeks apart.
- Methotrexate therapy is co-prescribed.
- Screen for latent or active TB , Hep B, C, HIV, Varicella zoster.
- Avoid live attenuated vaccines.
What are some complications of untreated RA?
Swan necking, Boutonnière’s, calluses, atlante-axial subluxation
What is the definition off Osteoarthritis?
Progressive degenerative condition affecting joints due to gradual thinning of cartilage, loss of joint space and formation of bony spurs (osteophytes) - essentially ‘wear and tear’
What is the pathogenesis of OA?
There is loss of matrix, release of cytokines including IL-1, TNF and mixed metalloproteinases as well as prostaglandins by the chondrocytes. Fibrillation of the cartilage surface and attempted repair with osteophyte formation then occurs (overstimulation of the bone)
What are some of the clinical signs of OA?
Heberdens nodes (bony enlargements at DIPs), squaring of thumb, osteophytes, effusions, crepitus at joints, varus/valgus deformities, restricted movement
What tests are done in OA?
Inflammatory markers, X-ray
** What are the main differences between RA and OA?
.