Rheumatoid arthritis Flashcards
What is rheumatoid arthritis?
Autoimmune disease which results in chronic joint inflammation
What can untreated rheumatoid arthritis lead to?
- Joint destruction
- Deformity
- Loss of function
- Extra articular complications
What is the pathophysiology of rheumatoid arthritis?
- Genetic predisposition (HLA DR4) plus an environmental precipitant
- Immune system acting against own immune system and joints
What is the usual age of onset of rheumatoid arthritis?
between 30 and 60
In which populations is rheumatoid arthritis more aggressive?
- African American
* Hispanic
What are the symptoms of rheumatoid arthritis?
- Pain
- Stiffness (early morning and joint gelling)
- Swelling
- Tends to be smaller joints over larger joints and also tends to be symmetrical
- Persistent
What are the signs of rheumatoid arthritis?
- Synovitis (joint swelling)
- Deformity (not early stage)
- Rheumatoid nodules
What are the deformities seen in rheumatoid arthritis?
- Swan neck
- Boutonniere
- Z-thumb
- Ulnar deviation
What should you consider as a differential diagnosis in rheumatoid arthritis?
- Polyarticualr gout
- Psoriatic arthritis
- osteoarthritis
- SLE
What investigations should be carried out in suspected rheumatoid arthritis?
Lab non specific:
•CRP/ESR
•FBC
•Bone/urate
Lab specific:
•Immunology
Imaging:
•Plain radiograph (X ray won’t show early stages)
•Ultrasound
•MRI
What antibodies can you test for in rheumatoid arthritis?
- Rheumatoid factor
* CCP Ab
What is rheumatoid factor?
- IgM antibody
- Directed against the Fc portion of the IgG antibody
- Found in a multitude of conditions
What is the specificity and sensitivity of testing for rheumatoid factor in rheumatoid arthritis?
- Sensitivity = 70%
* specificity 80-85%
In what conditions is rheumatoid factor found?
- Rheumatoid arthritis
- SLE
- bacterial endocarditis
- Sjogren’s
- Primary biliary cirrhosis
- Hepatitis B and C
- Increasing age
What is CCP Ab?
- Inflammation leads to cellular damage
- Enzymatic process leads to the conversion of arginine residues to citrulline
- Alteration of shape creates a foreign antigen from self anti citrullinated cyclic peptide antibodies
What is the sensitivity and specificity of CCP Ab?
- Sensitivity: 66%
* Specificity: 90%
What is the name of the classification criteria for Rheumatoid Arthritis and what score fulfils the classification criteria for rheumatoid arthritis?
EULAR, a score of 6 or more
What are the first changes seen on X ray in patients with rheumatoid arthritis?
- Peri-articular osteopenia
* Soft tissue swelling
What are the late changes seen on imaging in patients with rheumatoid arthritis?
- Erosion
- Joint destruction
- Subluxation
What are the aims of the treatment of rheumatoid arthritis?
- Reduce inflammation
- Maintain joint function
- Prevent progression
Explain initial therapy for patients with rheumatoid arthritis
- Aims to reduce inflammation
- NSAIDs - ibuprofen/naproxen/diclofenac
- COX-2 inhibitors - Etoricoxib
- Steroids - short term - oral prednisolone, intramuscular or intra-articular depomedrone
What are the first line drugs in rheumatoid arthritis?
- cDMARDs (conventional disease modifying anti rheumatic drugs) should be offered within 3 months of symptom onset
- Methotrexate
- Leflunomide
- sulfasalazine
- Hydroxychloroquine if mild or if palindromic disease
What is methotrexate?
Folate antagonist
How often is methotrexate taken in RA?
Once weekly
What are the side effects of methotrexate?
- Mucosal effects: mouth ulcers
- GI effects: nausea
- Rare: pneumonitis or hepatitis
What needs to be monitored if a patient is on methotrexate?
FBC and LFTs
When is methotrexate contra indicated?
In pregnancy as it is teratogenic
What is sulfasalazine?
cDMARD that is immunomodulatory with several actions including against T and B cells and folate
How often is sulfasalzine taken for RA?
Once daily
What are the side effects of sulfasalazine?
- GI
- Headache
- Rash
- Normally avoided if you gradually increase the dose
What do you need to monitor in patients on sulfasalazine?
- FBC
- U&Es
- LFTs
What is hydroxychloroquine?
blocks toll like receptors on plasmacytoid dendritic cells (that release IFN), thus reducing dendritic cell activation
How often is hydroxychloroquine taken for RA?
Daily
What are the side effects of hydroxychloroquine?
- Headache
- Nausea
- Muscle pain
- Rash
What do you need to monitor in patient on hydroxychloroquine?
Ocular monitoring to look for retinopathy
What is used for disease monitoring in RA?
DAWN
What must you do before starting a patient on a bDMARD for RA?
- Screen for viral hepatitis, HIV, varicella,
- ensure vaccination against influenza and pneumococcal infection
- Ensure no contraindications
- Monitor for infection, malignancy, check bloods (FBC and LFT) throughout treatment
What are the contraindications to bMARDs?
- Active infection
- Active or latent TB
- Pregnancy
