Week 224 - Rheumatoid Arthritis Flashcards
Define rheumatoid arthritis
Chronic Systemic Inflammatory Disorder of unknown trigger
Uncontrolled inflammation resulting in joint destruction.
What is the primary site of pathology in RA?
The synovium
What is Pannus formation?
Thickened, inflammed synovium. Causes damage to bone, cartilage and sometimes ligaments in and around the joint
What are the key details in the epidemiology of RA?
Race - worldwide
Female:Male > 3:1
Age - any - peak = 35-45
Smoking - clear link to incidence and increased severity
Genetics - certain influence (HLA-DR4 and PTPN22)
How can RA present?
Many different possible clinical manifestations:
- gradual onset - small peripheral joints, usually symmetrical
- acute, abrupt onset polyarthritis
- slow or acute monarticular presentation
- palindromic rheumatism
- local or systemic extra-articular features
What will typical RA histories contain to make it different to OA?
Usually small joints (MCP, proximal IP - NOT usually distal IP joint)
Worst in the morning
Improves with activity over a few hours
What is the most common progression pattern in RA patients?
75% experience ongoing joint pain with flare ups
Describe a “Swan-neck deformity”
Hyperextension of PIP joint with
Fixed flexion at DIP
Describe “Boutonnaire” deformity
Fixed flexion at PIP joint with
Hyperextension at DIP joint
What 3 signs are you likely to see on a hand x-ray in the presence of RA?
Periarticular osteopenia - areas of bone appear darker
Periarticular erosions - distal heads of metacarpals often
Reduced joint spaces
According to the ACR Classification criteria 1989 how many of the 7 criteria must be present to diagnose RA?
=/> 4
What causes the ulnar deviation seen in more severe progressions of RA?
Reduced integrity of the MCP joints - due to erosion for example - subluxation occurs
What combination of methods are usually required to diagnose RA?
History and examination
Bloods: ESR, CRP, Rheumatoid Factor, anti-CCP (cyclic citrullinated peptide)
Imaging: x-ray, USS/MRI - synovitis
Which of the various blood tests is more useful in the diagnosis and why?
Useful: CRP (more so than ESR) and Anti-CCP (more specific to RA than rheumatoid factor)
Arguably rheumatoid factor - present in ~80% with but also ~5% general population
What exactly is rheumatoid factor a measure of?
It detects the level of IgM antibody
Why is ESR not a very useful blood test result in the diagnosis of RA (and many other conditions!)?
Too many other factors effect levels of ESR including:
Age
Renal function
Anaemia
There are many extra-articular manifestations of RA. What are the constitutional manifestations alone?
Fever, fatigue and weight loss
What percentage of Rheumatoid Factor +ve patients are thought to experience rheumatoid nodules?
~20% (rare in RF -ve pts)
Can remove but often return and have little effect besides being an irritation
What pulmonary manifestations can occur with RA?
Pulmonary manifestations are frequent but often subtle
- pleural effusions
- interstitial fibrosis
- primary nodules from RF
What cardiac / CVS manifestations can occur with RA?
Vasculitis - severe RA; venous HTN and ulcers
- increased risk of IHD
- pericarditis / pericardial effusions
- coronary vasculitis
- non-specific myocarditis
- valvular disease *similar CVS disease risk to diabetics
What ocular manifestations can occur with RA?
- Episcleritis
- Scleritis - usually effects vision, painful > treat aggressively or perforation can occur
What neurological manifestations can occur with RA?
- Entrapment e.g. Carpal Tunnel
- Atlanto-axial subluxation > cervical myelopathy
- Mononeuritus multiplex
- Central NS vasculitis
What haematological manifestations can occur with RA?
- Anaemia (chronic disease - bone marrow suppression - NSAIDs and DMARDs)
- Thrombocytosis (hence increased risk of IHD)
- Rarely lymphadenopathy and Felty’s syndrome
What is Amyloidosis?
A RARE condition but one to be aware of!
Result of chronic inflammation: increased serum amyloid-A protein (SAP) - every organ may be involved
