Intro to Rheumatology Flashcards
What is a joint?
Where 2 bones meet
What are tendons?
Chords of strong fibrous collagen tissue attaching muscle to bone
What are ligaments?
Flexible fibrous connective tissue which connect two bones
How many cells deep is the synovium?
1-3 cells
What cells does the synovium contain?
macrophage like phagocytic cells and fibroblast cells that produce hyaluronic acid
What is synovial fluid rich in?
Hyaluronic acid
What is articular cartilage formed of?
Type II collagen and proteoglycan (aggrecan)
What are the 3 big components of synovial joint?
Synovium, synovial fluid and articular cartilage
Define arthritis
Disease of the joints
What are the 2 main types of arthritis?
Osteoarthritis and inflammatory
What is osteoarthritis?
A degenerative type of arthritis
Define inflammation
A physiological response to deal with injury or infection
What are the clinical signs of inflammation?
Rubor (red) Dolor (pain) Calor (hot) Tumor (swelling) Loss of function
What physiological, cellular and molecular changes occur with inflammation?
Increased blood flow
Migration of white blood cells (leucocytes) into the tissues
Activation/differentiation of leucocytes
Cytokine production
What are the 2 causes of joint inflammation?
Crystal arthritis and immune mediated
What are the types of crystal arthritis?
Gout and pseudogout
What is gout?
A syndrome caused by deposition of urate (uric acid) crystals that causes inflammation
What are crystals in gout made of?
Urate (uric acid)
What is the main risk factor for gout?
Hyperuricaemia (high uric acid levels)
What are some causes of hyperuricaemia?
Genetic tendency Increased intake of purine rich foods Reduced excretion (kidney failure)
What are tophi?
Aggregated deposits of mono sodium urate in tissue, they are white looking
What joint does gouty arthritis most commonly affect?
Metatarsophalangeal joint of the big toe (‘1st MTP joint’)
How does gout come on and how is it characterised?
Abrupt onset
Extremely painful
Joint red, warm, swollen and tender
Resolves spontaneously over 3-10 days
What is pseudogout?
A syndrome caused by deposition of calcium pyrophosphate dihydrate (CPPD) crystal deposition crystals that leads to inflammation
What are crystals in pseudogout made of?
Calcium pyrophosphate dihydrate (CPPD)
What are risk factors for pseudogout?
Background osteoarthritis, elderly patients, intercurrent infection
How is acute pseudogout managed?
colcihine, NSAIDs, Steroids
How is chronic pseudogout managed?
Allopurinol
What sample can be examined in gout and pseudogout?
Synovial fluid
What shape are crystals in gout?
Needle
What shape are crystals in pseudogout?
Brick
What is the result for polarising light microscopy in gout?
Negative
What is the result for polarising light microscopy in pseudogout?
Negative
Is rheumatoid arthritis chronic or acute?
Chronic
How is rheumatoid arthritis characterised?
Pain, stiffness and symmetrical synovitis (inflammation of the synovial membrane) of synovial (diarthrodial) joints
What is abnormal is rheumatoid arthritis?
The synovial membrane, it becomes proliferated due to neovascularisation, lymphangiogenesis and inflammatory cells
What happens to the cytokine balance in rheumatoid arthritis?
There is an excess of pro-inflammatory vs. anti-inflammatory cytokines
What is the function of a healthy synovial membrane?
Maintenance of synovial fluid
What is the consistency of synovial fluid?
Viscous
What is seen in rheumatoid arthritis at the joint?
Synovitis
Bone erosion
Pannus (proliferated mass of synovial membrane)
Cartilage degradation (joitn space narrowing)
What is the main pro inflammatory cytokine that is present in excess in rheumatoid arthritis?
TNF alpha
What cytokine is often inhibited when treating rheumatoid arthritis and how?
TNF alpha, achieved through parenteral administration (most commonly sub-cutaneous injection) of antibodies or fusion proteins
What is polyarthritis?
Swelling of the small joints of the hand and wrists, it is symmetrical, more prominent in the early morning
What extra articular disease can occur in rheumatoid arthritis?
Rheumatoid nodules
Vasculitis
Episcleritis
What factor may be detected in blood in rheumatoid arthritis?
Rheumatoid factor= autoantibody against IgG
What is the pattern of joint involvement in rheumatoid arthritis?
Symmetrical Polyarthritis (affects multiple joints) Affects small and large joints
What joints are commonly involved in rheumatoid arthritis?
Metacarpophalangeal joints (MCP) Proximal interphalangeal joints (PIP) Wrists Knees Ankles Metatarsophalangeal joints (MTP)
What are the common extra articular features in RA?
Fever, weight loss, subcutaneous nodules
What are the uncommon extra articular features in RA?
Vasculitis
Ocular inflammation e.g. episcleritis
Neuropathies
Amyloidosis
Lung disease – nodules, fibrosis, pleuritis
Felty’s syndrome – triad of splenomegaly, leukopenia and rheumatoid arthritis
What are subcutaneous nodules associated with in RA?
Severe disease
Extra-articular manifestations
Rheumatoid factor
What is a typical position for a subcutaneous nodule in RA?
Ulnar border of forearm (near elbow)
What are the 2 antibodies found in RA?
Rheumatoid factor
Antibodies to citrullinated protein antigens (ACPA)
What do rheumatoid factor antibodies target?
Fc portion of IgG
What type of antibody is rheumatoid factor?
IgM
What enzymes mediate ACPA in RA?
Peptidyl arginine deiminases (PADs)
Arginine becomes citrulline
What is the treatment goal in RA?
Prevent joint damage
How does ideal treatment of RA start and progress?
Early symptom recognition and referral
Prompt initiation of treatment
Aggressive treatment to allow early suppression
What is the main class of drugs used in RA? What ones are used first line?
DMARDs, 1st line is methotrexate in combination with hydroxychloroquine or sulfasalazine
What is the second line treatment for RA?
Biological therapies
What are biological therapies (in ref to RA)?
Proteins (usually antibodies) that specifically target a protein such as an inflammatory cytokine
What are the 4 ways biological therapies can be used in RA?
Inhibition of tumour necrosis factor-alpha (‘anti-TNF’)
B cell depletion
Modulation of T cell co-stimulation
Inhibition of interleukin-6 signalling
Are autoantibdies found in akylosing spondylitis?
No
What does ankylosis refer to in akylosing spondylitis?
Spinal fusion
What is the common demographic for akylosing spondylitis?
20-30yr old males
How does akylosing spondylitis present clinically?
Lower back pain + stiffness (early morning, improves with exercise) Reduced spinal movements Peripheral arthritis Plantar Fasciitis Achilles Tendonitis Fatigue Hyper extended neck Loss of lumbar lordosis Flexed hips and knees
What is found in bloods in ankylosing spondylitis?
Normocytic anaemia
Raised CRP, ESR
HLA-B27
What is found on MRI in ankylosing spondylitis?
Squaring Vertebral bodies Romanus lesion Erosion Sclerosis Narrowing SIJ Bamboo Spine (vertebrae start to fuse together) Bone marrow oedema
How is ankylosing spondylitis managed?
Physiotherapy
Exercise regimes
NSAIDs
Peripheral joint disease – DMARDs
What is psoriatic arthritis?
Joint inflammation in those with psoriasis
How does psoriatic arthritis differ from RA?
It is seronegative, there are no autoantibodies
How does psoriatic arthritis present clinically?
Classically asymmetrical arthritis affecting IPJs, there can also be symmetrical small joint involvement, spinal and sacroiliac joint inflammation, oligoarthritis of large joints, arthritis mutilans
How is psoriatic arthritis managed?
DMARDs – methotrexate
What must be avoided in psoriatic arthritis and why?
Oral steroids due to risk of pustular psoriasis due to skin lesions
What is reactive arthritis?
Sterile inflammation in joints following infection especially urogenital and gastrointestinal infections
What are important extra articular manifestations of reactive arthritis?
Enthesitis (tendon inflammation)
Skin inflammation
Eye inflammation
What may reactive arthritis be a first manifestation of?
HIV or hepatitis C infection
What demographic does reactive arthritis commonly affect?
Commonly young adults with genetic predisposition (e.g. HLA-B27) and environmental trigger (e.g. Salmonella infection)
How is reactive arthritis managed?
Usually is self limiting but can be managed with NSAIDS or DMARDs if required
What is reactive arthritis distinct from?
Septic arthritis (infection in joints)
What is SLE?
A multi-system autoimmune disease with multi-site inflammation (can affect almost any organ)
What are autoantibodies in SLE directed against?
Components of the cell nucleus (nucleic acids and proteins)
What are the 2 clinical tests for autoantibodies in SLE?
- Antinuclear antibodies (ANA):
High sensitivity for SLE but not specific.
A negative test rules out SLE, but a positive test does not mean SLE. - Anti-double stranded DNA antibodies (anti-dsDNA Abs):
High specificity for SLE in the context of the appropriate clinical signs.
Which gender does SLE affect more commonly? By how much?
More females (9:1)
What demographic does SLE affect more commonly?
15 - 40 yrs
Increased prevalence in African and Asian ancestry populations
What is a common rash in those with SLE?
Butterfly/malar rash
What condition does symmetrical arthritis of the hand and wrists and morning stiffness indicate?
Rheumatoid arthritis
What tests are ordered if rheumatoid arthritis is suspected?
Rheumatoid factor X ray Lupus antibody (to exclude) CRP ESR Bloods (to check for normocytic anaemia)
If psoriatic arthritis is suspected, what other signs can you look for?
Other skin manifestations of psoriasis
Symmetry
Check ICPs
Is there saco-iliac joint inflammation?
