1b// Rheumatoid and Other Inflammatory Arthritis Flashcards
What is arthritis?
disease of the joints
What are the 2 major divisions of arthritis?
osteoarthritis
arthritis with signs of inflammation
What is osteoarthritis?
degenerative arthritis
What are the clinical examination signs of joint inflammation?
red
hot/ warm
swelling/ fluid
What is this showing? (smth about space)
Lack of space indicates loss of articular cartilage leading to bone in contact with bone
What are the causes of joint inflammation?
- infection
- crystal arthritis
- immune mediated (autoimmune)
What are examples of joint inflammation caused by infection?
septic arthritis
Tuberculosis
What are examples of joint inflammation caused by crystal arthritis?
Gout
Pseudogout
What type of joint inflammation is secondary and primary?
secondary inflammation in response to a noxious insult
immune= primary inflammation
What type of joint inflammation is sterile and which are non-sterile?
infection= non-sterile
immune and crystal= sterile
What are the 4 major arthritis you need to know?
degenerative (osteoarthritis)
immune mediated
crystal arthritis
septic arthritis
How is the inflammation in…
degenerative (osteoarthritis)
immune mediated
crystal arthritis
septic arthritis
degenerative (osteoarthritis)= none or little
immune mediated= yes- autoimmune
crystal arthritis= yes- secondary to crystals
septic arthritis= yes- secondary to infections
How is the speed of onset with…
degenerative (osteoarthritis)
immune mediated
crystal arthritis
septic arthritis
degenerative (osteoarthritis)= slow
immune mediated= subacute
crystal arthritis= rapid
septic arthritis= rapid
What is the synovial fluid analysis like in…
degenerative (osteoarthritis)
immune mediated
crystal arthritis
septic arthritis
degenerative (osteoarthritis)= no inflammatory cells,sterile
immune mediated= inflammatory cells, sterile
crystal arthritis= inflammatory cells, sterile, crystals
septic arthritis= inflammatory cells and bacteria
What is the CRP like with…
degenerative (osteoarthritis)
immune mediated
crystal arthritis
septic arthritis
degenerative (osteoarthritis)= normal
immune mediated= high
crystal arthritis= high/ very high
septic arthritis= very high
What is the white cell count like with…
degenerative (osteoarthritis)
immune mediated
crystal arthritis
septic arthritis
degenerative (osteoarthritis)= normal
immune mediated= usually normal
crystal arthritis= usually normal
septic arthritis= high
Is septic arthritis an emergency?
yes an orthopaedic emergency
When should you assume it’s septic arthritis until proven otherwise?
acute, hot, swollen joint
What is the key investigation for septic arthritis?
joint aspiration
send fluid for Gram stain and culture
What is the management of septic arthritis?
joint washout (lavage) and IV antibiotics
lavage bc anti-b amy not reach
What are the types of autoimmune inflammatory arthritis?
Rheumatoid arthritis
Seronegative arthritis
Lupus and related disorders
How would you simply describe the clinical features rheumatoid arthritis?
Subacute/chronic Polyarthritis
Small & large joints
Symmetrical
What are the types of seronegative arthritis?
Psoriatic arthritis Reactive arthritis
Ankylosing spondylitis
IBD-associated
How would you simply describe the clinical features seronegative arthritis?
Subacute/chronic
Mono and/ or oligo large joint*
May involve spine
Asymmetrical
How would you simply describe the clinical features of lupus and related disorders?
Subacute/Chronic
Polyarthralgia (often little swelling)
Frank arthritis usually non-erosive
Describe the classification of arthritis.
What is rheumatoid arthritis?
Rheumatoid arthritis (RA) : synovial inflammation
chronic autoimmune disease
Systemic disease with extra-articular manifestations
What is the primary site of pathology of rheumatoid arthritis?
the synovium
What is the inflammation of
the synovial membrane called?
synovitis
Where is the synovium found?
joints= synovial diarthrodial joints
tendons= tenosynovium surrounding tendons
bursa
What is the sex bias and age of onset for rheumatoid arthritis?
F:M = 2:1
30s-50s
What are the key features of rheumatoid arthritis?
Chronic arthritis
Polyarthritis
Pain, swelling and early morning stiffness in and around joints
May lead to joint damage and destruction - ‘joint erosions’ on radiographs
What is normally detected in the blood with rheumatoid arthritis? And give examples.
Auto-antibodies usually detected in blood
such as rheumatoid factor and anti-citrullinated protein antibodies (ACPA)
How do you estimate the contributions of genetic vs environment for diseases?
What is the environmental aetiology of rheumatoid arthritis?
Smoking
Microbiome
Porphyromonas gingivalis
Poor oral health
Why does smoking cause rheumatoid arthritis, and give an example of something else that does this?
Smoking -> citrullination of proteins in lung epithelium P. gingivalis can also cause citrullination
Is rheumatoid arthritis genetic?
mixture of genes and environment
seen from twin studies
RA concordance in twins 1 : monozygotic ~15% dizygotic ~4%
What is the strongest genetic risk factor for rheumatoid arthritis?
HLA-DR
especially HLA-DR(beta)1
and HLA-DR4 (not as much)
What 2 synergistically increase risk of RA?
HLA-DRb chain amino acids 70-74 (‘shared epitope’).
Smoking & shared epitope synergistically increase risk
How many genetic loci found by the genome wide association studies contribute to RA risk? And give examples.
100 other genetic loci (polygenic)
E.g. PTPN22, IL6R
How would you describe the effect of a risk allele for having RA?
modest effect
Cumulative genetic burden rather than any one variant determines risk
What are the classes of HLA?
HLA class 1= HLA A, B, C
HLA D= class 2