11. Rheumatology: rheumatoid arthritis & systemic lupus Flashcards
LOs
autoimmune or not auto-immune disorder?
- Rheumatoid arthritis (RA)
- Sjogren’s Syndrome (SS)
- Systemic lupus erythematosus (SLE)
- Scleroderma
- osteoarthritis
AUTOIMMUNE
- Rheumatoid arthritis (RA)
- Sjogren’s Syndrome (SS)
- Systemic lupus erythematosus (SLE)
- Scleroderma
NOT-AUTOIMMUNE
5. osteoarthritis
- Rheumatoid arthritis (RA)
- Sjogren’s Syndrome (SS)
- Systemic lupus erythematosus (SLE)
- Scleroderma
- aetiopathogenesis of these disorders
- Associated with MHC:
- Immunological associations
1
* Unknown cause
* Combination of genetic and environmental factors leading to breakdown of immune tolerance
2
- strong HLA association
- Rheumatoid Arthritis (RA): HLA-DR4 (more frequent in smokers, 20-40x more risk)
- Systemic Lupus Erythematosus (SLE): HLA-DR3, complement components
- Progressive systemic sclerosis (PSS): HLA-DR3
3
* serology often positive for a variety of autoantibodies
- Histology shows evidence of immune involvement
autoantibodies to know for each autoimmune disease
RA: :
- RF (Rheumatoid factor) non-specific (one of the
most common in RA, but not exclusive to RA,
found in other inflamm + infectious diseases)
- Anti CCP (anti-citrullinated protein antibodies)
95% specific o RA)
SLE: ANA + dsDNA (antinuclear antibodies)
PSS: Scl 70
Sjogren’s: ENA (Ro, La) RF
NOTE
- PSS = progressive systemic sclerosis
- ENA = extractable nuclear antibodies
RHEUMATOID FACTORS
- what are rheumatoid factors?
- what autoimmune disorders is RF found in?
1
- autoantibodies directed to IgG antibodies
- can be IgG or IgM
- May be any isotype but is directed to Fc IgG
2
* RA 80%
* Sjogren’s 70%
* Cryoglobulinaemia >90%
RHEUMATOID ARTHRITIS clinical features
- % of pop
- F:M
- what is it?
- symptoms
- signs
1
1% population
2
F:M 2.5:1
3
- Symmetrical polyarthritis often starts in hands and wrists
- Systemic disease which may have extra-articular involvement
4
Symptoms
~ pain
~ swelling
~ morning stiffness
~ malaise
~ non-articular symptoms
5
Signs
~ Swelling
~ warmth (erythema)
~ tenderness
~ limited movement
~ deformity
IMAGE 1
- early stage of RA
- erythema over knuckles
- swelling - 2nd and 3rd joints
- otherwise they look relatively normal
IMAGE 2
- advanced rheumatoid changes
- fingers pointing outwards (ulnar drift)
- MCP swelling
- z shapes thumb
IMAGE 1
- dislocation on sole of feet
IMAGE 2
- toes are no longer able to touch ground
ANATOMY OF RA JOINT VS HEALTHY JOINT
HEALTHY JOINT
- normal synovial membrane
- lined by synoviocytes
- wide joint space
RA JOINT
- thickening of synovial membrane
- overgrowth of synoviocytes
- influx of inflamm cells
- each of these prod cytokines - stimulating inflam
- forming planus
- panus activates osteoclast to eat away at bone
- this removes + damages’ cartilage overlying the bone
- causes inflam of overlying soft tissues
- damages ligaments and structures supporting itself
- damages joint itself
SUMMARY
*Granulation tissue forms at the edges of the synovial lining (pannus)
* The synovium thickens (pannus)
* Then Complement activation and release of destructive enzymes occurs
*Cytokines and chemokines attract and accumulate immune cells, i.e. activated Tand B cells, monocytes and macrophages in the joint space
* Cytokines stimulate inflammation
* Panus activates osteoclasts to eat away at bone
*Osteoclast production results in:
~ degradation of bone tissue
~ remove + damages’ cartilage
overlying the bone
~ ligaments and structures
supporting itself being damaged
~ joint itself being damaged
- loss of cartilage
- loss of bone
Complications of RA
§ Rheumatoid nodules
= inflamm in subcutaneous tissues = same type of
inflamm that occurs in plannus
- can occur, hands forearm, lungs, etc
§ Tendon rupture
- leads to subluxation
§ Normochromic, normocytic anaemia
§ Nerve entrapment e.g. median nerve
- (damage at writs causes this)
§ Vasculitis
- inflamed blood vessels
- can lead to gangrene occur
§ Atlanto-axial subluxation
- important for anaesthetists to assess patients
as mishandling of neck can lead to this + spinal
cord entrapment in patients with RA
§ TMJ can be affected
§ Eye complications
SPLIT PREVIOUS PIC IN 2???
Treatments specific for RA
- Analgesia (e.g. NSAIDs reduce pain and swelling)
- meds can cause comp - bad for kidney, can
cause GI bleeding, iron deficiency) - DMARDs (disease modifying anti rheumatic drugs) especially methotrexate, hydroxychloroquine for mild
to moderate
- can cause infection - TNFa blockade e.g. Infliximab, Etanercept
- Anti-B cell monoclonal ab e.g. rituximab
(patients given aggressive treatment early on to prevent RA comp so patients at higher risk of comp from medicines than RA
Relevance to dentistry
§ Hand deformity – oral hygiene, blister packs
§ Carpal tunnel syndrome
§ Atlanto-axial subluxation during GA
§ TMJ dysfunction
§ Sjogren’s syndrome
- dryness in mouth, eyes, genital tract
§ Anaemia
- relevance = healing capacity, anesthesia
capacity
- type??
§ Complications of systemic treatment
- infection
RA KEY POINTS
- Common autoimmune disease
- The joint complications are not usually seen nowadays due to improved therapy
- Multisystem disease – remember the extra-articular complications
- Remember the DMARD /immunosuppressive treatment may impact your dental care
SJOGREN’S SYNDROME
primary or secondary disease?
can be both
- PRIMARY
~ dry eyes
~ dry mouth
~ dry vagina - SECONDARY (to other autoimmune diseases)
~ rheumatoid arthritis
~ PSS
~ SLE - patients may have over lying autoimmune disorders so it’s harder to distinguish/ may have mix of symptoms
SJOGREN’S SYNDROME
- what is it?
- F:M
- age
- symptoms
- increases risk of what
1
* Autoimmune sialadenitis
2
* F > M (9:1)
3
* 2 Peaks of onset
* mid 30s & postmenopausal 45-60
4
* Sicca symptoms (95%) - Dryness of mouth, eyes, skin, vagina
Dental carries; loss of teeth, candida
* Excessive fatigue (75%), arthralgia & myalgia
* Swollen salivary glands/lachrymal glands
5
* Increased risk of lymphoma/Maltoma
~ B cell lymphoma Mucosal Associated
Lymphoid Tissue
IMAGE 2
- tongue would be sticky if place mirror
- packed with candida - needs to be regularly treated
- lobulated fissured tongue