MSK 6 Inflammatory Arthropathies Flashcards
Inflammatory arthropathies:
Common Types →
➢ Rheumatoid Arthritis (RA) ➢ Spondyloarthropathies ➢ Systemic lupus erthematosus (SLE) ➢ Crystal-related arthropathies ➢ Polymyalgia rheumatic
Rheumatoid Arthritis:Cause
T cell driven (autoimmune) disease
Rheumatoid Arthritis: Early signs
Joint stiffness (15 mins lasting)
Joint tenderness
Cant close fist
Loss of grip strength
Rheumatoid Arthritis:Longer signs
Multiple joints involved
Evidence of deformities in joints
Poor skin/ulceration
Severe limitation of movement
Rheumatoid Arthritis:Pathogenesis
Mass of tissue forms → Pannaus containing macrophage setc. (pro-inflammatory cells)
Mass of tissue (Pannaus) secrete enzymes that erodes cartilage and bone
Rheumatoid Arthritis:Serum
Seropositive
Spondyloarthropathies: General definition
Group of rheumatic diseases regarded as a variant of RA but distinct from it
Spondyloarthropathies:Main features
- A family of inflammatory joint diseases characterised by involvement of synovium and enthuse (tendon insertion sites)
- Leads to spinal and oligarticular peripheral arthritis in genetically predisposed (HLA B27) individuals
- Spine effected (high frequency)
- Multiple joints effects
- Bowel inflammation
- Eye inflammation
- Cytotoxic T cell inflammation (initiation) recognising antigen bound to HLA B27)
Spondyloarthropathies: Common types of spondylarthropathies
- Ankolysing spondylitis
- Reactive arthritis
- Psoriatic arthrisis
Spondyloarthropathies: Key features
Enteses →tendon insertion sites.
Ankolysing spondylitis: Definition
Ankolysing (fusion) spondylitls (arthritis of vertebrae) is a chronic inflammatory rheumatic disease that primarily affects the sacroiliac joints and spine.
Ankolysing spondylitis: Characteristic features
Severe back pain
Early morning stiffness of effected joints
Dorsal pysphosis
Flatten lumbar lorodis
Flattened knee
Prominent abdominal folds
Severe limitation in movement in all planes
Ankolysing spondylitis: Common joints effect
Spine
Shoulder
Hip joint
Sacroliliac joints
Ankolysing spondylitis: Tendon insertion sites eroded
Pelvis ASIS etc.
Ankolysing spondylitis: Serology
Most markers of systemic markers elevated (CRP) (ESR).
Ankolysing spondylitis: Gross anatomy of spine
Formation of bony bridges uniting vertebraes
Ankolysing spondylitis: Epi
The male to female ratio: 5:1
Ankolysing spondylitis: Defining feature
Involves high frequency of inflammation at the enthese
Ankolysing spondylitis: 90% of the patients
Are HLA B27 positive compared to 6% of the unaffected individuals. Unique structure of HLA B27 suggest that CD8+ T-cells or natural killer cells are involved in pathogenesis
Ankolysing spondylitis: Serum
Seronegative – no rheumatoid factors in the blood
Ankolysing spondylitis: Prevalence
0.5-1.0% in Caucasians
Ankolysing spondylitis: Mechanism of AS
HLA-B27 carry specific amino acids can bing to appropriate antigen that triggers AS
Reactive arthritis: (Rieter’s syndrome) Definition
Initial arthritis can be described as antibodies and T-lymphocytes reacting with the bacterial antigens
Reactive arthritis: (Rieter’s syndrome)Confirmation
Test synovial fluid and stain for bacteria associated with reactive arthritis
Reactive arthritis: (Rieter’s syndrome)Treatment
Antibiotics?
Reactive arthritis: (Rieter’s syndrome)Joint inflammation
Occurs in 1-4% of the patients following enteric infection with: 1. Salmonella 2. Shigella 3. Camplyolbacter Yersinia
Reactive arthritis: (Rieter’s syndrome) Pathogenesis
Bacterial component and T-cell eactive to these antigens can be found within the synovial membrane and synovial fluid
Reactive arthritis: (Rieter’s syndrome) Epi
Male: female equal
Reactive arthritis: (Rieter’s syndrome) Features
Skin lesions (keratoderma blenorrhagicum/pustulosis palmoplantaris)
Reactive arthritis: (Rieter’s syndrome) 60-70% of patients
Are positive for HLA B27
Psoriatic arthritis: Definition
Is an inflammatory skin disorder characterised by epidermal hyper-proliferation and abnormal keratinisation (skin)
Psoriatic arthritis: Features
Typically effects small joints of hand
But Can also effect elbow and knee
Mirrored image
Psoriatic arthritis:Joint involvement
Wrist
Phalanges
Shoulder
Metatarsals
Psoriatic arthritis: Koebner phenononmen
Factors trigger (heat, tropical medicine, clothes) psoriasis to flare
Psoriatic arthritis:Immune involvement
Eviden of involvement and production od pro-inflammatory cytokines (Il-1, TNF)
Psoriatic arthritis:Epi
5-8% develop arthritis and the prevalence in Caucasians is between 0.2 and 0.1%
Psoriatic arthritis:Treatment and explanation
Though to be a TH1 mediated disease because of the beneficial effects of cyclosporine (immunesuppressant) A and other anti-CD4 treatmetns
Psoriatic arthritis:Antigen involved
Unknown but antigens derived from the keratinocytes or group A streptococci are possible candidates.
Systemic Lupus erythematousus: Definition
An inflammatory multi-system disease associated with complement C4 deficiency
Systemic Lupus erythematousus:Clinical features
Inflamamtion in various organ systems including skin and mucus membrane, joints, kidneys, brain,serous membranes, lung, heart, GI tract.
Systemic Lupus erythematousus: Affect
Primarily women
Systemic Lupus erythematousus: Common manifestation
- Arthritis but not erosive or destructive of bone
- Butterfly redness – from sunlight
- Any part of body exposed to sunlight
- Vasculitis
→ Small vessels effected = Necrosis around nails and skin of fingertips - Acute arthritis may affect any joint but the small joints of the hands, wrist and knees are involved
- Soft tissue swelling and joint effusions present
Systemic Lupus erythematousus: Pathological processes in SLE
- Inherited complement deficiencies
- Histocompatibility antigens – freqeuncy of HLA-A1, B* and DR3 is 3x greater in SLE than controls
- Sex hormones – SLE is 6-10x higher in females
- Polyclonal B-cell activation and multiple autoantibody production
Systemic Lupus erythematousus: Recognisable feature
- Most cases are symmetric but asymmetric polyarthritis is also seen
Crystal-related arthropathies: Epi
More common in men
40-60yrs
Crystal-related arthropathies: Characterised
Acute attacks of arthritis
Crystal-related arthropathies:Pathology
Urate crystals in synovial fluid from patients with gout
Crystal-related arthropathies:Two types
Gout → Urate crystals
Pseudo Gout → different crystals calcium pyrophosphate dehydrate (CPD)
Crystal-related arthropathies: Two genes associated with Gout
ABCG2
SLC2A9
Crystal-related arthropathies: Long-term mechanisms and presentation
Tophi – accumulations of crystals
Crystals become coated with proteins in synovial fluid e.g. MSU crystal can become coated with IgU
Apolipoprotein coats the crystals and inhibits the recognition by pro-inflammatory cells