Osteoarthritis and reactive arthritis Flashcards
In what cateory of disease is reactive arthritis
Seronegative sponyloarthropathies
What is reactive arthritis
sterile inflammation in joints following infection especially urogenital and gastrointestinal infectin
State the bacteria causing the urogenital and GI infections that may lead to reactive arthritis
Urogenital
e.g. Chlamydia trachomatis
and gastrointestinal (e.g. Salmonella, Shigella, Campylobacter infections)
NOT DUE TO CHRONIC INFECTIN
What important extra-articular manifestations
Enthesopathy (like ankylosing sponylitis, both part of same disease category)
Skin inflammation
Eye inflammation
Reactive arthritis may be first manifestations of which viral infections
of HIV or hepatitis C infection
What is the environmental trigger and genetic component of reactive arthritis
Commonly young adults with genetic predisposition (e.g. HLA-B27) and environmental trigger (e.g. Salmonella infection)
When do symptoms of reactive arthritis occur
1-4 weeks after infection and this infection may be mild
Differentiate septic arthritis and reactive arthritis
Reactive arthritis is distinct from infection in joints (septic arthritis)… reactive arthritis is sterile inflammation
Synovial fluid culture positive in SA, neg in reactive
YES antibiotics in septic arthritis, NO antibiotics in reactive
YES joint lavage for large joint in septic arthritis, NO for reactive
Outline the musculoskeleal symptoms of reactive arthri.
Arthritis: Asymmetrical Oligoarthritis (<5 joints) Lower limbs typically affected
Enthesitis (inflammation where ligaments/tendons meet bone) \: Heel pain (Achilles tendonitis) Swollen fingers (dactylitis) Painful feet (metatarsalgia due to plantar fasciitis)
Spondylitis:
Sacroiliitis (inflammation of the sacro-iliac joints)
Spondylitis (inflammation of the spine)
What are the extra articular features of reactive arthritis
Ocular- Sterile conjunctivitis
Genuitourinary- Sterile urethritis
Skin- Circinate balaniti (i.e annular dermatitis of the glans penis), Psoriasis-like rash on hands and feet ‘
Differentiate rheumatoid and reactive arthritis
Rheumatoid symmetrical, reactive asymmetrical.
In rheumatoid, no thoracic and lumbar involvement (not synovial joints). Reactive arthritis, just like in ankylosing spondylitis, can involve this
HLA association is HLA-DR4 in rheumatoid, and HLA-B27 in reactive arthritis
Urethritis, spondylitis and enthesopathy all presnet in reactive arthritis but not rheumatoid
How is reactive arthritis diagnosed
Clinical diagnosis
Investigations to exclude other causes of arthritis e.g. septic arthritis
investigations
Outline the investigations of reactive arthritis
Microbiology
Microbial cultures – blood, throat, urine, stool, urethral, cervical
Serology e.g. HIV, hepatitis C
Immunology
- Rheumatoid factor should be neg
- HLA-B27 present (although this ispresent in 9% anyway)
Synovial fluid examination
-Especially if only single joint affected
How is reactive arthritis treated
NO ROLE FOR ABs
Symptom management:
artcualr: NSAIDs/intr-articular corticosteroid therapy
extra-articular: typically self limiting so symptomatic therapy (topical steroids/keratolytic agents in keratoderma)
refractory disease:
- oral glucocorticoids
- steroid-sparing agents e.g. sulphasalazine
What is osteoarthritis
Chronic slowly progressive disorder due to failure of ARTICULAR CARTILAGE that typically affecting joints of the hand (especially those involved in pinch grip), spine and weight-bearing joints (hips and knees)
ARTICULAR CARTILAGE PROBLEM, NOT THE SYNOVIUM
What would be seen in x ray
Bones closer together (not separated by cartilage)
Which joints are commonly affected by osteoarthritis
affects
Joints of the hand:
-Distal interphalangeal joints (DIP)
- Proximal interphalangeal joints (PIP)
- First carpometacarpal joint (CMC)
Spine
Weight-bearing joints of lower limbs
- esp. knees and hips
- First metatarsophalangeal joint (MTP)
Clinical features of osteoarthritis
Pathomnemonic of osteoarthritis
Osteophytes at the DIP joints are termed Heberden’s nodes
Osteophytes at the PIP joints are termed Bouchard’s nodes
Differentiate activity levels with osteoarthritis and rehumatoid arthritis
OSTEO gets worse with movement
With rhematoid patients can feel it’s better as you get going
What are the features of osteoarthritis
Joint pain
worse with activity, better with rest
Joint crepitus
creaking, cracking grinding sound on moving affected joint
Joint instability
Joint enlargement
e.g. Heberden’s nodes
Joint stiffness after immobility (‘gelling’)
Limitation of motion
What are the radiographic features of osteoarthritis
Joint space narrowing
Subchondral bony sclerosis
Osteophytes
Subchondral cysts
Differentient radiographic features in osteoarthritis and rheumatoid arthritis
Joint space narrowing in both
Subchondral sclerosis in OA not RA
Erosions seen in rhematoid arthrisis not osteo
Osteophytes seen inn osteo and not rheumatoid
Osteopenia in RA not OA
*Joint space narrowing indicates articular cartilage loss
What happens to articular cartilage in osteoarthritis and why
There is defective and irreversible articular cartilage and damage to underlying bone
Excessive loading on joints
and/or
Abnormal joint
components
What would the osteoarthritis usually be to do with in youner and older patients
In younger, probabbly abnormal cartilage
In older abnormal stress
Outline the composition of the articular cartiage
Collage (>90% is type II)
Chondrocytes
Proteoglycan monomers (aggrecan)0 EXPAND
Outline ECM proeoglycans….
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Outline the changes in osteoarthritis
Cartilage changes in osteoarthritis:
- reduced proteoglycan
- reduced collagen
- chondrocyte changes e.g. apoptosis
Bone changes in osteoarthritis:
- Changes in denuded sub-articular bone
- Proliferation of superficial osteoblasts results in production of sclerotic bone e.g. subchondral sclerosis
- Focal stress on sclerotic bone can result in focal superficial necrosis
new bone formation at the joint margins (termed osteophytes ie. the nodes at the DIP and PIP)
State the management of osteoarthritis
Education
Physical therapy – physiotherapy, hydrotherapy
Occupational therapy
Weight loss where appropriate
Exercise
Analgesia
- Paracetamol
- Non-steroidal anti-inflammatory agents
- Intra-articular corticosteroid injection
Joint replacement
T/f Like rheumatoid, there is a disease modifying osteoarthriris drug
F…..
