Osteoarthritis and Reactive Arthritis Flashcards
Define reactive arthritis.
Sterile inflammation in joints following infection, especially urogenital and gastrointestinal infections
State a urogenital infection that can cause reactive arthritis.
Chlamydia trachomatis
Give some examples of gastrointestinal infections that are associated with reactive arthritis.
Shigella Salmonella Campylobacter
What subset of the population does reactive arthritis tend to occur in?
It occurs mainly in young adults with a genetic predisposition and an environmental trigger
How long after the infection does the reactive arthritis tend toappear?
1-4 weeks
Describe the features of the arthritis in reactive arthritis.
It is an asymmetrical arthritis that occurs in relatively few joints
Reactive arthritis can cause enthesopathy. Which entheses are likely to get affected and what symptoms will that cause?
Achilles tendonitis Dactylitis Metatarsalgia (painful feet because of inflammation of the palmar fascia)
What is a very common feature of seronegative spondyloarthropathies?
Sacro-iliitis
State some extra-articular features of reactive arthritis?
Sterile conjunctivitis Sterile urethritis Circinate balanitis Keratoderma blennorhagicum
What is the triad of symptoms that can be used to describereactive arthritis?
Reiter’s syndrome – joint inflammation + urethritis + conjunctivitis
Where can you get spondylitis in rheumatoid arthritis?
At the atlanto-axial joint – there is synovium her
Describe the main differences between rheumatoid arthritis and reactive arthritis.
Rheumatoid Arthritis vs Reactive Arthritis Sex Ratio: F>M - M>F Arthritis: Symmetrical, Polyarticular, Small&Large Joints - Asymmetrical, Oligoarticular, Large joints Enthesopathy: NO - YES Spondylitis: NO (Except atlanto-axial joint in cervical spine) - YES Urethritis: NO - YES Skin involvement: Subcutaneous nodules - K.blennorhagicum, Circinate balanitis Rheumatoid factor: YES - NO HLA association: HLA-DR4 - HLA-B27
What is the main danger in septic arthritis?
The bacteria produce metalloproteinases that can rapidly degrade thearticular cartilage
What are the main differences between septic arthritis and reactive arthritis?
Septic arthritis has a positive synovial fluid culture It is treated with antibiotics and may even require joint lavage
Describe the treatment of reactive arthritis.
It usually resolves by itself NSAIDs to control pain and symptomatic treatment of extra-articular manifestations
Define osteoarthritis.
Chronic slowly progressive disorder due to failure of articular cartilage that typically affects the hands (especially those involved in the pinch grip), spine and weight-bearing joints (hips and knees)
Which joints are most commonly affected in osteoarthritis?
DIP PIP First metacarpophalangeal joint Spine Knees Hips First metatarsophalangeal joint
What are the names given to the osteophytes found on the hand in osteoarthritis?
Bouchard’s Nodes – PIP Heberden’s Nodes – DIP
What are some other associations of osteoarthritis?
Joint pain (worse with activity) Joint crepitus Joint instability Joint enlargement Joint stiffness after immobility Limitation of motion
What are some radiographic features of osteoarthritis?
Joint space narrowing Osteophytes Subchondral bony sclerosis Subchondral cysts
Describe the differences between the radiographic features of rheumatoid arthritis and osteoarthritis.
Rheumatoid arthritis also has joint space narrowing but it doesn’t have subchondral sclerosis or osteophytes There is osteopenia and there are bone erosions in rheumatoid arthritis but not in osteoarthritis
What can the osteoarthritis be caused by?
Abnormal cartilage Abnormal stress
What is the most important component of articular cartilage?
Aggrecan
What is aggrecan made up of?
Chondroitin sulphate – glucuronic acid + N-acetyl galactosamine Keratan sulphate – galactose + N-acetyl glucosamine
What is a proteoglycan?
Glycoproteins that contain one or more sulphated glycosaminoglycan (GAG) chains
What is special about hyaluronic acid?
It is the only non-sulphated GAG
What are the disaccharides in hyaluronic acid?
Glucuronic acid N-acetyl glucosamine
How is osteoarthritis managed?
Physiotherapy – strengthening the muscle around the joint improves joint stability Analgesia – paracetamol, NSAIDs, intra-articular corticosteroid injections Joint replacement Weight loss where appropriate
