Hot Swollen Joint Flashcards
What is the differential diagnosis for red swollen knee?
Septic arthritis Gout Flare up of OA Pseudogout RA Reactive arthritis MSK injury Haemarthosis Psoriatic arthritis Lyme disease
What investigations would you do for someone with red swollen knee?
Baseline blood + CRP/ESR
Joint space Aspiration
X-Ray - fracture?
What are some signs to look for on examination painful swollen joint?
Erythema Swelling Temp Joint line tenderness Scars Range of movement
What test would you request from the aspiration?
Gram stain
Leukocytes count
Polarising microscopies (crystals)
MC&S (microscopy, culture and sensitivity)
Describe the fluid that may be seen in aspiration of septic arthritis?
Turbid
What is the most common microorganisms that cause septic arthritis?
Staphylococcus aureus
Neisseria gonorrhoea (in younger pts)
What are the three ways bacteria will ‘seed’ into joint?
Bacteraemia (e.g. UTI , cellulitis, chest infection)
Direct inoculation
Spreading from adjunct osteomyelitis
What are the risk factors for septic arthritis?
Age >80 Pre-existing joint disease DM/immunosuppressive CKD Prosthesis IV drug use
Why is surgical history important in painful swollen joint?
Due to prosthetic joint infections which need to be aspirated in theatre
What other imaging will be useful for suspected septic arthritis?
CT or MRI if in sternoclavicular/sacroiliac
Radionuclide scans - isolated joints in sacroiliac joint
What is the management for septic arthritis?
Joint washout/irrigation (open/arthroscopic)+ debridement
Samples taken
Empirical Antibiotics started
Monitoring post-op
How long are antibiotics given in septic arthritis?
Two weeks IV
The oral after that up to 6 weeks
What is the main complications of septic arthritis?
OA
Osteomyelitis
Does a negative gram stain rule out septic arthritis?
No, only 30% have positive gram stain
What are the management options for prosthetic joint infections (PJI)?
- Non-operative - long -term antibiotics - elderly, un-fit for surgery
- DAIR procedure - joint washout + replace plastic part of implant
- one/two-stage revision procedure
- excision arthroplasty + may have arthrodesis
- Amputation
What is the GOLD standard treatment for prosthetic joint infections?
Two-stage revision procedure
What are the associated feature of reactive arthritis?
Anterior uveitis
Conjunctivitis
Urethritis
Which gene is associated with reactive arthritis?
HLA-B27
What is the risk factors for atraumatic haemarthosis?
Clotting disorder
Anticoagulants
What is the treatment for atraumatic haemarthosis?
RICE , Splinting, analgesia
Manage clotting disorder
Aspiration may provide relief but may recur
What is the most common joint affected by pseudogout?
Knee
Followed by wrist
What can be seen on an X-ray of pseudogout?
Chondrocalinosis
What is seen on polarising microscopy for pseudogout?
Positivity bifingement rhomboid-shaped crystals
What is the treatment for pseudogout?
RICE, Splinting, analgesia
NSAIDS if tolerated
Intra-articular steroids
Colchicine can be used prophylactially
Which joint does gout usually affect?
1st MTP joint
What is seen on polarising microscopy in gout?
Needle shaped mondo sodium urate crystals, negatively bifringement
What may be seen on a x-ray of gout?
Subcondral sclerosis, swelling, erosions
Punched out lesions
What are the two types of gout?
Primary - idiopathic - purine metabolism
Secondary - associated with disease with high metabolic turnover e.g. psoriasis, chemo
Is serum urate diagnostic of gout?
No it is not useful in acute phase but may be used to monitor treatment e.g from allopurinol
What is the treatment of gout?
NSAIDs or colchicine in acute phase (consider glucosteroids)
Long term in recurrent attacks - Allopurinol or colchicine - 6 weeks after acute attack
What are the risk factors for pseudogout?
Hyperparathyroidism
Hypophosphatemia
Advanced age
What is the classification used for RA?
EULAR classification
What conditions are in the group of spondyloarthopathies?
Psoriatic arthritis
Ankylosing spondylitis
Reactive arthritis
Enteropathic arthropathy
Seronegative conditions - associated with HLA B27
