Crystal Arthropathy: Gout Flashcards
What is crystal arthropathy?
A class of joint disorders characterised by the deposition of crystals in joint spaces, leading to inflammation and damage.
What are the two most common forms of crystal arthropathy?
- Gout
- Pseudogout (CPPD crystal deposition disease)
What causes gout?
Monosodium urate crystals due to chronically high blood uric acid levels.
What is a typical presentation of gout?
A single acute hot, swollen, and painful joint.
What is the critical differential diagnosis for gout?
Septic arthritis.
Where are gouty tophi commonly found?
- Hands
- Elbows
- Ears
List some risk factors for gout.
- Male
- Family history
- Obesity
- High purine diet (e.g., meat and seafood)
- Alcohol
- Diuretics
- Cardiovascular disease
- Kidney disease
Which joints are typically affected by gout?
- Base of the big toe (MTP joint)
- Base of the thumb (CMC joint)
- Wrist
Can gout affect larger joints?
Yes, it can also affect larger joints like the knee and ankle.
How is gout diagnosed?
Clinically, supported by a raised serum urate level on a blood test.
What must be excluded when diagnosing gout?
Septic arthritis.
What does aspirated joint fluid show in gout?
Monosodium urate crystals that are needle-shaped and negatively birefringent under polarized light.
What are the X-ray findings in a joint affected by gout?
- Maintained joint space
- Lytic lesions in the bone
- Punched out erosions
- Erosions with sclerotic borders and overhanging edges
What is the first-line treatment for acute gout flares?
NSAIDs (e.g., naproxen) co-prescribed with a proton pump inhibitor.
What is the second-line treatment for acute gout flares?
Colchicine.
