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.
What is the third-line treatment for acute gout flares?
Oral steroids (e.g., prednisolone).
In which patients is colchicine used?
Patients who are inappropriate for NSAIDs, such as those with renal impairment or significant heart disease.
What are common side effects of colchicine?
Abdominal symptoms and diarrhea.
What is the maximum dose of colchicine for a short course?
Up to 6mg per course.
What is used for prophylaxis in gout management?
Xanthine oxidase inhibitors to lower uric acid levels.
Name two xanthine oxidase inhibitors.
- Allopurinol
- Febuxostat
What lifestyle changes can reduce the risk of gout?
- Losing weight
- Staying hydrated
- Minimising alcohol and purine-based food consumption (e.g., meat and seafood)
When is prophylaxis for gout started?
Not until weeks after the acute attack has resolved.
What may be given to prevent a gout attack during the initial period of treatment?
NSAIDs or colchicine.
Should allopurinol or febuxostat be continued during an acute attack?
Yes, they should be continued.
