Gout and pseudogout Flashcards
What is gout?
Gout is a form of inflammatory arthritis characterised by recurrent attacks of a red, tender, hot, and swollen joint.
What joint is most affected in gout?
The metatarsal-phalangeal joint at the base of the big toe is affected most often, accounting for half of cases
Other joints, such as the heels, knees, wrists, and fingers, may also be affected
What are the signs and symptoms of gout?
Pain, red, tender, hot, swollen
Joint pain usually begins during the night and peaks within 24 hours of onset
What causes gout?
The crystallization of uric acid, often related to relatively high levels in the blood, is the underlying cause of gout
Crystals may break off tophi and trigger a local immune-mediated inflammatory reaction in macrophages, which is initiated by the NLRP3 inflammasome protein complex, and an inflammatory cascade follows
What are the risk factors for gout?
Gout occurs more commonly in those who regularly drink beer or sugar-sweetened beverages or who eat foods that are high in purines such as liver, shellfish, or anchovies, or are overweight
How would you manage an attack of gout?
NSAIDs, glucocorticoids
How would you prevent secondary gout?
Lowering uric acid levels with lifestyle changes and medication
What medication can reduce the levels of uric acid (and thus reduce gout)?
Allopurinol or probenecid
What is a tophus?
A tophus is a deposit of monosodium urate crystals, in people with longstanding high levels of uric acid in the blood
They are often walled off by a ring of proteins, blocking interaction with cells and avoiding inflammation
How can uric acid crystals break off from a main trophus?
Minor physical damage to the joint, medical or surgical stress, or rapid changes in uric acid levels
How is gout diagnosed?
Gout may be diagnosed and treated without further investigations in someone with hyperuricemia and the classic acute arthritis of the base of the great toe
Synovial fluid analysis should be done if the diagnosis is in doubt
What is pseudogout?
A rheumatological disease which is thought to be secondary to abnormal accumulation of calcium pyrophosphate dihydrate crystals within joint soft tissues
What is the deposition seen in pseudogout?
Calcium pyrophosphate dihydrate crystal deposition
What are the signs and symptoms of pseudogout?
When symptomatic, the disease classically begins with symptoms that are similar to a gout attack:
- Warmth
- Severe pain
- Swelling
How would you diagnose pseudogout?
The disease is defined by presence of joint inflammation and the presence of CPPD crystals within the joint. The crystals are usually detected by imaging and/or joint fluid analysis
