Crystal Arthropathies Flashcards
Name the 2 types of crystal arthropathies?
Gout
Pseudogout
What is meant by ‘crystal arthropathies’?
Deposition of crystals in joints causing arthritis
What is Gout?
Deposition of monosodium urate crystal in and near joints
Which joints are particularly affected by Gout?
The metatarsophalangeal joint of the big toe
Hand and foot joints are most often affected
But any joint can be
Which crystal is involved in Gout?
Monosodium urate
What conditions does Gout increase the risk of?
Cardiovascular disease:
- stroke
- MI
Renal disease
Diabetes
How is uric acid processed by the body?
It is carried around the body in the bloodstream
You get rid if it via the kidneys
What is the difference between urate and uric acid?
Urate is the salt of uric acid
What causes a rise in urate in the body?
Genetic conditions that affect the absorption of urate
Increased intake in diet
Increased cell turnover: like in psoriasis
Cell damage or death: surgery/chemo
Kidney problems that mean they can’t get rid of urate properly
Drugs
Why do crystals form?
When concentration of urate gets too high in the blood crystals begin to form
As with any concentrated substance
When treating gout you want to reduce uric acid levels in the blood. To what level are you aiming for?
About 300, low enough that crystals don’t form
Clinical features?
A chronic disease, but now and then attacks occur
Attacks:
A hot, red, inflamed joint
Often starts overnight and wakes them up
It is intense pain, can’t even stand bedsheets touching the joint
Causes of gout?
Diet: an excess of:
- alcohol
- red meat
- seafood
- fructose, sugary food/drinks
Renal problems:
- unable to filter urate out
Hereditary:
- psoriasis, increased cell proliferation
Cherries are protective in gout. What else is?
Dairy
Other sources of vitamin C
Investigation of gout?
Aspirate and collect crystals to analyse
Blood:
- serum urate levels raised
X-rays:
- show soft tissue swelling early on, bone deformity later
