GOUT Flashcards
What is gout?
Deposition of monosodium urate crystals into the joint space.
What is pseudogout?
Calcium pyrophosphate (CPP) crystals deposit within the joints and can cause acute CPP crystal arthritis (also known as pseudogout)
Where does it often affect?
The big toe
Where is the worst pain point?
6-14hrs
How long do symptoms last?
3-10 days
What is the onset like?
Relapse of attacks
What is caused by?
build up of uric acid in blood
What is uric acid?
Uric acid is a waste product made in body everyday and excreted in the kidneys. If produce too much uric acid or excrete too little in the urine, causes tiny crystals of sodium urate to form in and around joints
What can it lead to?
kidney stones, tophus formation (lumps under skin) and permanent joint damage
What is the prevalence?
1%
More common in men and women?
W:M, 5:1
What is the aetiology?
- Presents as an acute monoathropoathy with severe joint inflammation
- Caused by deposition of monosodium urate crystals in and near joints
- Ppt by trauma, surgery, starvation, infection, diuretics
- Assoc. w/raised plasma urate
What are the risk factors?
- Obesity
- High protein diet
- High alcohol consumption (esp. beer)
- High fructose intake from fizzy drinks
- Combined hyperlipidaemia
- DM
- Ischemic heart disease and HTN ( metabolic syndrome)
- FH
- Leukaemia
- Cytotoxics – tumour lysis
- Impaired excretion uric acid
- Chronic renal disease/renal impairment
- Drug therapy – Thiazides, low dose aspirin
- Incr production uric acid
- Hypothyroidism
- Primary hyperparathyroidism
What are the key symptoms? (3)
- Sudden onset agonising pain, swelling and redness in first MTP joint
- Reaches crescendo over a 6-12 hr period with peak at 24 hours
- Fever and malaise
Which joint is most affected?
1st MTP
What are the signs?
- Florid synovitis and swelling w/extreme tenderness and overlying erythema
- Resolves spont 5-15d with itching and desquamation overlying skin
- Appearance of TOPHI – asymmetrical w/chalky appearance beneath the skin = urate deposits in pinna, tendons and joints
- Have restricted movement, Crepitus and deformity
- L/T – renal disease (stones, interstitial nephritis)
What characteristic symptoms?
o Difficult walking or inability to use joints
o Touch or pressure
o Overlying erythema
What is characteristic time-course?
Time to maximal pain <24 hours. Resolution of symptoms in ≤14 days
What is the common pattern of joint involvement?
o Joint(s) or bursa(e) other than ankle, midfoot or first metatarsophalangeal (MTP) joint (or their involvement only as part of a polyarticular presentation). o Ankle or midfoot joint(s) as monoarticular or part of an oligoarticular presentation without first MTP joint involvement. o MTP joint involvement as monoarticular or part of an oligoarticular presentation.
What clinical evidence of typhus are you looking for?
o Appearance: draining or chalk-like subcutaneous nodule under transparent skin, often with overlying vascularity.
o Classic locations: joints, ears, olecranon bursae, finger pads, tendons (eg, Achilles).
What evidence imaging?
Imaging evidence of gout-related joint damage and urate deposition
What investigations?
- Polarised light microscopy of synovial fluid – shows –ve bifringement urate crystals
- Serum urate – raised but may be normal
- Radiographs – soft tissue swelling initially. Later see well-defined ‘punched out’ erosions in juxta-articular bone. There is no sclerotic reaction and joint spaces preserved until late.
- Joint fluid microscopy
- Serum urea and creatinine
What are the treatments? (and what drug class are they?)
• Strong NSAID eg diclofenac 50mg/8hr PO
• Colchisine – 0.5mg/6hr PO
• Caniknukimab - IL-inhibitor
Steroids
When can’t you use NSAID’s and Colchisine?
those with renal impairment
