Gout and pseudogout Flashcards
How does gout typically present?
Acute monoarthropathy with severe joint inflammation
Which joint is most commonly affected in gout?
First metatarsophalangeal
Other common joints - ankle, foot, small joints of the hand, wrist, elbow, knee
What may precipitate acute attacks of gout?
Surgery Starvation Trauma Diuretics Infection
What is the pathophysiology of gout
Deposition of monosodium urate crystals in and near joints
Reduced urate excretion
Increased urate production
What are risk factors for decreased urate excretion?
Elderly, men, post menopausal females, impaired renal function, hypertension, metabolic syndrome, diuretics, antihypertensive, aspirin
What are risk factors for increased urate production?
Dietary - alcohol, sweeteners, red meat, seafood Genetic disorders Myelo/lymphoproliferative disorders Psoriasis Tumour lysis syndrome Drugs (alcohol, warfarin, cytotoxic)
What is associated with gout?
Cardiovascular disease
Hypertension
Chronic renal failure
Diabetes mellitus
What is gout an independent RF for?
Mortality from cardiovascular and renal disease
What should you screen for in gout?
CKD
HTN
DM
Dyslipidaemia
What investigations do you do for gout?
Polarized light microscopy of synovial fluid shows negatively birefringent urate crystals
Serum urate is usually raised but may be normal
Radiographs show only soft tissue swelling in early stages and more punched out erosions in late stages in juxta-articular bone
No sclerotic reaction and joint spaces are preserved until late
What is the treatment for acute gout and what is the treatment if this is CI
High dose NSAIDs
If CI - colchicine (500mcg BD - effective but slower to work) or steroids (PO,IM,IA)
Rest, elevation, ice, bed cages
How can gout be prevented non medically?
Lose weight, Avoid prolonged fasts, reduce alcohol, reduce purine rich meats and low dose aspirin
When is prophylaxis given for gout
After more than 1 attack in 12 months, if gouty tophi are present or if there are renal stones
Which main drug is given as gout prophylaxis?
Allopurinol - titrate from 100mg/24h, increasing every 4 weeks until plasma urate <0.3mmol/L (max 300mg/8hr)
What are the side effects of allopurinol?
May trigger an attack, rash, fever and decreased WCC
How long after an acute attack must you wait till prescribing allopurinol?
3 weeks
What must be given with allopurinol when starting?
NSAID for 6 weeks to prevent attack
Which drug is given as gout prophylaxis if allopurinol is CI?
Febuxostat (80mg/24h)
What should you do if a patient is on allopurinol and has an acute attack?
Keep them on it at the same dose- stopping and starting can cause more attacks
Give the main SE of febuxostat
Increases LFTs
Describe the presentation of pseudogout
Acute monoarthropathy usually of the larger joints in the elderly
What provokes an attack of pseudogout
Usually spontaneous but can be illness, trauma and surgery
Describe chronic CPPD
Inflammatory RA like (symmetrical) polyarthritis and synovitis
What are the risk factors for CPPD
Old age
Hyperparathyroidism
Hemochromatosis
Hypophosphatemia
What investigations do you do for pseudogout?
Polarized light microscopy on synovial fluid shows weakly positively birefringent crystals (rhomboid shaped)
Soft tissue deposition of calcium on Xray
What is the management for pseudogout?
Cool packs, rest, aspiration, intra-articular steroids
What can be given to prevent pseudogout attacks?
NSAIDs and colchicine (0.5-1mg/24h)
Which drugs can be considered in chronic CPP inflammatory conditions?
Methotrexate and hydroxychloroquine
What is the name of the underlying crystal in pseudogout?
Calcium pyrophosphate
What is a side effect of colchicine?
Diarrhoea
