Gout Flashcards
Pathophysiology
Deposition of monosodium urate crystals in and around joints → erosive arthritis
May be precipitated by surgery, infection, fasting or diuretics
Common joints
Big toe MTP 60%
Ankle, foot, hand joints, wrist, elbow, knee
Presentation
- M>F=5:1
- Acute monoarthritis with severe joint inflammation
- Asymmetric oligoarthritis
Tophi
Urate deposits in pinna and tendons
Associated conditions
Renal disease: radiolucent stones and interstitial
nephritis
HTN
IHD
Metabolic syndrome
Causes of gout
Hereditary
Drugs: diuretics, NSAIDs,
↓ excretion: renal impairment
↑ cell turnover: lymphoma, leukaemia, psoriasis,
haemolysis
EtOH excess
Purine rich foods: beef, pork, lamb, seafood
Ix of gout
Joint examination Basic obs Bloods: FBC, Urate (may be normal) Polarised light microscopy - Negatively birefringent needle-shaped crystals
X-ray changes
Signs occur late
- Punched-out erosions in juxta-articular bone
- ↓ joint space
Mx
NSAID: diclofenac or
Colchicine
In renal impairment: NSAIDs and colchicine are CI
→ Use steroids
Preventions
Conservative:
- Lose wt.
- Avoid prolonged fasts and EtOH excess
Xanthine Oxidase Inhibitors: Allopurinol
- Use if recurrent attacks, tophi or renal stones
- Introduce with NSAID or colchicine cover for 3/12
Uricosuric drugs: e.g. losartan
(Rarely used)
Allopurinol allergy
Use febuxostat (XO inhibitor)
Pseudogout
Arthritis that results from deposits of calcium pyrophosphate crystals
Presentation of pseudogout
Causes pain, stiffness, tenderness, redness, warmth and swelling (inflammation) in normally one joint
Usually knee, hip or wrist
RF for pseudogout
↑ age OA DM Hypothyroidism Hyperparathyroidism Hereditary haemochromatosis Wilson’s disease
Gout Polarised light microscopy results
Negatively birefringent needle-shaped crystals
