Crystal Arthropathy Flashcards
What is a crystal deposition disease?
Deposition of mineralised material within joints and peri-articular tissue
If there is deposition of monosodium urate what disease is present?
Gout
If there is deposition of Calcium pyrophophate dihydrate what condition is present?
Pseudogout
If there is deposition of basic calcium phosphate hydroxy-apatite what condition is present?
Calcific periarthritis/ tendonitis
What is tophus
Massive accumulation of uric acid
2 classes of causes of hyperuricaemia?
Overproduction of uric acid or under excretion
Causes of overproduction of uric acid?
Malignancy eg lymhoproliferative, tumour lysis syndrome, Severe exfoliative psoriasis, Drugs eg ethanol, cytotoxic drugs, Inborn errors of metabolism, HGPRT deficiency
Causes of under excretion causing hyperuricaemia?
Renal impairment, Hypertension, Hypothyroidism, Drugs eg alcohol, low dose aspirin, diuretics, cyclosporin, Exercise, starvation, dehydration, Lead poisoning
What causes Lesch Nyan Syndrome?
HGPRT deficiency,
Is X-linked recessive
What are the symptoms of Lesch Nyan Syndrome?
Intellectual disability, Aggressive and impulsive behaviour, Self mutilation, Gout, Renal disease
Management of an acute flare of gout?
NSAIDs,
Colchicine,
Steroids
Does the 1st attack of hyperuricaemia need to be treated?
No, unless.... Is a single attack of polyarticular gout, Tophaceous gout, Urate calculi, Renal insufficiency
How do you lower uric acid?
Xanthine oxidase inhibitor eg Allopurinol,
Febuxostat,
Uricosuric agents eg sulphinpyrazone, probenecid, benzbromarone,
Canakinumab
What are the rules of lowering uric acid levels?
Need to wait until an acute episode has settled,
Use prophylactic NSAIDs or low dose colchicine/steroids until urate levels are normal,
Need to adjust allopurinol dose according to renal function
What is pseudogout?
Gout of the knee most commonly in elderly females and has erratic flares
Aetiology of pseudogout
Idiopathic, familial, metabolic
Triggers of pseudogout?
Trauma, intercurrent illness
Management of pseudogout
NSAIDs, steroids
Polymyalgia rheumatica presentation
Sudden onset of shoulder +/- pelvic girdle stiffness in >50year old paitient, Anaemia, Malaise, Weight loss, Fever, Depression, Arthralgia/ synovitis
Investigations for polymyalgia rheumatica?
ESR (>50),
Steroid response
Differential diagnosis of polymyalgia rheumatica
Myalgic onset inflammatory joint disease, Underlying malignancy, Inflammatory muscle disease, Hypo/ hyperthyroidism, Bilateral shoulder capsulitis, Fibromyalgia
Treatment of polymyalgia rheumatica?
Prednisone 15mg per day (18-24 month course),
Bone prophylaxis
