Crystal Arthropathy

Question 1

What is a crystal deposition disease?

Answer 1

Deposition of mineralised material within joints and peri-articular tissue

Question 2

If there is deposition of monosodium urate what disease is present?

Answer 2

Gout

Question 3

If there is deposition of Calcium pyrophophate dihydrate what condition is present?

Answer 3

Pseudogout

Question 4

If there is deposition of basic calcium phosphate hydroxy-apatite what condition is present?

Answer 4

Calcific periarthritis/ tendonitis

Question 5

What is tophus

Answer 5

Massive accumulation of uric acid

Question 6

2 classes of causes of hyperuricaemia?

Answer 6

Overproduction of uric acid or under excretion

Question 7

Causes of overproduction of uric acid?

Answer 7

Malignancy eg lymhoproliferative, tumour lysis syndrome, 
Severe exfoliative psoriasis,
Drugs eg ethanol, cytotoxic drugs,
Inborn errors of metabolism, 
HGPRT deficiency

Question 8

Causes of under excretion causing hyperuricaemia?

Answer 8

Renal impairment, 
Hypertension, 
Hypothyroidism, 
Drugs eg alcohol, low dose aspirin, diuretics, cyclosporin,
Exercise, 
starvation, 
dehydration, 
Lead poisoning

Question 9

What causes Lesch Nyan Syndrome?

Answer 9

HGPRT deficiency,

Is X-linked recessive

Question 10

What are the symptoms of Lesch Nyan Syndrome?

Answer 10

Intellectual disability, 
Aggressive and impulsive behaviour,
Self mutilation,
Gout,
Renal disease

Question 11

Management of an acute flare of gout?

Answer 11

NSAIDs,
Colchicine,
Steroids

Question 12

Does the 1st attack of hyperuricaemia need to be treated?

Answer 12

No, unless....
Is a single attack of polyarticular gout, 
Tophaceous gout, 
Urate calculi, 
Renal insufficiency

Question 13

How do you lower uric acid?

Answer 13

Xanthine oxidase inhibitor eg Allopurinol,
Febuxostat,
Uricosuric agents eg sulphinpyrazone, probenecid, benzbromarone,
Canakinumab

Question 14

What are the rules of lowering uric acid levels?

Answer 14

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

Question 15

What is pseudogout?

Answer 15

Gout of the knee most commonly in elderly females and has erratic flares

Question 16

Aetiology of pseudogout

Answer 16

Idiopathic, familial, metabolic

Question 17

Triggers of pseudogout?

Answer 17

Trauma, intercurrent illness

Question 18

Management of pseudogout

Answer 18

NSAIDs, steroids

Question 19

Polymyalgia rheumatica presentation

Answer 19

Sudden onset of shoulder +/- pelvic girdle stiffness in >50year old paitient, 
Anaemia, 
Malaise, 
Weight loss, 
Fever, 
Depression, 
Arthralgia/ synovitis

Question 20

Investigations for polymyalgia rheumatica?

Answer 20

ESR (>50),

Steroid response

Question 21

Differential diagnosis of polymyalgia rheumatica

Answer 21

Myalgic onset inflammatory joint disease, 
Underlying malignancy, 
Inflammatory muscle disease, 
Hypo/ hyperthyroidism, 
Bilateral shoulder capsulitis, 
Fibromyalgia

Question 22

Treatment of polymyalgia rheumatica?

Answer 22

Prednisone 15mg per day (18-24 month course),

Bone prophylaxis