Crystal arthropathies and polymyalgia rheumatica

Question 1

What are crystal deposition diseases characterised by?

Answer 1

Deposition of mineralised material within joints and peri-articular tissue

Question 2

What are common mineralised material deposited in joints to cause crystal deposition diseases?

Answer 2

Monosodium urate = gout
Calcium pyrophosphate dehydrate (CPPD) = pseudogout
Basic calcium phosphate hydroxy-apatite (BCP) = calcific periarthritis/tendonitis

Question 3

What crystal deposition causes gout?

Answer 3

Monosodium urate

Question 4

What crystal deposition causes pseudogout?

Answer 4

Calcium pyrophosphate dihydrate (CPPD)

Question 5

What crystal deposition causes calcific periarthritis/tendonitis?

Answer 5

Basic calcium phosphate hydroxy-apatite (BCP)

Question 6

What are tophi?

Answer 6

Massive accumulations of uric acid

Question 7

What is uric acid an end product of metabolism-wise?

Answer 7

Purine metabolism

Question 8

What does too much uric acid cause?

Answer 8

Hyperuricemia

Question 9

What can increased production of purines cause?

Answer 9

Hyperuricemia -> gout attack

Question 10

What are the two main ways the hyperuricemia can occur?

Answer 10

Overproduction of uric acid

Under excretion of uric acid

Question 11

How can there be an overproduction which causes hyperuricemia?

Answer 11

Malignancy
Severe exfoliative psoriasis
Drugs e.g. ethanol, cytotoxic drugs
Inborn errors of metabolism
HGPRT deficiency

Question 12

What is more common: over production of uric acid or under excretion?

Answer 12

Under excretion

Question 13

What can cause under excretion of uric acid?

Answer 13

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

Question 14

What is Lesch Nyhan syndrome?

Answer 14

HGPRT deficiency

X-linked recessive

Question 15

What does HGPRT deficiency cause?

Answer 15

Causes a build-up of uric acid in all body fluids

Question 16

What are the signs/symptoms of Lesch Nyhan syndrome?

Answer 16

Intellectual disability
Aggressive/impulsive behaviour
Self mutilation
Gout
Renal disease

Question 17

Which sex is affected more by gout?

Answer 17

Men

Question 18

What are the signs/symptoms of gout?

Answer 18

Monoarthritis
Tophi
Inflammatory arthritis
Warm, tender, painful joints
Pyrexia
?Kidney stones

Question 19

Where is the most common place for crystal deposition in gout?

Answer 19

The MTP joint in the foot

Question 20

What are the investigations for gout?

Answer 20

Serum urate
WCC, ESR
Synovial fluid = arthrocentesis
XR

Question 21

What is arthrocentesis?

Answer 21

Synovial fluid aspiration

Question 22

What can be seen in synovial fluid in gout?

Answer 22

Needle-shaped, negatively birefringent monosodium urate crystals

Question 23

What is the management of gout?

Answer 23

Acute flare:
NSAIDs
Colchicine
Steroids

Question 24

When does the 1st attack of hyperuricemia need treated?

Answer 24

• single attack polyarticular gout
• tophaceous gout
• urate calculi
• renal insufficiency

Question 25

When does the 2nd attack of hyperuricemia need treated?

Answer 25

If 2nd attack within 1yr

Question 26

When should you not treat hyperuricemia?

Answer 26

Asymptomatic

Question 27

What are uric acid lowering medications?

Answer 27

Xanthine oxidase inhibitor = allopurinol Febuxostat Uricosuric agents (sulphinpyrazone, probenecid, benzbromarone) Canakinumab

Question 28

What is the main drug for preventing uric acid synthesis?

Answer 28

Allopurinol

Question 29

What are the rules for lowering uric acid levels?

Answer 29

Wait until acute attack settled Use prophylactic NSAIDs or low dose colchicine/steroids until rate level normal Adjust allopurinol dose according to renal function

Question 30

What are CVS and lifestyle factors that could be addressed for gout?

Answer 30

``` Alcohol Dietary excess Fasting/severe dieting Hydration Exercise Smoking BP ```

Question 31

Which group is pseudogout seen most commonly in?

Answer 31

Elderly females

Question 32

What is aetiology of pseudogout?

Answer 32

Idiopathic Familial Metabolic

Question 33

What are triggers for pseudogout?

Answer 33

Trauma | Intercurrent illness

Question 34

What is chonedrocalcinosis?

Answer 34

Calcification in hyaline and/or fibrocartilage

Question 35

What type of crystals are found in the joint aspiration of pseudogout?

Answer 35

CPPD crystals | Pyrophosphate crystals

Question 36

What type of birefringent are the crystals in pseudogout?

Answer 36

Positively birefringent

Question 37

What is the manangement for pseudogout?

Answer 37

NSAIDs | Intra-articular injection steroids

Question 38

What are the investigations for pseudogout?

Answer 38

Joint aspirations | XR

Question 39

What is polymyalgia rheumatica?

Answer 39

A common inflammatory condition which causes bilateral pain, typically worse in the morning and associated with morning stiffness, in the shoulder, neck and pelvic girdle

Question 40

What other conditions are associated with polymyalgia rheumatica?

Answer 40

Giant cell arteritis (GCA) High ESR Anemia

Question 41

What is the age on onset of polymyalgia rheumatica normally?

Answer 41

>70yrs

Question 42

Which sex is more common affected by polymyalgia rheumatica?

Answer 42

Females

Question 43

What is the ESR in polymyalgia rheumatica?

Answer 43

>45 often 100

Question 44

What are other signs/symptoms associated with polymyalgia rheumatica?

Answer 44

``` Anaemia Malaise Weight loss Fever Depresion Arthralgia/synovitis ```

Question 45

How do you make a diagnosis of polymyalgia rheumatica?

Answer 45

``` Compatible history >50yrs ESR >50 Dramatic steroid response Non specific diagnostic test ```

Question 46

What are differentials for polymyalgia rheumatica?

Answer 46

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

Question 47

What is the treatment for polymyalgia rheumatica?

Answer 47

Prednisolone | Bone prophylaxis