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Flashcards in Crystal Deposition Diseases Deck (33):
1

What are the 3 common crystal depositions in crystal deposition disease?

Monosodium urate -> Gout

Calcium Phosphate dihydrate (CPPD) -> Pseudogout

Basic calcium phosphate hydroxy-apatite (BCP) -> Calcific Periarthritis/ Tendonitis

2

What will a gout joint look like?

Erythema
Swelling
Shiny

(may look sort of like cellulitis or septic arthritis)

3

What is an accumulation of uric acid called?

Tophus or Tophi (pleural)

4

Where on the face is a classic place to look in gout?

Ears

5

Describe purine input and metabolism

(where does our purine source come from and where does it go?)

Purines make DNA and RNA

These can be broken down to purines. This source can be supplemented by diet.

Purines are broken down to hypoxanthine. This can either be converted back into purines by HGPRT or can be broken down further to xanthine.

Xanthine is broken down into plasma urate which is excreted by the kidneys as uric acid.

6

What two broad ways can hyperuricaemia occur?

(think simple and broad)

Overproduction
Under production

7

List causes of overproduction of plasma urate (hyperuricaemia)

Malignancy e.g. lymphoproliferative, tumour lysis syndrome

Severe exfoliative psoriasis

Drugs e.g. ethanol, cytotoxic drugs

Inborn errors of metabolism

HGPRT deficiency

8

List causes of underproduction of plasma urate (hyperuricaemia)

Renal impairment

Hypertension

Hypothyroidism

Drugs e.g. alcohol, low dose aspirin, diuretics, cyclosporin

Exercise, starvation, dehydration

Lead poisoning

9

Lesch Nyan Syndrome is caused by a deficiency in what enzyme?

HGPRT

hypoxanthine-guanine phosphoribosyl transferase

10

What is the genotype of Lesch Nyan Syndrome?

X-linked recessive

11

What are the signs and symptoms of Lesch Nyan Syndrome?

Intellectual disability

Aggressive and impulsive behaviour

Self mutilation

Gout

Renal disease

12

What kinds of things precipitate gout?

Being Male (usually older)
Rich red meat diet
Beer
Exercise and dehydration
Out in the sun a lot
Diuretics

13

Why is gout rare in younger women?

Oestrogen has a uricosuric effect, making gout very rare in younger women.

However, after the menopause, urate levels rise and gout becomes increasingly prevalent.

14

What kind of history does gout give?

Very short onset

Go to bed with joints not feeling quite right

Wake up with joint(s) being red hot and inflamed

15

What is the main diagnostic test for gout?

Aspiration and microscopy

(needle shape crystals)

16

What blood test can you do in gout?

Serum uric acid
(not diagnostic)

17

How do you treat an acute flare of gout?

NSAIDs

Colchicine

Steroids I/A, I/M, oral

18

When would you treat hyperuricaemia?

1st attack not treated unless:
-Single attack of polyarticular gout
-Tophaceous gout
-Urate calculi
-Renal insufficiency

2nd attack treated if within 1yr

Prophylactically prior to treating certain malignancies

DO NOT treat asymptomatic hyperuricaemia

19

What treatments can lower uric acid?

Xanthine oxidase inhibitor
-e.g. Allopurinol

Febuxostat

Uricosuric agents
-e.g. sulphinpyrazone, probenecid, benzbromarone

IL-1 antagonist
-Canakinumab

20

What do you need to remember before starting to lower uric acid levels?

Wait until the acute attack has settles before attempting to reduce the urate level
-i.e. couple of weeks

Use prphylactic NSAIDs or low dose colchicine until urate level normal

21

What lifestyle factors need to be addressed in gout?

(what can you recommend?)

Address cardiovascular risk factors
-Food, alcohol, diabetes etc

Lots of water
Fruit like cheries
Low fat

22

What is the important joint in pseudogout compared to gout?

The knee is to pseudogout as the toe is to gout

23

Who usually gets pseudogout?

Elderly females

(gout = elderly males)

24

What are the aetiology and triggers of pseudogout?

Aetiology
-idiopathic, familial, metabolic

Triggers
-Trauma, Intercurrent illness

25

What is chondrocalcinosis?

Calcium pyrophosphate dihyrate (CPPD) crystal deposition

26

How do you manage pseudogout?

NSAIDs
I/A steroids

(no prophylactic therapies)

27

Who does polymyalgia rheumatica usually affect?

(what is the epidaemiology)

Elderly women
-Usually >70
-Rare

28

What is polymyalgia rheumatica associated with?

How many patiens with PMR have this condition?

How many with this condition have PMR?

Giant Cell Arteritis

20% of patients with PMR may have evidence of GCA

50% of patients with GCA may have PMR

29

Polymyalgia rheumatica and giant cell arteritis exist in a spiral with what?

Polymyalgia rheumatica -> giant cell arteritis -> High ESR and Anaemia

30

What are the classic symptoms of polymyalgia rheumatica?

What are the signs?

SUDDEN onset of shoulder +/- pelvic girdle STIFFNESS

ESR usually >45 often 100

-Anaemia
-Malaise; weight loss; fever; depression
-Arthralgia/ synovitis occasionally

31

how do you diagnose polymyalgia rheumatica?

Compatible history

Age >50

ESR >50

Dramatic steroid response
-24-48hrs and feels much much better

No specific diagnostic test

32

What is the differential diagnosis for polymyalgia rheumatica?

Myalgic onset inflammatory joint disease

Underlying malignancy
-e.g. multiple myeloma, lung cancer

Inflammatory muscle disease

Hypo-hyperthyroidism

Bilateral shoulder capsulitis

Fibromyalgia

33

What is the treatment for polymyalgia rheumatica?

Prednisolone 15mg per day initially
-18-24 month course

Bone prophylaxis