Crystalline Arthropathies

Question 1

what is hyperuricemia?

Answer 1

serum urate values >6.8 mg/dl

Question 2

what is gout?

Answer 2

inflammatory arthritis developing as a consequence of urate deposition in the joint

Question 3

where does most acute gouty arthritis occur?

Answer 3

1st MTP (podagra)- (90% )

Question 4

what is the order of freuqnecy of joints involved?

Answer 4

1. 1st MTP
2. mid-foot
3. ankle
4. heel
5. knee
6. wrist
   7;. finger
7. elbow

Question 5

what are the 4 stages of gout?

Answer 5

1. asymptomatic hyperuricemia
2. acute flares
3. intercritical segments
4. advanced gout

Question 6

what is asymptomatic hyperuricemia?

Answer 6

elevated serum urate with no clinical manifestations of gout

Question 7

what happens in acute flares stage of gout?

Answer 7

acute inflammation in the joint caused by urate crystallization

Question 8

what happens in intercritical segments?

Answer 8

the intervals btwn acute flares

Question 9

what happens in advanced gout?

Answer 9

long-term gouty complications of uncontroleld hyperuricemia

Question 10

what are some pathognomonmic changes of gouty tophus on radiograph?

Answer 10

“overhanging edges” with periarticular erosions

Question 11

why is gout on the rise?

Answer 11

• increased longevity
• aging population
• increased comorbidity
• low dose aspirin
• thiazides
• fructose intake

Question 12

which degradation pathway produces uric acid?

Answer 12

purine degradation

Question 13

which enzyme is targeted for treatment of gout because it catalyzes the final conversion to uric acid?

Answer 13

xanthine oxidase

Question 14

at what level does urate crystallize?

Answer 14

at a level of 6.8 mg/dL

Question 15

which medications are risk factors for development of gout?

Answer 15

1. diuretics- lead to increased uric acid reabsorption
   2, low dose aspirin- increased serum urate and decreased uric acid clearance
2. pyrazinamide, ethambutol, niacin- gout observed at higher incidence

Question 16

which patient population is at risk for development of gout?

Answer 16

transplant patients

bc they are often on calcineurin inhibitors that put them at risk for hyperuricemia

Question 17

which drug is a contrindication to allopurinol use?

Answer 17

azathioprine

*bc it needs xanthine oxidase, which allopurinol blocks

Question 18

people who have gout often have what other disease?

Answer 18

obesity
metabolic syndrome
Diabetes mellitus
heart failure
hyperlipidemia
hypertension

Question 19

what is the gold standard for diagnosing gout?

Answer 19

synovial fluid analysis- visualizing MSU crystals

Question 20

how would you describe gout crystals?

Answer 20

negatively birefringent under polarized light

Question 21

what acute changes are seen in gout radiographs?

Answer 21

acutely, often only soft tissue swelling is seen

Question 22

what chronic changes are seen in gout radiographs?

Answer 22

• “overhanging edges”
• erosions w/ demarcated round deficits with sclerotic margins
• very destructive

Question 23

how do you terminate acute flare?

Answer 23

1. control crystal-induced inflammation and pain using NSAIDs, colchicine, steroids

Question 24

what are the critical considerations for terminating the acute flare?

Answer 24

• rapid initiation of therapy

- appropriate duration of therapy

Question 25

which drug to treat gout-inflammation is contraindicated in dialysis patients?

Answer 25

colchicine

Question 26

which drug should not be given thru IV?

Answer 26

colchicine

Question 27

what is the first-line treatment for gout?

Answer 27

intraarticular corticosteroids

Question 28

what are 2 approved urate-lowering agents for gout?

Answer 28

uricosuric agents

xanthine oxidase inhibitor (allopurinol & febuxostat)

Question 29

what are the limitations of uricosuric agents like probenecid?

Answer 29

• efficacy dependent on functioning kidneys (Crcl>50 mL/min)
• 2x a day dosing
• risk of UA crystallization, stone formation

Question 30

what are the advantages of xanthine oxidase inhibitors?

Answer 30

• single daily dose
• efficacious in patients w/ renal insufficiency
• effective for both overproducers and underexcretors

Question 31

what is the #1 side effect of allopurinol?

Answer 31

ironically, it is gout flares.

lowering serum urate mobilizes deposited crystals

Question 32

what are the drug interactions with allopurinol?

Answer 32

azathioprine

6-mercaptopurine

Question 33

what is the 2nd most common side effect of allopurinol?

Answer 33

severe hypersensitivity syndrome (a rash that occurs early on in treatment)

Question 34

what are prophylactic treatments for gout flares?

Answer 34

NSAIDs, colchicine

*initiate agents prior to starting urate-lowering therapy

Question 35

what is the formation of CPPD crystals in articular hyaline and fibrocartilage called?

Answer 35

CPPD deposition disease

Question 36

what is the CPPD -crystals induced inflammation called?

Answer 36

pseudogout

Question 37

what is severe, atypically distributed structural joint damage called?

Answer 37

pyrophosphate arthropathy

Question 38

what is pathologically or radiologically evident cartilage calcification called?

Answer 38

chondrocalcinosis

Question 39

what age population gets pseudogouts?

Answer 39

elderly , 80-90 y/o

Question 40

which metabolic disease is associated with CPPD?

Answer 40

hemachromatosis

Question 41

what is the order of likelihood that psuedogout affects joints?

Answer 41

knees
wrists
shoulders
ankles

Question 42

describe the cryastals in pseudogout

Answer 42

blue (+) birefringent crystals

Question 43

describe treatment for CPPD.

Answer 43

no mechanis, to reduce CPPD crystal load so is more frustrating to treat