Crystal Arthritis

Question 1

Most commonly affected joint (Gout vs. CPPD)

Answer 1

GOUT:
1st attack: meta-tarsal-phalangeal (MTP) joint (erythema and desquamation)

MTP > instep, ankle, knees > wrist, fingers, elbows

CPPD:
Knee (cartilage calcification) >

Question 2

Describe 4 clinical presentation of gout.

Answer 2

1. Asxs hyperuricemia (serum uric acid > 7.0 mg/dL)
2. Acute gout
3. Intercritical Period
4. Chronic tophaceous gout

Question 3

Describe 4 clinical presentations of Calcium pyrophosphate deposition dz (CPPD).

Answer 3

1. Acute CPP (Monoarthritis, esp. knee)
2. Osteoarthritis w/ CPP
3. Asymptomatic CPPD
4. Chronic CPP (polyarthritis of small joints - hands and feet, chondrocalcinosis)

Question 4

Describe gout crystals

Answer 4

Needle-shaped, negatively birefringent (“Parallel Yellow”)

Intracellular(?)

Question 5

Acute gout triggers

Answer 5

1. Alcohol + Dietary excess
2. Trauma
3. diuretic use (may cause hyperuricemia)

Question 6

Acute gout triggers

Answer 6

1. Alcohol + Dietary excess
2. Trauma
3. diuretic use (may cause hyperuricemia)
4. COLD
5. ↓ O2 tension

Question 7

Chronic gout features

Answer 7

1. Usu. polyarticular
2. Chronic inflammatory
3. Proportional of serum uric acid levels

Question 8

Chronic gout - extraarticular dzs

Answer 8

1. Renal
   - CKD (lower serum uric acid to ↓ time to CKD)
   - ACUTE URATE NEPHROPATHY (MSU crystals in tubules + ureters)
   - Risks for stones proportional to serum uric acid levels

Question 9

Most people are uric acid over-producers/underexcretors?

Answer 9

90% = UNDEREXCRETORS

Question 10

Baseline Recommendations for Pts w/ gout

Answer 10

1. Reduce OH consumption
2. Reduce high purine diet
3. Quit smoking
4. Lose wt.
5. Exercise

Question 11

Acute gout Rx

Answer 11

1. Colchicine (MECH OF ACTION?)
2. NSAIDs
3. Corticosteroids (prednisone)
4. Injection (must exclude infxn)

More severe gout:
1. Xanthine oxidase inhibitors (ALLOPURINOL target

Question 12

Describe CPP crystals

Answer 12

Rhomboid, blue
Positive Birefringent
ABC = Aligned Blue Calcium

Question 13

Acute CPPD Rx

Answer 13

1. Colchicine (MECH OF ACTION?)
2. NSAIDs -> hydroxychloroquine -> methotrexate
3. Corticosteroids (prednisone)
4. Injection (must exclude infxn)
5. Nothing yet removes/prevents deposition

Question 14

Differences between gout and CPPD

Answer 14

1. Crystal type
2. Articular area affected: MTP vs. knee
3. 20s vs. CPPD = associated with age