Crystal Arthropathies & Other Joint Conditions

Question 1

Crystal Induced Arthropathy-General

Answer 1

• Gout
  
  • Monosodium urate monohydrate
• Pseudogout
  
  • Calcium pyrophosphate dihydrate
• Basic calcium phosphate
• Inflammatory arthritis
• Episodic and acute
  
  • Chronic can occur
• Crystals ingested by monocytes leading to recruitment of neutrophils

Question 2

Crystal Arthropathy

Answer 2

• Gout
  
  • 3% of genpop (8mill)
  • MALES >> Females
  • Age 65 and older: 4.9%
  • Ages 20-49: 0.9%
• Chronic hyperuricemia
  
  • 6.8 mg/dL
• Women protected by uricosuric effect of estrogens
• Additional risk factors: obesity, metabolic syndrome, diet (high purine diet, fructose), medications (thiazide diuretics & low dose aspirin)

Question 3

Gout-General

Answer 3

• Supersaturation of uric acid
• Crystal formation
• Crystals active immune system
  
  • Trigger complement cascade which recruits neutrophils
  • Phagocytosis by monocytes activates intracellular inflammasome
• Inflammasome activation leads to increased IL-1b