Arthritis

• Cellulitis
• Septic arthritis
• Pseudogout
• Rheumatoid arthritis
• Reactive arthritis (Reiter’s syndrome)
• Osteoarthritis
• Chronic lead poisoning (saturnine gout)
• Palindromic rheumatism

Podagra

• Trauma
• Cellulitis
• Sarcoidosis
• Pseudogout
• Psoriatic arthritis
• Bursitis of first metatarsophalangeal (MTP) joint (inflamed bunion)

Tophi

• Rheumatoid nodules
• Erythema nodosum
• Gout
• Coccidioidomycosis
• Endocarditis (Osler’s nodes)
• Sarcoidosis
• Polyarteritis nodosa

• Acute monoarthritis
• Hyperuricemia, endogenous
• Purine content of foods
• Urinary calculi
• Arthritis, general DDx
• Joint pain and fever

• Primary, especially Pacific islanders
• Secondary (acquired hyperuricemia):
  • Drugs, eg, alcohol, diuretics, low-dose aspirin, niacin, cyclosporine
  • Myeloproliferative disease, multiple myeloma, hemoglobinopathy, chronic renal disease, hypothyroidism, psoriasis, sarcoidosis, lead poisoning