Markedly elevated intra-articular white cell count caused by gout alone

Area of Science:

• Rheumatology
• Orthopedics
• Infectious Diseases

Background:

• Septic arthritis diagnosis relies heavily on synovial fluid analysis, particularly white blood cell (WBC) counts.
• Elevated WBC counts (>50,000 cells/µL) traditionally suggest infection, often necessitating urgent intervention.

Observation:

• Two cases presented with exceptionally high synovial fluid WBC counts (168,500 and 500,000 cells/µL).
• Despite these counts, neither patient had septic arthritis; instead, both had gout with monosodium urate crystals.

Findings:

• These cases represent the highest reported synovial fluid WBC counts in gout patients.
• The findings challenge the strict reliance on WBC count alone for diagnosing septic arthritis.

Implications:

• Markedly elevated synovial fluid WBC counts can be seen in acute gout, mimicking infection.
• Differentiating gout from septic arthritis requires comprehensive analysis, including crystal identification, even with very high WBC counts.