synovial fluid analysis
Pronunciation: sin-OH-vee-al
Laboratory examination of joint fluid to aid in diagnosis of arthritis and joint infections.
Full Definition
Synovial fluid analysis involves the laboratory examination of fluid obtained from a joint space through arthrocentesis to help differentiate between various causes of joint effusion. The analysis typically includes cell count with differential, glucose level, protein content, Gram stain, culture, and crystal examination. In pediatric rheumatology, synovial fluid analysis is crucial for distinguishing between infectious arthritis (which requires urgent antibiotic treatment), inflammatory arthritis, and mechanical joint problems. Normal synovial fluid is clear and viscous with low cell counts, while inflammatory conditions show increased white blood cell counts with neutrophilic predominance. The procedure is particularly important when evaluating monoarticular arthritis in children.
Usage
Usage note: Should always include cell count, Gram stain, and culture results in documentation.
In Context
- "Synovial fluid analysis revealed 50,000 white blood cells with 90% neutrophils, consistent with bacterial arthritis." — Laboratory report
- "The clear appearance and low cell count on synovial fluid analysis ruled out infectious etiology." — Clinical correlation note