Title: AB0198 Synovial fluid analysis ? a retrospective revision
Abstract: <h3>Background</h3> Synovial fluid analysis is an extension of the physical examination. In patients with crystal associated arthritis a few drops of synovial fluid often makes a definite diagnosis. <h3>Objectives</h3> The authors reviewed of synovial fluid analysis results of their Department. <h3>Methods</h3> A revision is made of all the synovial fluids seen under microscopic ordinary light, polarised light and with alizarin red stain, between the 1st. of September 1999 and the 31th of December 2000. The fluids were taken from in and outpatients of the Rheumatology Department of the Egas Moniz Hospital in Lisbon, who had a formal indication for arthrocentesis. <h3>Results</h3> A total of 114 synovial fluids were studied, 76 (66.7%) women and 38 (33.3%) men. The mean age was 60.8 ± 16.79 years. The synovial fluid was intra-articular in 76.8% and from adjacent bursal tissues in 23.2%. The mean time between arthrocentesis and microscopic analysis of the fluid was 4.72 ± 7.13 days. The fluid had mechanical properties in 32.5% of the cases; different types of crystals in 27.2%; inflammatory properties in 23.7%; 1.75% were traumatic: 0.88% were infectious; 14% were not classified. Half the patients didn’t have a previous diagnosis and the synovial fluid microscopic analysis made a definite diagnosis in 40.4% of these patients: 38.6% of crystal associated arthritis and 1.85% of septic arthritis. <h3>Conclusion</h3> The synovial fluid microscopic analysis made a definite diagnosis in 40,4% in patients without a previous one, confirming it is a useful tool in clinical practice.