Optimization of Cellular analysis of Synovial Fluids by optical microscopy and automated count using the Sysmex XN...

This study was planned to assess the impact of pre-treating synovial fluid (SF) samples with hyaluronidase (HY), defining the best procedure for optical microscopy (OM) analysis and evaluating the performance of Sysmex XN-9000 Body Fluid module (XN-BF).

The cell count by OM was carried out both with and without HY pre-treatment, and using 3 different types of staining reagents. The evaluation of XN-BF included data comparison with OM (100 SFs), carryover, Limit of Blank (LoB), Limit of Detection (LoD), Limit of Quantitation (LoQ) and linearity.

Unlike cell count in Burker's chamber and staining with Stromatol, pre-treatment with HY and staining with Methylene Blue and Turk's promoted cell clustering. The SF samples pre-treated with HY displayed excellent morphological quality, contrary to samples without HY pre-treatment. Excellent correlation was found between total cells counting with both OM and XN-BF. Satisfactory agreement was also observed between polymorphonuclear neutrophils compared to XN-BF parameter, whereas mononuclear cell count on XN-BF had suboptimal agreement with OM. The carryover was negligible. The LoB, LoD, LoQ and linearity were excellent.

XN-BF displays excellent performance, which makes it a reliable and practical alternative to OM for SF samples analysis in clinical laboratories.