Preliminary evaluation of UF-5000 Body Fluid Mode for automated cerebrospinal fluid cell counting

Background: Cellular analysis of cerebrospinal fluid (CSF) provides important diagnostic information in various medical conditions. The aim of this study was to evaluate the application of Sysmex UF-5000 body fluid mode in cytometric analysis of CSF compared to Light Microscopic (LM). Methods: Eighty-one consecutive CSF samples were analyzed by UF-5000 body fluid mode and by LM. The study also included the evaluation of: limit of Blank (LoB), limit of Detection (LoD), limit of Quantitation (LoQ), carryover and linearity. Results: For total nucleated cells (TNC-UF) and white blood cells (WBC-UF) LoB, LoD and LoQ were 1 x 10(6) cells/L, 1.8 x 10(6) cells/L and 1.9 x 10(6) cells/L respectively. For red blood cells (RBC) LoB was 2 x 10(6) cells/L, LoD was 3.5 x 10(6) cells/L and LoQ was 14 x 10(6) cells/L respectively. Linearity was excellent, carryover was negligible. The agreement between UF-5000 body fluid mode parameters and manual cell counts was good in all CSF samples with bias ranged between -0.5 and 25.1 x 10(6) cells/L. The ROC curve analysis showed an area under curve of 0.99 for both TNC-UF and WBC-UF parameters. Conclusions: The UF-5000 body fluid mode offers rapid and accurate counts in clinically relevant concentration ranges, replacing the LM for most samples. However, in samples with abnormal cell counts or with abnormal scattergram the need for microscopic review remains.