A New Automated Technology for Cerebrospinal Fluid Cell Counts: Comparison of Accuracy and Clinical Impact of GloCyte, Sysmex XN, and Manual Methods.

Objectives: The purpose of the study was to compare the performance of GloCyte (Advanced Instruments, Norwood, MA), a new semiautomated instrument for cerebrospinal fluid cell counting, with the manual hemocytometer method and the automated Sysmex XN (Sysmex, Kobe, Japan) body fluid mode. The clinical impact of replacing the manual method with either automated method was determined.

Methods: Fifty-seven samples from 38 patients were analyzed by all three methods. Pearson correlation and Passing-Bablok regression were used to compare methods. Cytospin smears were reviewed on all samples, and clinical histories were obtained.

Results: There was a strong linear relationship between the manual and automated methods for WBC counts ( R  = 0.988 for GloCyte; R  = 0.980 for Sysmex XN). Positive bias was absent or negligible for WBC counts less than 30/μL. GloCyte and manual RBC counts were equivalent. There were no samples for which replacement of manual WBC counts by automated counts would have changed the diagnosis. Both automated methods showed improved precision for WBC counts compared with the manual method.

Conclusions: Replacing manual WBC counts by GloCyte or Sysmex XN WBC counts would improve consistency of results without compromising diagnostic accuracy.