ANALYTICAL AND CLINICAL EVALUATION OF SYSMEX UF1000I FOR AUTOMATED SCREENING OF CEREBROSPINAL FLUIDS

作者:Buoro Sabrina; Ottomano Cosimo; Esposito Sara Appassiti; Gherardi Patrizia; Alessio Maria Grazia; Crippa Alberto; Farina Claudio; Raglio Annibale; Lippi Giuseppe*
来源:Journal of Medical Biochemistry, 2014, 33(2): 191-196.
DOI:10.2478/jomb-2013-0034

摘要

Background: We evaluated the performance of Sysmex UF1000i for cell counting and differential cell count, as well as for assessment of bacteria load in cerebrospinal fluid (CSF), as a potential approach for the rapid screening of meningitis or bacterial encephalitis. %26lt;br%26gt;Methods: We analyzed 77 consecutive CSF samples, 34 of which (44%) displayed leukocyte count %26gt; 5 white blood cell (WBC)/mu L with optical microscopy. Results on the UF-1000i were compared with those obtained by microscopic analysis. Imprecision was evaluated by testing three CSF samples with leukocyte values between 3.5 and 28.8 WBC/mu L in 10 replicates. Carry-over was evaluated with the Broughton formula on three CSF pools with leukocyte counts between 93.5 and 132.5 WBC/mu L. Linearity was assessed according to CLSI document EP6-A. In the presence of bacteria, identification and antibiogram were performed with Vitex (Biomerieux), except for Neisserie meningitidis (ApiNH, Biomerieux). Sensitivity tests were performed with Vitex and disc diffusion. %26lt;br%26gt;Results: Optimal correlation was found between UF-1000i and optical microscopy, displaying Pearson%26apos;s correlation of 0.99 and mean bias of -3.5 WBC/mu L (95% Cl, from -7.0 to 0.0 WBC/mu L). Imprecision varied between 12 and 16%. Linearity was excellent, 4-278 WBC/mu L. Carry-over was negligible. ROC analysis yielded AUC of 0.99 for both WBC and bacterial counts. The agreement at threshold %26gt; 4 WBC/mu L was 0.91, with sensitivity and specificity of 1.00 and 0.84. At %26lt;= bacteria/mu L cut-off, accuracy was 0.98, sensitivity 1.00 and specificity 0.97. %26lt;br%26gt;Conclusions: According to these results, CSF screening with UF-1000i seems a reliable approach in terms of instrument performance, turnaround time and overall laboratory efficiency.

  • 出版日期2014-6