Flow cytometry is widely used in many laboratories for automated nucleated cell counts and their differentiation in body fluids. The implementation of new reflex testing rules on these automated instruments could open new frontiers in laboratory workflow, improving characterization of body fluids and clinical diagnosis and decreasing costs. Ascitic (150) and pleural (33) fluids were collected and assessed by XE-5000 and optical microscopy. Cell counts performed with the methods showed a Pearson's correlation of 0.98 (p < 0.0001), Passing-Bablok regression y = 0.99x + 2.44, and bias of 32.3. In ascitic fluids, the best diagnostic performance was found for polymorphonuclear and neutrophil counts on XE-5000, which exhibited areas under the curve (AUCs) 0.98 (p < 0.0001) and 0.99 (p < 0.0001), respectively. In pleural fluids the best diagnostic performance was found for polymorphonuclear percent parameter, which displayed 0.97 (p < 0.0001). Specific reflex test rules based on these parameters were characterized by 92% diagnostic concordance, 1.00 sensitivity, and 0.84 specificity with optical microscopy. The application of a set of reflex testing rules may improve the diagnostic performance of XE-5000, increasing its reliability for routine automated cell count in body fluids. We acknowledge that further studies should be planned to validate our findings according to clinical data.
SummaryBackground: 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. Methods: We analyzed 77 consecutive CSF samples, 34 of which (44%) displayed leukocyte count >5 white blood cell (WBC)/mL 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/mL 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/mL. 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. Results: Optimal correlation was found between UF-1000i and optical microscopy, displaying Pearson's correlation of 0.99 and mean bias of -3.5 WBC/mL (95% CI, from -7.0 to 0.0 WBC/mL). Imprecision varied between 12 and 16%. Linearity was excellent, 4-278 WBC/mL. Carry-over was negligible. ROC analysis yielded AUC of 0.99 for both WBC and bacterial counts. The agreement at threshold >4 WBC/mL was 0.91, with sensitivity and specificity of 1.00 and 0.84. At
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.