Brambila E, Castillo-Guerra R, Lozano-Zarain P

Language: Spanish
References: 16
Page: 4-12
PDF size: 364.59 Kb.

ABSTRACT

Introduction. Leukocyte differential counts, based in blood films is a routinely method in clinical laboratories, however, results are imprecise and biased, particularly for big cells and cells circulating in small number.
Objective. Comparison between results obtained from three manual methods, based in blood films review, and the results obtained from a cell auto-analyzer.
Material and methods. Two hundred specimens were used to prepare blood films using transversal, longitudinal and pen smears on slides methods. At the same time, leukocyte total number and differential counts from specimens were determined with an auto-analyzer. Statistical analysis included intra- and inter-individual variability, and method comparison was evaluated with paired t test, correlation and Deming regression analysis.
Results and Discussion. Intra- and inter-individual variability, as determined by the coefficient of variation, ranged between 5.7 and 77.5%, differences were dependent of cellular type and blood film preparation. Transversal and pen methods did not shown significant differences in polymorphonuclear and neutrophil leukocyte counts, however neutrophil number determined by longitudinal film method showed a significant difference, as compared with the automated method.
Conclusion. Independently of blood film preparation methods used, lymphocytes and monocytes number shown significant differences when were compared with an automated equipment.

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