Evaluation of the interference of platelets in reticulocyte counting by flow cytometry using thiazole orange

Avaliação da interferência de plaquetas na contagem de reticulócitos por citometria de fluxo, utilizando laranja de tiazol

ABSTRACT

Introduction:

The reticulocyte count by flow cytometry (FC) - an automated counting method - can present errors due to the presence of interfering factors, contributing to a slight increase in results. However, automated methods have large advantages over the manual method, taken as reference, what justifies efforts to improve their quality.

Objective:

Evaluate platelet interference with the reticulocyte count by FC, using thiazole orange (TO) (FC/TO).

Materials and methods:

The method of reticulocyte count by FC/TO and a modified automated equivalent method, which excluded CD61-positive cells (platelets) from analysis (FC/TO/MOD), were compared to the manual method.

Conclusion:

Results were analyzed according to the recommendations of the Clinical and Laboratory Standards Institute (CLSI) to assess interchangeability between the methods, by linear regression analysis and paired t-test. The exclusion of interfering fragments from result analysis by the modified method produced results in closer proximity to those of the reference method.

Key words:
reticulocyte count; flow cytometry; blood platelets