[Reference intervals and its verification for leukocyte differential count in peripheral blood by CytoDiff flow cytometry].

OBJECTIVE

To establish and verify the reference intervals for leukocyte differential count in peripheral blood by CytoDiff flow cytometry.

METHODS

Leukocyte differentiation count was analyzed by using hematology analyzer, CytoDiff flow cytometry and morphology differential count in 278 healthy controls, 550 flagged and 102 unflagged samples. The reference intervals of leukocyte parameters were established and verified according to the healthy controls. Then the correlations of five leukocytes were analyzed among hematology analyzer, CytoDiff flow cytometry and morphology differential count. Lymphocyte subsets were analyzed and compared between healthy controls and patients with different diseases. The CytoDiff flow cytometric blast counts were explored to analyze the clinical diagnostic efficiency compared to morphology differential count as a reference method.

RESULTS

CytoDiff flow cytometry can differentiate the leukocyte into 16 parameters, including percentage and absolute count, therefore 32 parameters in total. Among these parameters, 18 parameters had significant difference between male and female (P < 0. 05), and the others had no difference (P >0. 05). Except the CD16pos monocyte, there were no difference among ages in other parameters. The correlation between hematology analyzer, CytoDiff flow cytometry and morphology differential count were good for neutrophils, lymphocytes, monocytes, basophils and eosinophils in healthy controls and clinical samples. When the cutoff value of the ratio of T + NK and B lymphocyte was set at 1. 0 by ROC, the sensitivity was 90. 9% and specificity was 99. 8% for diagnosing the chronic lymphocyte leukemia (CLL). When the cutoff value of blast count by CytoDiff flow cytometry was set at 1%, the sensitivity was 100%, specificity was 96. 1% and accuracy was 96. 2% by morphology differential blast count for the reference method.

CONCLUSIONS

Establish and verify the reference interval of leukocyte differential count in peripheral blood by CytoDiff flow cytometry in the adults of Beijing region. CytoDiff flow cytometry provide more parameters than hematology analyzer and morphology differential count, and therefore have excellent clinical diagnostic efficiency, especially for CLL and blasts from acute leukemia.