血细胞分析仪计数血小板假性减少原因分析及对策探讨

目的探讨血细胞分析仪计数血小板(PLT)假性减少的原因及处理对策。方法对Beckman LH780自动血细胞分析仪计数PLT100×109/L的351例样本进行手工稀释计数及涂片染色镜检,按血小板直方图类型分组,A组(正常血小板直方图):297例;B组(小血小板直方图):13例;C组(大血小板直方图):11例;D组(血小板聚积直方图):19例;E组(红细胞碎片直方图):11例,对血细胞分析仪计数与手工稀释计数进行比较,并与涂片染色镜检进行相符程度比较。结果①与手工稀释计数比较,A、B组血细胞分析仪PLT计数无显著差异(P0.05);C、D组血细胞分析仪PLT计数减少,有显著性差异(P0.01);E组血细胞分析仪PLT计数增高,有显著性差异(P0.01)。②手工稀释计数比血细胞分析仪计数与涂片染色镜检结果相符程度高。③30例血小板假性减少的样本中,7例EDTA依赖性假性PLT减少(EDTA-PTCP);8例采血不顺造成;4例冷凝集;大血小板及红细胞碎片11例。结论血细胞分析仪计数血小板有可能出现血小板计数假性减少,对血小板直方图异常的样本必须进行手工稀释计数和涂片染色镜检来提高血小板报告的准确性。

Analysis on causes and countermeasures on pseudo - reduction of platelet count by blood cell analyzer

Objective To explore the causes and treatment strategies for pseudo - reduction of platelet count by blood cell analyzer. Methods A total of 351 blood samples for platelet count less than 100×109 / L measured by Beckman LH780 automatic blood cell analyzer were re - examined by handmade dilute count and smear staining for microscopy. They were divided into 5 groups according to platelet histogram,297 specimens with normal platelet histogram were allocated in group A;13 specimens with small platelet histogram in group B：11 specimens with large platelet histogram in group C：19 specimens with platelet aggregation histogram in group D,and 11 specimens with red cell fragments histo-gram in group E. The platelet count by blood cell analyzer and handmade dilute count were compared with smear staining examination under mi-croscopy for degree of coincidence. Results ① In comparison with handmade dilute count,the difference between group A and group B was not statistically significant（ P ﹥ 0. 05）,the difference between group C and group D was statistically significant（ P 〈 0. 01）,and the platelet count with blood cell analyzer was higher in group E,and the difference between group E and other groups was statistically significant（ P 〈 0. 01）. ②There was high degree of coincidence in results between handmade dilution count and smear staining examination under microscopy . Conclusion Platelet count by blood cell analyzer may be pseudo - reduced. In order to raise the accuracy of platelet count,the samples with abnormal platelet histogram need to be checked by handmade dilute count and smear staining examination under microscopy.