迈瑞 BC-6800 血液分析仪提供的感染 RBC 标记/参数有助于疟疾的诊断。

Infected RBC flag/parameter provided by Mindray BC-6800 haematology analyzer aid the diagnosis of malaria.

机构信息

Department of Clinical Laboratory, Chinese People's Liberation Army General Hospital, Beijing, 100853, China.

Algorithm and Clinical Research Department, Haematology, IVD, Shenzhen Mindray Bio-Medical Electronics Co., Ltd, Shenzhen, 518057, China.

出版信息

Malar J. 2019 Jul 31;18(1):262. doi: 10.1186/s12936-019-2890-z.

DOI:10.1186/s12936-019-2890-z

PMID:31366365

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC6668162/

Abstract

BACKGROUND

The Mindray BC-6800 haematology analyzer (BC-6800) provides a dedicated flag 'Infected RBC' (InR) and the number of InR (InR#)/the permillage of InR (InR‰) in routine blood testing as a screening tool for malaria in endemic areas. This study sought to evaluate the effectiveness of the BC-6800 flag parameter for aiding the diagnosis of malaria.

METHODS

A total of 181 samples were tested using the Mindray BC-6800 haematology analyzer, including 117 malaria-infected samples collected from Yunnan, China, and 64 samples from healthy controls. Microscopy examination was conducted as reference when stained thick blood film revealed the presence of malaria parasites identified as Plasmodium vivax and Plasmodium falciparum. The receiver operating characteristic (ROC) curve analysis was developed using Analyse-it v4.92.3. The Kappa value was determined to evaluate the agreement between BC-6800 and light microscopy.

RESULTS

The sensitivity of InR‰ generated by BC-6800 for P. vivax and P. falciparum was 88.3 and 24.1%, respectively; specificity of InR‰ for malaria parasites was 84.3 and 84.3%, respectively; positive predictive value and negative predictive value was 89.4 and 82.7% for P. vivax, and 52.8 and 60.3% for P. falciparum. There was a strong correlation between ΔWBC and InR‰ (R = 0.9731 for P. vivax and R = 0.9757 for P. falciparum). There was also a significant correlation between parasitaemia and InR# in P. vivax-infected samples (R = 0.734). InR# was evaluated using ROC curve analysis, the area under the ROC curve is 0.95 with a 95% confidence interval of 0.926 to 0.974, and the cut-off value is 0.01 × 10/L for P. vivax. However, the ring stage and the early trophozoite stage of Plasmodium cannot be detected easily on BC-6800, possibly because of the small size and low nucleic acid content of these stages.

CONCLUSIONS

The findings suggest that the flag 'InR' and the parameters 'InR#/InR‰' provided by the BC-6800 haematology analyzer could be used to screen for malaria in a clinical setting.

摘要

背景

迈瑞 BC-6800 血液分析仪（BC-6800）提供了一个专用的标志“Infected RBC”（InR）以及 InR#/InR‰的数量（InR‰），作为疟疾流行地区常规血液检测的筛查工具。本研究旨在评估 BC-6800 标志参数在辅助疟疾诊断方面的有效性。

方法

共检测了 181 个样本，包括从中国云南采集的 117 个疟疾感染样本和 64 个健康对照组样本，均使用迈瑞 BC-6800 血液分析仪进行检测。当染色厚血膜显示存在间日疟原虫和恶性疟原虫时，采用显微镜检查作为参考。采用 Analyse-it v4.92.3 进行受试者工作特征（ROC）曲线分析。采用 Kappa 值评估 BC-6800 与显微镜检查的一致性。

结果

BC-6800 生成的 InR‰对间日疟原虫和恶性疟原虫的敏感性分别为 88.3%和 24.1%；对疟原虫的特异性分别为 84.3%和 84.3%；对间日疟原虫的阳性预测值和阴性预测值分别为 89.4%和 82.7%，对恶性疟原虫的阳性预测值和阴性预测值分别为 52.8%和 60.3%。ΔWBC 与 InR‰之间存在很强的相关性（R=0.9731 用于间日疟原虫，R=0.9757 用于恶性疟原虫）。在感染间日疟原虫的样本中，InR#与寄生虫血症之间也存在显著相关性（R=0.734）。采用 ROC 曲线分析评估 InR#，ROC 曲线下面积为 0.95，95%置信区间为 0.926 至 0.974，截断值为 0.01×10/L 用于间日疟原虫。然而，BC-6800 不能轻易检测到疟原虫的环体期和早期滋养体期，可能是因为这些阶段体积小且核酸含量低。