湖北省2020—2021年疟疾诊断参比实验室血片镜检质量分析

目的 了解湖北省发热病人疟原虫血涂片制作质量和实验室人员疟原虫镜检能力水平,为消除疟疾后的有效监测提供技术保障。方法 对2020—2021年湖北省网络报告和疑似疟疾病例血片和随机抽取的各市州发热病人阴性血片进行镜检复核,对血片制作、染色、清洁度、镜检结果及虫种判定情况进行分析评价。结果 2020—2021年共复核疟原虫血片1 661张,制片、染色、清洁度总合格率分别为88.50%（1 470/1 661）、80.01%（1 329/1 661）、84.71%（1 407/1 661）。复核阳性病例63例,血片156张,阳性血片制片、染色、清洁度合格率分别是78.21%、76.92%、82.69%,阳性符合率为77.78%,虫种符合率为87.76%。恶性疟、间日疟、三日疟和卵形疟的虫种符合率分别为94.74%、90.00%、80.00%和80.00%。复核阴性血片1 505张,阴性血片制作、染色、清洁度合格率分别为89.57%、80.33%、84.92%,复核一致率为100%,未发现漏检。阴阳性血片制作合格率差异有统计学意义（χ²=17.933,P<0.05）,染色和清洁度合格率差异无统计学意义。血涂片质量主要存在的问题有沉渣较多、溶血不全、血膜制作不规范、染色深浅和厚血膜脱落。不同地区阴性血片质量差异有统计学意义（χ²_制作=73.109、χ²_染色=130.637、χ²_清洁度=68.806,P均<0.05）,且城市医院血片制作、染色和清洁度均优于乡镇卫生院（χ²_制作= 21.551、χ²_染色=13.561、χ²_清洁度=12.523,P均<0.05）。结论 湖北省各市州血涂片质量整体较好,阳性血片质量及疟原虫定性诊断能力有待进一步提高。

Quality of malaria blood smears of microscopic examinations in Hubei Provincial Malaria Diagnostic Reference Laboratory, 2020-2021

Objective To understand the quality of production of blood slides and laboratory personnel's ability to microscopically examine Plasmodium at Hubei Province clinic inspection stations at all levels,so as to provide the technical support for malaria surveillance in the post-elimination period. Methods The negative blood slides from patients with a fever in various cities (states) and all the positive blood slides of the direct report of the network and suspected cases were microscopic examination reviewed from 2020 to 2021,the staining and cleanliness of the blood smears,microscopic examination results and the coincidence rate of positive blood species were comprehensively analyzed and evaluated. Results A total of 1 661 checked blood smears were reexamined in the year of 2020 to 2021. The qualification rate of blood smears preparation, dyeing, cleanliness were 88.50%（1 470/1 661）, 80.01%（1 329/1 661）and 84.71%（1 407/1 661）, respectively. 63 positive cases and 156 positive blood slides were reviewed, the qualification rate of positive blood smears preparation, dyeing, cleanliness were 78.21%, 76.92%, 82.69%, with an overall coincidence of 77.78% for malaria diagnosis, and 87.76% for Plasmodium species identification. The coincidence rates of Plasmodium falciparum, Plasmodium vivax, Plasmodium ovale, Plasmodium malariae identification were 94.74%, 90.00%, 80.00% and 80.00% during the re-examinations, respectively. Totally 1 505 negative blood smears were reviewed, with a consistence rate of 100%. The qualified rates of blood smear preparation, dyeing, cleanliness were 89.57%, 80.33%, 84.92%, respectively, and there were no leak detection. There was significant difference in the qualification rate of negative and positive blood smears preparation (χ²=17.933, P<0.05), but there was no significant difference in dyeing and cleanliness. The main factors which affected the quality of blood smears were excessive sediment, hemolysis insufficiency, non-standard blood film production, depth and shallow colouring and the drop of thick blood membrane. There was an significant difference in the quality of negative blood slides among the different districts (χ²_production=73.109, χ²_dyeing=130.637, χ²_cleanliness=68.806, all P<0.05), and the production, dyeing and cleanliness in urban hospitals were better than those in township hospitals (χ²_production=21.551, χ²_dyeing=13.561, χ²_cleanliness=12.523, all P<0.05). Conclusions The quality of blood smears for Plasmodium detection in Hubei province is satisfying. But the positive blood slides quality and the qualitative diagnostic ability of Plasmodium in microscopy examination of positive cases should be improved in the future．