Abstract:

Objective　To establish and validate the re-examination rules for the ORIENTER FA280S fully automatic feces analyzer at the Dadelu Main Hospital of The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, and to improve the efficacy of routine and occult blood testing in feces samples. Methods　A total of 500 routine feces samples were randomly collected from the Dadelu Main Hospital of The Second Affiliated Hospital of Guangzhou University of Chinese Medicine between March 1 and May 31, 2024. These samples were tested using the ORIENTER FA280S fully automatic feces analyzer, with manual microscopic examination as the gold standard. χ² test was conducted to compare the results of instrumental analysis and manual smear microscopic examination, allowing for the screening of re-examination rules for the fully automatic feces analyzer. To validate the re-examination rules, 248 true-positive feces samples for any test item were collected between June 1 and August 31, 2024, and the missed detection rate was calculated. The re-examination rules were evaluated against internationally accepted criteria (false negative rate <5%). Results　For the group used to establish re-examination rules, the positive rates for red blood cells, white blood cells, fungi, parasite eggs, and occult blood test were 5.6% (28/500) , 5.6% (28/500), 4.4% (22/500), 7.2% (36/500), and 24.8% (124/500), respectively. For the validation group, the positive rates for red blood cells, white blood cells, fungi, parasite eggs, and occult blood test were 18.55% (46/248), 29.03% (72/248), 9.27% (23/248), 22.18% (55/248), and 67.34% (167/248), respectively. Five re-examination rules formulated were as below: ⑴ microscopic examination was taken when feces were loose/watery, and red/white blood cells or fungi were negative; ⑵ high-power microscopic review was done when parasites or eggs were reported by the instrument and confirmed by the analyzer's high power field and if the analyzer's field was blur; ⑶ microscopic examination for suspected red/white blood cells or fungi; ⑷ chemical re-test for occult blood was done when feces were dark, brown, or black, and the occult blood test was negative; ⑸ gold standard re-test for occult blood was done when red blood cells were positive, but the occult blood test was negative. The false negative rate for the validated re-examination rules was 4.03% (10/248), lower than 5.00%. Conclusion These rules effectively control the false negative rate, meet international standards, and satisfy testing requirements.

Key words: ORIENTER FA280S,  Re-examination rules,  Fecal routine,  Occult blood test

摘要：

目的　建立并验证适用于广州中医药大学第二附属医院大德路总院基于沃文特FA280S全自动粪便分析仪的复检规则，提高粪便常规与隐血检查项目检测的效能。方法　2024年3月1日至5月31日随机收集广州中医药大学第二附属医院大德路总院500份粪便常规标本，采用沃文特FA280S全自动粪便分析仪检测，并以人工镜检验证的结果为标准。采用χ2检验对比仪器分析和人工涂片镜检结果，筛选出全自动粪便分析仪的复检规则。2024年6月1日至8月31日再次收集248例任一项目真阳性粪便标本数据计算漏检率，验证复检规则，通过国际通用复检规则评估指标（假阴性率<5%）。结果　建立复检规则组红细胞、白细胞、真菌、寄生虫卵、隐血试验阳性率分别为5.6%（28/500）、5.6%（28/500）、4.4%（22/500）、7.2%（36/500）、24.8%（124/500）。验证复检规则组红细胞、白细胞、真菌、寄生虫卵、隐血试验阳性率分别为18.55%（46/248）、29.03%（72/248）、9.27%（23/248）、22.18%（55/248）、67.34%（167/248）。制定5项复检规则：⑴当粪便性状呈稀便或烂便、红（白）细胞或真菌阴性时，人工涂片显微镜复检；⑵当仪器显示查见寄生虫或寄生虫卵时，仪器高倍镜视野下确认，若仪器视野模糊，人工涂片显微镜高倍镜下确认；⑶当仪器提示可疑红（白）细胞或真菌时，人工涂片显微镜下确认；⑷当粪便颜色深，褐色或黑色时，隐血试验阴性时，复检粪便隐血化学法；⑸当粪便红细胞阳性，隐血试验阴性时，复检粪便隐血试验金标准法。复检规则验证假阴性率为4.03%（10/248），低于5.00%。结论　该规则可有效控制假阴性率，符合国际标准，满足检验需求。

关键词: 沃文特FA280S； ,  , 复检规则； ,  , 粪便常规； ,  , 隐血试验