PDF(Pubmed)
Abstract：
UNASSIGNED: Multistep laboratory testing is recommended for the diagnosis of Clostridioides difficile infection (CDI). The aim of this study was to present the impact of multistep CDI diagnostic testing in an academic hospital system and evaluate the toxin B gene polymerase chain reaction (PCR) cycle threshold (Ct) values of PCR-positive tests.
UNASSIGNED: In October 2022, our system began reflex testing all PCR-positive stool samples with the C. DIFF QUIK CHEK COMPLETE (Techlab), an enzyme immunoassay-based test with results for the glutamate dehydrogenase antigen (GDH) and C difficile toxin A/B. Hospital-onset (HO) CDI and CDI antibiotic use before and after testing were tracked. Ct values were obtained from the Infectious Diseases Diagnostic Laboratory. Receiver operating curve analysis was used to examine the sensitivity and specificity for identifying GDH+/toxin+ and GDH-/toxin- at various Ct thresholds.
UNASSIGNED: The HO-CDI rate decreased from 0.352 cases per 1000 patient-days to 0.115 cases per 1000 patient-days post-reflex testing (P < .005). Anti-CDI antibiotics use decreased, but the decrease was not commensurate with CDI rates following reflex testing. PCR+/GDH+/toxin+ samples had a lower mean Ct value than PCR+/GDH-/toxin- samples (23.3 vs 33.5, P < .0001). A Ct value of 28.65 could distinguish between those 2 groups. Fifty-four percent of PCR+/GDH+/toxin- samples had a Ct value below that cut-off, suggesting the possibility of CDI with a negative toxin test.
UNASSIGNED: Reflex testing for a laboratory diagnosis of CDI results in rapid, systemwide decreases in the rate of HO-CDI. Additional research is needed to distinguish CDI from C difficile colonization in patients with discordant testing.
UNASSIGNED: In October 2022, our system began reflex testing all PCR-positive stool samples with the C. DIFF QUIK CHEK COMPLETE (Techlab), an enzyme immunoassay-based test with results for the glutamate dehydrogenase antigen (GDH) and C difficile toxin A/B. Hospital-onset (HO) CDI and CDI antibiotic use before and after testing were tracked. Ct values were obtained from the Infectious Diseases Diagnostic Laboratory. Receiver operating curve analysis was used to examine the sensitivity and specificity for identifying GDH+/toxin+ and GDH-/toxin- at various Ct thresholds.
UNASSIGNED: The HO-CDI rate decreased from 0.352 cases per 1000 patient-days to 0.115 cases per 1000 patient-days post-reflex testing (P < .005). Anti-CDI antibiotics use decreased, but the decrease was not commensurate with CDI rates following reflex testing. PCR+/GDH+/toxin+ samples had a lower mean Ct value than PCR+/GDH-/toxin- samples (23.3 vs 33.5, P < .0001). A Ct value of 28.65 could distinguish between those 2 groups. Fifty-four percent of PCR+/GDH+/toxin- samples had a Ct value below that cut-off, suggesting the possibility of CDI with a negative toxin test.
UNASSIGNED: Reflex testing for a laboratory diagnosis of CDI results in rapid, systemwide decreases in the rate of HO-CDI. Additional research is needed to distinguish CDI from C difficile colonization in patients with discordant testing.
摘要：
■推荐多步骤实验室检测用于诊断艰难梭菌感染（CDI）。这项研究的目的是介绍多步CDI诊断测试在学术医院系统中的影响，并评估PCR阳性测试的毒素B基因聚合酶链反应（PCR）循环阈值（Ct）值。
■2022年10月，我们的系统开始使用C.DIFFQUIKCHEKCOMPLETE（Techlab）对所有PCR阳性粪便样本进行反射测试，基于酶免疫测定的测试，其结果是谷氨酸脱氢酶抗原（GDH）和艰难梭菌毒素A/B。跟踪测试前后的医院发病（HO）CDI和CDI抗生素使用情况。从传染病诊断实验室获得Ct值。接收器操作曲线分析用于检查在各种Ct阈值下鉴定GDH+/毒素+和GDH-/毒素-的灵敏度和特异性。
■反射测试后，HO-CDI率从每1000个患者天0.352例下降到每1000个患者天0.115例（P<.005）。抗CDI抗生素使用减少，但这种下降与反射测试后的CDI率不相称.PCR+/GDH+/毒素+样品具有比PCR+/GDH-/毒素-样品更低的平均Ct值(23.3对33.5,P<0.0001)。28.65的Ct值可以区分这两组。54%的PCR+/GDH+/毒素-样品的Ct值低于该临界值，表明CDI与阴性毒素测试的可能性。
■用于CDI实验室诊断的反射检测可快速、全系统HO-CDI率下降。需要进一步的研究来区分CDI和艰难梭菌定植在不一致测试的患者中。
■2022年10月，我们的系统开始使用C.DIFFQUIKCHEKCOMPLETE（Techlab）对所有PCR阳性粪便样本进行反射测试，基于酶免疫测定的测试，其结果是谷氨酸脱氢酶抗原（GDH）和艰难梭菌毒素A/B。跟踪测试前后的医院发病（HO）CDI和CDI抗生素使用情况。从传染病诊断实验室获得Ct值。接收器操作曲线分析用于检查在各种Ct阈值下鉴定GDH+/毒素+和GDH-/毒素-的灵敏度和特异性。
■反射测试后，HO-CDI率从每1000个患者天0.352例下降到每1000个患者天0.115例（P<.005）。抗CDI抗生素使用减少，但这种下降与反射测试后的CDI率不相称.PCR+/GDH+/毒素+样品具有比PCR+/GDH-/毒素-样品更低的平均Ct值(23.3对33.5,P<0.0001)。28.65的Ct值可以区分这两组。54%的PCR+/GDH+/毒素-样品的Ct值低于该临界值，表明CDI与阴性毒素测试的可能性。
■用于CDI实验室诊断的反射检测可快速、全系统HO-CDI率下降。需要进一步的研究来区分CDI和艰难梭菌定植在不一致测试的患者中。
