血清半乳甘露聚糖、(1,3)-β-D葡聚糖和真菌核酸检测对侵袭性真菌感染的早期诊断价值研究

Clinical significance of detection of serum galactomannan,(1,3)-β-D-glucan and fungal nucleic acid in the early diagnosis of invasive fungal infections

目的研究血清半乳甘露聚糖(galactomannan,GM)、(1,3)-β-D-葡聚糖(1,3 beta-D-glucan,BG)和真菌核酸检测对血液病和恶性肿瘤患者侵袭性真菌感染(invasive fungal infections,IFI)的诊断价值,为临床及时合理用药提供依据。方法将256例血液病和恶性肿瘤患者纳入实验研究,每周两次同时采集患者血清和血浆,实际共收集3272份标本。采用ELISA Platelia Aspergillus试剂盒检测血清中的GM,以0.8为阳性界值。采用MB-80微生物快速检测系统检测BG含量,以20pg/ml为阳性界值。以曲霉为研究对象,建立了Real-time PCR检测真菌的技术平台。对所有血清标本进行GM、BG和真菌核酸检测,分别研究和对比三种诊断试验的评价指标及其在抗真菌治疗中的应用价值。结果以GM阳性为起点对真菌感染高危患者给予伏立康唑、伊曲康唑等抗曲霉抢先治疗,病死率可减少至7.8%(5/64)。GM水平可随着IA病情的进展而增加,也可随着抗真菌治疗有效而下降,并与预后密切相关。三种方法联合检测对IA的敏感性为73.3%(33/45),特异性100.0%(62/62),PPV为100.0%(33/33),NPV为83.8%(62/74)。临床诊断IA时结合GM、BG和PCR检测结果指导抗真菌治疗,三种方法检测均阴性的45例患者可以不接受抗真菌治疗,减少了23.2%(45/194)的经验性抗真菌治疗,避免了由其引起的药物费用和药物毒性作用。结论血清半乳甘露聚糖、(1,3)-β-D葡聚糖和真菌核酸检测诊断技术对IA感染有较好的早期诊断价值。但三种方法单独用于IFI的诊断均存在一定假阳性问题,三者联合检测可提高检测的特异性和阳性预测值,在一定程度上弥补了各方法的不足,减少了假阳性和假阴性结果,对早期诊断IFI和抗真菌治疗方面有指导意义。若三种方法同时阳性高度提示IA的临床诊断,三种方法均阴性有助于排除IA感染,减少过度抗真菌治疗和药物毒性。

Objective To investigate the clinical significance of galactomannan(GM),(1,3)-β-D-glucan(BG) andfungal nucleic acid detection in the diagnosis of invasive fungal infection(IFI) in patients with hematologic malignancies and malignant tumors.Methods 3272 of systematically collected serum and plasma samples obtained from 256 patients at high-risk of IFI were detected with platelia Aspergillus assay kit and MB-80 microorganism rapid detection system.Taking the Aspergillus as the research object,the method for rapid detection of Aspergillus technology platform was developed using quantitative PCR.According to results of GM,BG and fungal nucleic acid detection for 256 patients with hematologic malignancies and malignant tumors,the sensitivity,specificity,positive predictive value(PPV),negative predictive value(NPV)of GM,BG and fungal nucleic acid detection were analyzed.Results The mortality can be reduced to 7.8%(5/64) when the preemptive antifungal therapy of voriconazole or itraconazole were administrated according to positive results of GM.The over-treatment and drug toxicity can be avoided.Combined detection of the three methods for the diagnosis of IA has shown sensitivity,specificity,PPV and NPV values of 73.3%(33/45),100.0%(62/62),100.0%(33/33),83.8%(62/74),respectively.Conclusion Combined detection of three methods can improve the specificity and positive predictive value of detection.The detection of BG have shown high sensitive for screening IFI patients.BG detection can be used as diagnostic screening IFI.There were the high specificity for fungal nucleic acid and GM detection in the diagnosis of IA.If the three methods were positive at the same time,IA will be highly suggestive of clinical infection.If the three methods were negative,IFI can be excluded from clinical infections.