血浆(1,3)-β-D葡聚糖检测对血液病患者侵袭性真菌感染的诊断价值

Diagnostic Value of Plasma (1,3)-β-D Glucan Assay for Invasive Fungal Infections in Patients with Hematological Disorders

免疫功能低下患者的侵袭性真菌感染(IFI)具有病死率高,诊断困难等特点。针对真菌病原的血清学方法如(1,3)-β-D葡聚糖(BG)检测(G试验)、曲霉半乳甘露聚糖检测(GM试验)具有操作简单、快速、敏感性相对高等特点,可做为IFI诊断的辅助手段。较GM试验比,G试验可用于诊断除曲霉菌外更多的真菌感染。本研究旨在探讨G试验在血液病患者IFI早期诊断中的价值。血浆标本来源于2007年5月-2008年5月来自北京道培医院162例疑为IFI的血液病患者,其中化疗后患者85例,造血干细胞移植后患者77例。应用MB-80微生物动态快速检测系统定量检测患者血浆中BG的含量,将检测结果及临床特征进行回顾性分析。按照欧洲癌症研究治疗组织及真菌研究组(EORTC/MSG)诊断标准,所有病例中有确定诊断2例,临床诊断18例,拟诊75例,排除诊断67例。结果表明:以20ng/ml为诊断界值,G试验的敏感性、特异性、阳性预测值(PPV)和阴性预测值(NPV)分别为75%、91%、72.4%和92.4%。在75例拟诊病例中,其中有51例G试验阳性,且对广谱抗生素无效而经过抗真菌治疗有效,经过临床回顾性分析符合IFI,表明G试验使IFI诊断率提高31.4%。结论:G试验是早期诊断血液病患者IFI的简单、快速的方法。

The invasive fungal infections （IFI） in immunocompromised patients are associated with a high mortality rate and diagnostic difficulty. Serological methods such as aspergillus galactomannan assay （GM test） and （1,3）-β-D glucan （BG） assay （G test ） can be used as an adjunctive method for IFI diagnosis based on their characteristics of easyoperating, rapidness and high sensitivity. Compared with GM test, G test can be more widely used except for the diagnosis of aspergillosis. The purpose of this study was to investigate the value of G test in the diagnosis of IFI in patients with hematological disorders. The plasma was collected from 162 suspected IFI patients with hematological disorders in Beijing Daopei Hospital, including 85 patients after chemotherapy and 77 patients after stem cell transplantation from May 2007 to May 2008, BG level was measured with MB-80 Microbiology Kinetic Rapid Reader and the measured results together with the clinical characteristics were retrospectively analyzed. According to the European Organization for Research and Treatment of Cancer/Mycoses Study Group （EORTC/MSG） criteria, there were 2 patients diagnosed as proven IFI, 18 as probable IFI, 75 as possible IFI and 67 as no IFI. The results showed that at a cutoff of 20 pg/ml, the sensitivity and specificity of G test were 75% and 91% respectively, with a positive predictive value （PPV） of 71.4% and a negative predictive value （NPV） of 92.4%. 51 out of the 75 possible IFI patients with elevated BG level were responsive to antifugal treatment but non responsive to broad-spectrum antibiotics, retrospectively were diagnosed as IFI, suggesting that G test improved the IFI diagnostic rate by 31.4%. In conclusion, G test is a rapid and simple method for early diagnosis of IFI in patients with hematological disorders.