侵袭性烟曲霉菌感染早期诊断的实验研究

目的：探讨巢式聚合酶链反应(PCR)方法和曲霉菌半乳甘露聚糖抗原酶联免疫吸附试验(ELISA)检测方法早期诊断侵袭性曲霉菌感染的可行性和临床应用价值。方法：(1)建立侵袭性曲霉菌感染的动物模型，收集不同时期实验动物的血样及各脏器标本，进行巢式PCR方法的检测。(2)对临床确诊或拟诊的侵袭性曲霉菌感染患者的血液标本进行巢式PCR方法的检测；对血清标本进行曲霉菌半乳甘露聚糖抗原nISA方法的检测。结果：(1)动物实验中，巢式PCR和血培养阳性率分别为77．8％和16．7％，两者差异具有显著意义；灵敏度和特异度分别为77．8％和：100％。(2)在临床确诊或拟诊的侵袭性曲霉菌感染患者的检测中巢式PCR方法的灵敏度和特异度分别为100％和83．3％；曲霉菌半乳甘露聚糖抗原ELISA检测的灵敏度和特异度分别为55．6％和88．2％。结论：巢式PCR方法具有良好的灵敏度和特异性，适用于临床早期诊断侵袭性曲霉菌感染。曲霉菌半乳甘露聚糖抗原ELISA检测可用于临床诊断侵袭性曲霉菌菌感染，有望辅助或替代传统方法。

The study on early diagnosis of invasive aspergillosis by the use of ELISA assay and nest PCR

Objective To develop a new specie-specific nest PCR to diagnose the invasive aspergillosis and to estimate the detection of circulating galactomannan by sandwich ELISA in immunocompromised patients. Methods (1) To develop an animal model of IA and collect the whole blood and tissues from the animal model. To extract the DNA from the whole blood and perform nest PCR of the DNA ;To perform the nest PCR of the clinical blood samples from immunocompromised patients (2)To detect the circulating galactomannan from the immunocompromised patients samples by use of sandwich ELISA. Results (1) In animal model, the positive rate of nest PCR and blood culture were 77.8% and 16.7%;The sensitivity and specificity of nest PCR in animal model with invasive aspergillosis are 77.8% and 100%;(2) The sensitivity and specificity of nest PCR in immunocompromised patient were 100% and 83.3%;The sensitivity and specificity of sandwich ELISA in immunocompromised patient were 55.6% and 88.2%. Conclusions The positive rate of the nest PCR was higher than that of the blood culture in animal model. The nest PCR method has good sensitivity and specificity in both animal model and patients. It will be a promising method in diagnosis of invasive aspergillosis. The ELISA method will be helpful in diagnosis of invasive aspergillosis.