侵袭性真菌感染诊断的三种方法研究

Study of three different methods in diagnosis of invasive fungal infections

目的:评估血浆(1-3)-β-D-葡聚糖检测(G实验)、真菌培养法及直接涂片法在侵袭性真菌感染诊断中的方法比较。方法:通过112例怀疑侵袭性真菌感染住院患者在其发热当天抽静脉血做G实验检测,同时留取血液、呼吸道、泌尿道或肠道标本做真菌培养及涂片法检真菌。结果:回顾性分析以血液病/恶性肿瘤患者侵袭性真菌感染的诊断标准与治疗原则(草案)作为临床诊断标准,并以此为标准比较G实验﹑真菌培养及直接涂片法结果,分别计算三种方法及联合检测的灵敏度、特异度、阳性和阴性预测值。G实验、真菌培养法、直接涂片法及三者联合检测的灵敏度、特异度、阳性和阴性预测值分别为86.44%、83.02%、85.00%和84.61%;83.05%、84.91%、85.96%和81.82%;61.02%、94.12%、87.80%和67.61%;91.53%%、81.13%、84.38%和89.58%。结论:G实验﹑真菌培养法及直接涂片法相比较各有优缺点,G实验的灵敏度和阴性预测值高,直接涂片法的特异度高。如果联合检测既可具有G实验的优点,又具有直接涂片法及真菌培养法的优点,减少假阴性,为临床提供直接的诊断依据,对早期诊断侵袭性真菌感染更具临床意义。

Objective：To study and compare the clinical significance of plasma （1-3） -β-D-glycan （G-test）, fungal cul-ture, fungal smear in diagnosis of invasive fungal infections （IFI）. Methods：112 inpatients with suspected invasive fungal infection were collected. Their venous blood was sampled on the day of fever for the G-test, and then their blood, respiratory tract, urinary tract or intestinal tract samples were collected for the fungal culture and fungal smear at the same time. Results： The retrospective analysis used the diagnostic criteria and therapeutic principle （protocol） of the invasive fungal infections for the patients with hematologic disea-ses / malignant tumors as the clinical diagnostic criteria. By using the above criteria, the results of the three methods were compared and their sensitivity, specificity, and the positive and negative predictive values were calculated, respectively. The sensitivity, speci-ficity, and the positive and negative predictive values of G-test, fungal culture, fungal smear, G-test combined with fungal culture and fungal smear were 86. 44% ,83. 02% ,85. 00% and 84. 61% ;83. 05% ,84. 91% ,85. 96% and 81. 82% ;61. 02% ,94. 12% ,87. 80%and 67. 61% ; 91. 53% 、81. 13% , 84. 38% and 89. 58% . Conclusions： G-test, fungal culture, and fungal smear all have advantages and disadvantages. The performance of G-test appears to be better in the sensitivity and negative predictive value. Fungal smear has a higher specificity. G-test combined with fungal culture and fungal smear has all the advantages of the three methods, decreases false negative cases, can offer a direct diagnostic basis for the clinic,and has a great significance in the early diagnosis of invasive fungal in-fections.