Mancini Nicasio, Clerici Daniela, Diotti Roberta, Perotti Mario, Ghidoli Nadia, De Marco Donata, Pizzorno Beatrice, Emrich Thomas, Burioni Roberto, Ciceri Fabio, Clementi Massimo
Laboratorio di Microbiologia e Virologia, Università 'Vita-Salute' San Raffaele, Milano, Italy.
Unità di Ematologia e Trapianto di Midollo Osseo, Istituto Scientifico San Raffaele, Milano, Italy.
J Med Microbiol. 2008 May;57(Pt 5):601-604. doi: 10.1099/jmm.0.47732-0.
The rapid diagnosis of an infectious cause in the course of fever of unknown origin plays a pivotal role in the correct management of neutropenic patients. In this study, blood samples from febrile oncohaematological patients were tested using a novel commercial real-time PCR assay (LightCycler SeptiFast; Roche Molecular Systems) and blood culture (BacT/Alert 3D; bioMérieux). Twenty-one (20.4 %) and 34 (33 %) of the 103 samples under study tested positive by blood culture and PCR, respectively. The analysis of concordance evidenced a low correlation between the two approaches (83 %), mainly due to samples that tested negative by culture but positive using the molecular approach. Among 14 discordant cases negative by culture but positive by PCR, 12 were observed in sequential samples of patients with initial concordant results on samples drawn before the administration of a specific antimicrobial therapy. Moreover, DNA of a fastidious organism, Aspergillus fumigatus, not easily detectable by the cultural approach was rapidly detected in the two remaining discordant cases. Overall, the characteristics featured by the molecular method could be of interest in the development of new algorithms for the diagnosis of sepsis in critical patients.
不明原因发热过程中感染病因的快速诊断在中性粒细胞减少患者的正确管理中起着关键作用。在本研究中，使用一种新型商业实时聚合酶链反应检测法（LightCycler SeptiFast；罗氏分子系统公司）和血培养（BacT/Alert 3D；生物梅里埃公司）对发热的肿瘤血液学患者的血样进行检测。在所研究的103份样本中，分别有21份（20.4%）和34份（33%）通过血培养和聚合酶链反应检测呈阳性。一致性分析表明两种方法之间的相关性较低（83%），主要是由于一些样本培养结果为阴性但分子检测方法结果为阳性。在14例培养阴性但聚合酶链反应阳性的不一致病例中，有12例出现在接受特定抗菌治疗前采集的样本最初结果一致的患者的连续样本中。此外，在其余两例不一致病例中快速检测到一种难以通过培养方法检测到的苛养菌——烟曲霉的DNA。总体而言，分子方法的特点可能对开发危重症患者败血症诊断的新算法具有重要意义。
