Steinmann J, Giraud S, Schmidt D, Sedlacek L, Hamprecht A, Houbraken J, Meis J F, Bouchara J P, Buer J, Rath P-M
Institute of Medical Microbiology, University Hospital Essen, University of Duisburg-Essen Essen, Germany.
L'UNAM Université, Université d'Angers, Groupe d'Etude des Interactions Hôte-Pathogène Angers, France.
New Microbes New Infect. 2014 May;2(3):72-8. doi: 10.1002/nmi2.44. Epub 2014 Apr 20.
Members of the recently introduced fungal genus Rasamsonia (formerly included in the Geosmithia genus) have been described as emerging pathogens in immunosuppressed hosts or patients with cystic fibrosis (CF). Rasamsonia species have often been misidentified as Penicillium or Paecilomyces because of similar morphological characteristics. We validated a commercially available real-time PCR assay (Primerdesign™, UK) for accurate detection of species from the Rasamsonia argillacea complex. First, we tested this assay with a collection of 74 reference strains and clinical isolates and then compared the PCR with cultures of 234 respiratory samples from 152 patients with CF from two University Hospitals in Germany and France. The assay reliably detected the three main species within the Rasamsonia argillacea species complex (R. argillacea, R. piperina, R. aegroticola), which are typically encountered in CF patients. The limit of DNA detection was between 0.01 and 1 pg/μL. Analysis of the DNA extracts from respiratory specimens of CF patients revealed that four out of the 153 patients studied (2.6%) were colonized with R. argillacea species complex. Two species from the R. argillacea complex grew in the parallel cultures from the same patients. In one patient the PCR was positive 5 months before culture. The real-time PCR assay is a sensitive and specific method for detecting the three most important species of the R. argillacea species complex encountered in the CF context. Detection of these emerging pathogens in respiratory secretions from CF patients by this novel assay may increase our understanding of the occurrence and epidemiology of the R. argillacea species complex.
最近新提出的真菌属拉氏木霉属（Rasamsonia）（以前包含在土栖曲霉属（Geosmithia）中）的成员已被描述为免疫抑制宿主或囊性纤维化（CF）患者中的新兴病原体。由于形态特征相似，拉氏木霉属物种经常被误鉴定为青霉属（Penicillium）或拟青霉属（Paecilomyces）。我们验证了一种市售的实时荧光定量PCR检测方法（英国Primerdesign™公司），用于准确检测来自泥质拉氏木霉复合体（Rasamsonia argillacea complex）的物种。首先，我们用74株参考菌株和临床分离株对该检测方法进行了测试，然后将PCR结果与来自德国和法国两家大学医院的152例CF患者的234份呼吸道样本的培养结果进行了比较。该检测方法可靠地检测出了泥质拉氏木霉复合体中的三种主要物种（泥质拉氏木霉（R. argillacea）、胡椒拉氏木霉（R. piperina）、致病拉氏木霉（R. aegroticola）），这些物种在CF患者中较为常见。DNA检测限在0.01至1 pg/μL之间。对CF患者呼吸道标本的DNA提取物分析显示，在研究的153例患者中，有4例（2.6%）被泥质拉氏木霉复合体定殖。来自泥质拉氏木霉复合体的两个物种在同一患者的平行培养物中生长。在一名患者中，PCR检测在培养前5个月呈阳性。实时荧光定量PCR检测方法是一种灵敏且特异的方法，可用于检测在CF环境中遇到的泥质拉氏木霉复合体的三种最重要的物种。通过这种新检测方法在CF患者呼吸道分泌物中检测这些新兴病原体，可能会增加我们对泥质拉氏木霉复合体的发生情况和流行病学的了解。
