Department of Medical Microbiology and Infectious Diseases, Canisius Wilhelmina Hospital, Nijmegen, Netherlands.
Department of Medical Mycology, Westerdijk Fungal Biodiversity Institute, Utrecht, Netherlands.
Front Cell Infect Microbiol. 2018 Oct 23;8:377. doi: 10.3389/fcimb.2018.00377. eCollection 2018.
Invasive aspergillosis (IA) is a deep tissue infection with a high mortality occurring mostly in immunocompromised patients. To investigate the pathology of patients with IA it may be important to determine the genotype of the invasive isolate of , however available tissues for study are often formalin fixed paraffin embedded (FFPE). Although DNA has been successfully isolated from such tissues for species identification, genotyping of species on such tissues has not yet been performed. In this study we aimed to determine the genotype of in FFPE tissue and serum samples from five patients with invasive aspergillosis using nine highly polymorphic short tandem repeat (STR) loci. FFPE lung and bronchial biopsies from all patients were successfully typed. By comparing the latter result with non-FFPE materials from non-sterile samples such as sputum, bronchoalveolar lavage and lung abscess, we found identical genotypes within three patients, while the two other patients had a dominant genotype shared among all sample types. Genotyping of serum samples was successful in two serum samples with galactomannan ratios of 4 and 5.6, but failed in serum samples with galactomannan levels <0.5. In addition, testing a subset of these materials with the AsperGenius multiplex qPCR assay, we did not find azole resistance mutations. With this STR assay, from FFPE tissue and serum was successfully genotyped, allowing retrospective examination of in culture negative patients with IA.
侵袭性曲霉菌病（IA）是一种深部组织感染，死亡率很高，主要发生在免疫功能低下的患者中。为了研究 IA 患者的病理学，确定侵袭性分离株的基因型可能很重要，然而，可供研究的组织通常是福尔马林固定石蜡包埋（FFPE）的。尽管已经成功地从这些组织中分离出 DNA 用于物种鉴定，但尚未对这些组织中的 种进行基因分型。在这项研究中，我们旨在使用 9 个高度多态性短串联重复（STR）基因座，确定来自 5 名侵袭性曲霉菌病患者的 FFPE 组织和血清样本中的基因型。所有患者的 FFPE 肺和支气管活检均成功进行了分型。通过将后者的结果与非无菌样本（如痰、支气管肺泡灌洗液和肺脓肿）的非 FFPE 材料进行比较，我们发现 3 名患者的基因型相同，而另外 2 名患者的基因型在所有样本类型中均占主导地位。在 2 份血清样本中，Galactomannan 比值分别为 4 和 5.6，血清样本的基因分型成功，Galactomannan 水平<0.5 的血清样本则不成功。此外，用 AsperGenius 多重 qPCR 检测了这些材料的一部分，我们没有发现唑类耐药突变。使用这种 STR 检测方法，成功地对 FFPE 组织和血清中的 进行了基因分型，允许对 IA 培养阴性患者进行回顾性检查。
