Eichinger Simone, Kikhney Judith, Moter Annette, Wießner Alexandra, Eichinger Walter B
Department of Cardiac Surgery, Hospital Bogenhausen, Munich, Germany.
Department of Microbiology, Infectious Diseases and Immunology, Biofilmcenter, Charité - University Medicine Berlin, Berlin, Germany.
Interact Cardiovasc Thorac Surg. 2019 Nov 1;29(5):678-684. doi: 10.1093/icvts/ivz159.
In infective endocarditis (IE), identification of the causative organism and consecutive treatment are crucial for patient survival. Although the macroscopic aspect resembles infected tissue, standard diagnostic tests often fail to allow one to identify bacteria. Fluorescence in situ hybridization (FISH) is a molecular, culture-independent technique that allows one to identify and visualize microorganisms within tissue and to recognize their morphology, number and activity. We analysed the diagnostic benefit of FISH/polymerase chain reaction (PCR) by comparing its results to those of standard diagnostic tests.
From September 2015 to April 2018, 128 patients underwent first-time or redo valve surgery to treat IE. Patients were designated according to the modified Duke criteria as definite (n = 61), possible (n = 34) or rejected (n = 33) IE. Tissue specimens obtained intraoperatively were analysed using FISH/PCR in addition to undergoing standard diagnostic testing and PCR alone.
We used blood cultures to detect microorganisms in 67/128 patients; valve cultures, in 34/128; PCR, in 67/128; histopathological diagnosis showed IE in 72/128 cases. We were able to detect microorganisms in 103/128 cases using FISH/PCR, with 55/61 in definite IE. Furthermore, we were able to identify 26 cases of bacterial biofilm using FISH/PCR, despite antibiotic treatment of 61 in the definite, 13 in the possible and 1 in the rejected group, including 8/33 patients in the rejected group with active bacteria. In all cases, the patient's therapy was altered.
FISH/PCR was used to identify microorganisms in cases in which standard diagnostic tests failed to provide sufficient results for various reasons. Furthermore, FISH/PCR enabled us to identify bacterial biofilms and to differentiate between active versus degraded bacteria, thus indicating the impact of treatment. Therefore, we suggest FISH/PCR as an additional diagnostic tool in IE alongside standard diagnostic tests.
在感染性心内膜炎（IE）中，确定病原体并进行后续治疗对患者生存至关重要。尽管宏观表现类似于感染组织，但标准诊断测试常常无法鉴定出细菌。荧光原位杂交（FISH）是一种独立于培养的分子技术，可用于在组织内鉴定和可视化微生物，并识别其形态、数量和活性。我们通过将FISH/聚合酶链反应（PCR）的结果与标准诊断测试的结果进行比较，分析了其诊断价值。
2015年9月至2018年4月，128例患者接受了首次或再次瓣膜手术以治疗IE。根据改良的杜克标准，患者被分为确诊（n = 61）、可能（n = 34）或排除（n = 33）IE。术中获取的组织标本除了进行标准诊断测试和单独的PCR外，还使用FISH/PCR进行分析。
我们使用血培养在67/128例患者中检测到微生物；瓣膜培养在34/128例中检测到；PCR在67/128例中检测到；组织病理学诊断显示72/128例为IE。使用FISH/PCR，我们在103/128例中检测到微生物，其中确诊IE中有55/61例。此外，尽管确诊组中有61例、可能组中有13例、排除组中有1例接受了抗生素治疗，包括排除组中8/33例有活性细菌的患者，但我们使用FISH/PCR仍能够鉴定出26例细菌生物膜。在所有病例中，患者的治疗方案均发生了改变。
FISH/PCR用于在标准诊断测试因各种原因未能提供足够结果的情况下鉴定微生物。此外，FISH/PCR使我们能够鉴定细菌生物膜，并区分活性细菌与退化细菌，从而显示治疗效果。因此，我们建议将FISH/PCR作为IE标准诊断测试之外的一种辅助诊断工具。
