Node J, Scherer E, Millon L, Bellanger A P
Department of Parasitology-Mycology, University Hospital of Besancon, Besancon, France.
Department of Parasitology-Mycology, University Hospital of Besancon, Besancon, France; Chrono-Environment Research Team UMR/CNRS-6249, University of Bourgogne Franche-Comté, Besançon, France.
J Mycol Med. 2024 Dec;34(4):101508. doi: 10.1016/j.mycmed.2024.101508. Epub 2024 Aug 28.
A commercial loop-mediated isothermal amplification (LAMP) assay is available for the detection of Pneumocytis jirovecii (Eazyplex®, Amplex diagnostics, Germany). Few centers currently use this LAMP assay in France. Recently, the commercialization of reagents used to perform the P. jirovecii immunofluorescence assay (IFA) was stopped. This study aimed to assess the position of the commercial LAMP P. jirovecii assay in the diagnostic strategy for Pneumocystis pneumonia. Over 24 months (August 1, 2021, to September 1, 2023), all bronchoalveolar lavage fluid (BALF) samples with a request for P. jirovecii detection were analyzed with the commercial Eazyplex® LAMP assay, using a Genie 2® device (Amplex, diagnostics), in parallel with the techniques used for direct examination. Specific P. jirovecii quantitative real-time PCR (qPCR) was subsequently performed. In total, 346 BALF samples were analyzed by Diff-Quik coloration, IFA, and the commercial Eazyplex® LAMP assay for initial screening. Twenty-six cases of PCP were retained based on radiological, biological and clinical criteria. Among the 26 cases of PCP, 11 BALF samples were positive using the initial screening techniques: four with the three techniques, six by IFA and Eazyplex®, and one only by IFA. The eleven BALF samples were positive with the specific P. jirovecii qPCR assay, with a mean quantification cycle (Cq) of 27 [19-32]. The commercial Eazyplex® LAMP assay is able to provide a result in 25 min and its sensitivity is similar to that of BALF direct examination techniques, such as IFA, which is a technique no longer available on the European market. The sensitivity of the commercial Eazyplex® LAMP assay is however clearly inferior to that of the specific P. jirovecii qPCR assay and, therefore, cannot replace the specific qPCR, but may have a place in the diagnostic strategy.
一种用于检测耶氏肺孢子菌的商业环介导等温扩增（LAMP）检测方法（Eazyplex®，Amplex诊断公司，德国）可供使用。目前在法国很少有中心使用这种LAMP检测方法。最近，用于进行耶氏肺孢子菌免疫荧光检测（IFA）的试剂停止商业化生产。本研究旨在评估商业LAMP耶氏肺孢子菌检测方法在肺孢子菌肺炎诊断策略中的地位。在24个月（2021年8月1日至2023年9月1日）期间，所有要求检测耶氏肺孢子菌的支气管肺泡灌洗液（BALF）样本，使用Genie 2®设备（Amplex诊断公司），采用商业Eazyplex® LAMP检测方法进行分析，并与直接检查所用技术并行进行。随后进行了耶氏肺孢子菌特异性定量实时PCR（qPCR）检测。总共346份BALF样本通过Diff - Quik染色、IFA和商业Eazyplex® LAMP检测方法进行初步筛查。根据放射学、生物学和临床标准，确定了26例肺孢子菌肺炎病例。在这26例肺孢子菌肺炎病例中，11份BALF样本在初始筛查技术中呈阳性：4份在三种技术中均呈阳性，6份通过IFA和Eazyplex®呈阳性，1份仅通过IFA呈阳性。这11份BALF样本在耶氏肺孢子菌特异性qPCR检测中呈阳性，平均定量循环（Cq）为27 [19 - 32]。商业Eazyplex® LAMP检测方法能够在25分钟内得出结果，其灵敏度与BALF直接检查技术（如IFA，欧洲市场上已不再有该技术）相似。然而，商业Eazyplex® LAMP检测方法的灵敏度明显低于耶氏肺孢子菌特异性qPCR检测方法，因此不能替代特异性qPCR，但可能在诊断策略中占有一席之地。
