Pandey Mragnayani, Xess Immaculata, Sachdev Janya, Sharad Neha, Gupta Sonakshi, Singh Gagandeep, Yadav Renu Kumari, Rana Bhaskar, Raj Stephen, Ahmad M Nizam, Nityadarshini Neha, Baitha Upendra, Soneja Manish, Prakash Bindu, Sikka Kapil, Mathur Purva, Jyotsna Viveka P, Kumar Rakesh, Wig Naveet, Gourav Sudesh, Biswas Ashutosh, Thakar Alok
Department of Microbiology, All India Institute of Medical Sciences, New Delhi 110029, India.
Department of Microbiology, All India Institute of Medical Sciences, New Delhi 110029, India.
J Infect. 2024 May;88(5):106147. doi: 10.1016/j.jinf.2024.106147. Epub 2024 Mar 28.
Invasive mould infections (IMIs) are a leading cause of death in patients with compromised immune systems. Proven invasive mould infection requires detection of a fungus by histopathological analysis of a biopsied specimen, sterile culture, or fungal DNA amplification by PCR in tissue. However, the clinical performance of a PCR assay on blood samples taken from patients suspected of invasive mould disease has not been fully evaluated, particularly for the differential diagnosis of invasive aspergillosis (IA) and invasive Mucormycosis (IM).
To assess the diagnostic utility of our previously validated in-house real-time PCR in blood samples for diagnosis of invasive aspergillosis and mucormycosis in patients with suspected invasive mould infection.
All patients with suspected invasive mould infection were prospectively enrolled from May 2021 to July 2021. Conventional fungal diagnosis was performed using tissue and respiratory samples. In-house PCR was performed on blood samples and its diagnostic performance evaluated.
A total of 158 cases of suspected invasive mould infection were enrolled in the study. The sensitivity and specificity of in-house PCR performed on blood samples was found to be 92.5% and 81.4% respectively for diagnosis of probable IA, and 65% and 84.62% respectively for diagnosis of proven and probable IM. It was also able to detect 3 out of 5 cases of possible IM where no other microbiological evidence of IM was obtained.
This assay could be helpful in minimally invasive diagnosis of IMIs for patients in whom invasive sampling is not feasible, especially as a preliminary or screening test. It can help in early diagnosis, anticipating conventional laboratory confirmation by days or weeks. Possible correlation between fungal load and mortality can help in initiating aggressive treatment for patients with high initial fungal load.
侵袭性霉菌感染（IMIs）是免疫系统受损患者死亡的主要原因。确诊侵袭性霉菌感染需要通过活检标本的组织病理学分析、无菌培养或组织中PCR真菌DNA扩增来检测真菌。然而，对疑似侵袭性霉菌病患者采集的血样进行PCR检测的临床性能尚未得到充分评估，尤其是在侵袭性曲霉病（IA）和侵袭性毛霉病（IM）的鉴别诊断方面。
评估我们之前验证的内部实时PCR在血样中对疑似侵袭性霉菌感染患者诊断侵袭性曲霉病和毛霉病的诊断效用。
2021年5月至2021年7月前瞻性纳入所有疑似侵袭性霉菌感染的患者。使用组织和呼吸道样本进行传统真菌诊断。对血样进行内部PCR并评估其诊断性能。
本研究共纳入158例疑似侵袭性霉菌感染病例。对血样进行的内部PCR诊断可能IA的敏感性和特异性分别为92.5%和81.4%，诊断确诊和可能IM的敏感性和特异性分别为65%和84.62%。它还能够检测出5例可能的IM中的3例，这些病例未获得其他IM的微生物学证据。
该检测方法对于无法进行侵入性采样的患者的IMIs微创诊断可能有帮助，尤其是作为初步或筛查试验。它有助于早期诊断，比传统实验室确认提前数天或数周。真菌载量与死亡率之间的可能关联有助于对初始真菌载量高的患者启动积极治疗。
