Gourav Sudesh, Singh Gagandeep, Kashyap Lokesh, Rana Bhaskar, Raj Swet, Xess Immaculata
Department of Microbiology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi-110029, India.
Department of Anesthesiology, Pain Medicine & Critical Care, All India Institute of Medical Sciences, Ansari Nagar, New Delhi-110029, India.
Curr Med Mycol. 2024 May 10;10. doi: 10.22034/cmm.2024.345199.1513. eCollection 2024.
Invasive candidiasis (IC) in the hospitalized population is one of the leading causes of invasive fungal infections (IFIs). Microbiological diagnosis of IC suffers due to poor sensitivity of blood culture and relative inaccessibility to more sensitive modalities. (1, 3)-β-D-glucan (BDG) is a cell wall polysaccharide found in a range of fungi. Various commercial assays are available based on various detection techniques. This study aimed to assess the diagnostic performance of the FungiXpert® Fungus BDG Detection Kit by Genobio Pharmaceutical Co. Ltd. (Tianjin, China), based on chemiluminescent method, for diagnosis of candidemia and deep-seated candidiasis.
In total, 80 patients (34 males and 46 females) were included with a median age of 35 years old. In accordance with EORTC/MSGERC definitions, 39 patients had proven IC. The number of patients within the probable, possible, and no IC (taken as control) groups were 8, 4, and 29, respectively. Blood samples were collected for fungal blood culture and BDG assay.
After exclusion of cases with evidence of concurrent IFI other than IC, median serum BDG was 0.63 ng/ml for proven IC; while it was 0.04 ng/ml for NO IC. Sensitivity, specificity, positive, and negative predictive values were 60.52%, 81.81%, 85.18%, and 54.54%, respectively. Positive likelihood ratio was 3.32. While the assay performed best for with median BDG of 1.92 ng/ml and sensitivity of 92.3%, its performance was worst for , with median BDG of 0.04 ng/ml and sensitivity of 44.44%. Overall mortality rate was 65.62% in the BDG positive group, which was significantly higher than that in the BDG negative group (33.33%).
The performance of the FungiXpert® Fungus BDG Detection Kit was acceptable for invasive candidiasis in the present resource-limited setup. The major advantages of this assay were the ease of performance in a semi-automated cartridge format, relatively lower cost per test, non-reliance on glucan-free procedures or instruments and minimal hands-on procedure.
住院患者侵袭性念珠菌病（IC）是侵袭性真菌感染（IFI）的主要原因之一。由于血培养敏感性差以及更敏感检测方法相对难以获取，IC的微生物学诊断受到影响。（1,3）-β-D-葡聚糖（BDG）是一种存在于多种真菌中的细胞壁多糖。基于各种检测技术有多种商业检测方法。本研究旨在评估天津金匙医学科技有限公司的FungiXpert®真菌BDG检测试剂盒基于化学发光法对念珠菌血症和深部念珠菌病的诊断性能。
共纳入80例患者（男性34例，女性46例），中位年龄35岁。根据欧洲癌症研究与治疗组织/美国国立过敏与传染病研究所真菌病研究合作组（EORTC/MSGERC）的定义，39例患者确诊为IC。疑似、可能和非IC（作为对照组）组的患者人数分别为8例、4例和29例。采集血样进行真菌血培养和BDG检测。
排除除IC外有IFI并发证据的病例后，确诊IC患者的血清BDG中位数为0.63 ng/ml；非IC患者为0.04 ng/ml。敏感性、特异性、阳性预测值和阴性预测值分别为60.52%、81.81%、85.18%和54.54%。阳性似然比为3.32。该检测方法对BDG中位数为1.92 ng/ml且敏感性为92.3%的情况表现最佳，而对BDG中位数为0.04 ng/ml且敏感性为44.44%的情况表现最差。BDG阳性组的总死亡率为65.62%，显著高于BDG阴性组（33.33%）。
在目前资源有限的情况下，FungiXpert®真菌BDG检测试剂盒对侵袭性念珠菌病的检测性能是可接受的。该检测方法的主要优点是以半自动试剂盒形式操作简便、每次检测成本相对较低、不依赖无葡聚糖的程序或仪器且实际操作最少。
