Armed Forces Institute of Pathology, Rawalpindi, Pakistan.
Pakistan Navy Ship Shifa Hospital, Karachi, Pakistan.
J Ayub Med Coll Abbottabad. 2021 Oct-Dec;33(4):668-672.
Emergence of resistance among Escherichia coli (E.coli) isolates against therapeutic options for UTIs (Urinary tract infections) has led to renewed interest in older antibiotics like Fosfomycin. In this study we evaluated diagnostic accuracy of Rapid Fosfomycin NP test based on glucose metabolism for rapid Fosfomycin susceptibility testing among urinary E.coli isolates.
In a cross-sectional validation study conducted in the Microbiology Department, Armed Forces Institute of Pathology, Rawalpindi, Pakistan from 15th March to 15th September 2020, 149 consecutive urine specimens were included as per selection criteria. Rapid Fosfomycin NP test was performed as per protocol of Nordmann P et al on urinary E.coli isolates for detection of Fosfomycin resistance and results were compared with reference modified Kirby-Bauer disk diffusion method.
Out of total 149 E.coli isolates from 149 urine specimens, 80 were classified as Fosfomycin susceptible and 69 as Fosfomycin resistant by reference disk diffusion method. Sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of rapid Fosfomycin NP test was found to be 94.2%, 98.75%, 98.48%, 95.2% and 96.64%, respectively. In our study reliable results were achieved after 2.5 hours of incubation.
The rapid Fosfomycin NP test is valid and user-friendly technique which can be performed with minimal technical expertise. It is less time consuming than disk diffusion and Etest strips and easy to perform as compared to agar dilution method. It can be useful as alternative to agar dilution in urinary E.coli isolates which would help in selecting appropriate therapeutic option for UTIs.
大肠杆菌（E.coli）分离株对尿路感染（UTIs）治疗选择的耐药性的出现，导致人们对福沙霉素等较老的抗生素重新产生兴趣。在这项研究中，我们评估了基于葡萄糖代谢的快速福沙霉素 NP 试验在快速福沙霉素药敏试验中的诊断准确性，用于检测尿液中大肠杆菌的分离株。
在 2020 年 3 月 15 日至 9 月 15 日期间，在巴基斯坦拉瓦尔品第武装部队病理学研究所的微生物学系进行了一项横断面验证研究，根据选择标准纳入了 149 份连续的尿液标本。按照 Nordmann P 等人的方案对尿液中的大肠杆菌分离株进行快速福沙霉素 NP 试验，以检测福沙霉素耐药性，并将结果与参考改良 Kirby-Bauer 纸片扩散法进行比较。
在 149 份尿液标本中的 149 株大肠杆菌分离株中，有 80 株被参考纸片扩散法分类为福沙霉素敏感，69 株为福沙霉素耐药。快速福沙霉素 NP 试验的敏感性、特异性、阳性预测值、阴性预测值和诊断准确性分别为 94.2%、98.75%、98.48%、95.2%和 96.64%。在我们的研究中，经过 2.5 小时的孵育后，结果可靠。
快速福沙霉素 NP 试验是一种有效且易于使用的技术，只需最少的技术专长即可进行。它比纸片扩散法和 Etest 条耗时更少，而且比琼脂稀释法更容易操作。它可以作为尿液大肠杆菌分离株琼脂稀释法的替代方法，有助于选择合适的尿路感染治疗选择。
