Department of Microbiology, Armed Forces Institute of Pathology (AFIP), Rawalpindi, Pakistan.
J Coll Physicians Surg Pak. 2022 Feb;32(2):177-180. doi: 10.29271/jcpsp.2022.02.177.
To determine the diagnostic accuracy of CHROMagarTM COL-APSE, for detection of colistin resistance in clinical isolates of multi drug resistant (MDR) gram negative bacilli (GNB).
Cross-sectional validation study.
Department of Microbiology, Armed Forces Institute of Pathology (AFIP), Rawalpindi, Pakistan from February 2019 to August 2019.
Total 96 MDR-GNB in clinical isolates were included. Isolates were identified using gram stain, catalase, oxidase, API 20E and API 20NE. After taking approval from Institutional Ethical Review Committee, colistin susceptibility was determined simultaneously by CHROMagarTM COL-APSE (using 1x105 CFU/ml inoculum) and Broth Micro Dilution (BMD) Minimum Inhibitory Concentration (MIC) method as per CLSI. EUCAST guidelines were followed for interpretation of susceptibility profile. Results were validated with gold standard test, i.e. BMD.
Out of 96 MDR clinical isolates, the distribution was K. pneumoniae n=63, E. coli n=18, A. baumannii n=11, C. freundii n=3, and E. cloacae n=1. The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of CHROMagarTM COL-APSE for detection of colistin resistance, keeping BMD-MIC method as gold standard, was 97.96%, 97.87%, 97.96%, 97.87% and 97.92%, respectively.
CHROMagarTM COL-APSE can be used as screening agar by direct streaking of specimen as well as diagnostic for detection of colistin resistance by the use of standardised inoculum. It can be used as a critical time saving method for colistin resistance detection in absence of expertise or manpower required for BMD as well as the cost required for genetic sequencing to detect MCR genes. Key Words: Multi drug resistant (MDR), Gram negative bacilli (GNB), Colistin resistance, CHROMagarTM COL-APSE.
确定 CHROMagarTM COL-APSE 在检测多药耐药（MDR）革兰氏阴性杆菌（GNB）临床分离株中对粘菌素耐药的诊断准确性。
横断面验证研究。
巴基斯坦拉瓦尔品第武装部队病理学研究所（AFIP）微生物学系，2019 年 2 月至 2019 年 8 月。
纳入 96 株临床分离的 MDR-GNB。使用革兰氏染色、触酶、氧化酶、API 20E 和 API 20NE 对分离物进行鉴定。在获得机构伦理审查委员会批准后，同时使用 CHROMagarTM COL-APSE（使用 1x105 CFU/ml 接种物）和肉汤微量稀释（BMD）最低抑菌浓度（MIC）方法，根据 CLSI 确定粘菌素药敏性。遵循 EUCAST 指南解释药敏谱。结果用金标准试验，即 BMD 进行验证。
96 株 MDR 临床分离株中，分布为肺炎克雷伯菌 n=63、大肠埃希菌 n=18、鲍曼不动杆菌 n=11、弗劳地柠檬酸杆菌 n=3、阴沟肠杆菌 n=1。以 BMD-MIC 法为金标准，CHROMagarTM COL-APSE 检测粘菌素耐药的敏感性、特异性、阳性预测值、阴性预测值和诊断准确性分别为 97.96%、97.87%、97.96%、97.87%和 97.92%。
CHROMagarTM COL-APSE 可用于直接划线标本的筛选琼脂，也可用于标准化接种物检测粘菌素耐药的诊断。它可以作为一种节省时间的方法，用于在缺乏 BMD 所需的专业知识或人力以及检测 MCR 基因所需的遗传测序成本的情况下检测粘菌素耐药。关键词：多药耐药（MDR）、革兰氏阴性杆菌（GNB）、粘菌素耐药、CHROMagarTM COL-APSE。
