Polymyxins are becoming an added value for treating infections due to multidrug-resistant Pseudomonas aeruginosa. Therefore, the Rapid Polymyxin/Pseudomonas NP test was developed for the identification of polymyxin resistance in P. aeruginosa isolates. This test detects the bacterial growth in a medium containing a defined concentration of colistin. Formation of basic metabolites is visually detected by yellow to purple/violet color change of the bromocresol purple pH indicator. The test performance was evaluated by using 50 colistin-resistant and colistin-susceptible P. aeruginosa isolates, among which 10 were colistin resistant. The sensitivity and specificity of the test were found to be 100% (CI95 65.5–100%) and 95% (CI95 81.8–99.1%), respectively, by comparison with broth microdilution as the reference method. The Rapid Polymyxin/Pseudomonas NP test is easy to perform, specific and sensitive, allowing rapid visual observation of results without the requirement any special reading equipment, and results are obtained in 3 h.

多粘菌素正成为治疗因多药耐药的铜绿假单胞菌引起的感染的附加值。因此，开发了快速多粘菌素/假单胞菌NP试验来鉴定铜绿假单胞菌分离株的多粘菌素抗性。该测试检测细菌在含有确定浓度的粘菌素的培养基中的生长。通过溴甲酚紫色pH指示剂的黄色到紫色/紫色颜色变化，目视检测到碱性代谢物的形成。通过使用50种对大肠菌素耐药和对大肠菌素敏感的铜绿假单胞菌来评估测试性能分离株，其中10株对大肠菌素具有抗性。与作为参考方法的肉汤微量稀释法相比，该试验的灵敏度和特异性分别为100％（CI95 65.5–100％）和95％（CI95 81.8–99.1％）。快速多粘菌素/假单胞菌NP测试易于执行，特异且灵敏，无需任何特殊阅读设备即可快速目视观察结果，并在3小时内获得结果。