尿路感染是由细菌(极少数可由厌氧菌、真菌、原虫、病毒引起)直接侵袭泌尿系统所引起的感染性疾病,根据感染发生部位可分为上尿路感染、下尿路感染;上尿路感染是指肾盂肾炎,下尿路感染包括膀胱炎和尿道炎。社区获得性尿路感染的病原菌约80%～90%是大肠埃希菌[1];医院内尿路感染的常见病原菌除了大肠埃希菌,还有变形杆菌、克雷伯 Urinary tract infections are infectious diseases caused by direct invasion of the urinary system by bacteria (very few can be caused by anaerobic bacteria, fungi, protozoa and viruses). According to the infection site, they can be classified as upper urinary tract infection and lower urinary tract infection. Urinary tract infection refers to pyelonephritis, lower urinary tract infections include cystitis and urethritis. About 80% to 90% of community-acquired urinary tract infections are Escherichia coli [1]; common pathogens in urinary tract infections in hospitals include Escherichia coli, Proteus, Kleber