693株细菌的药物敏感试验及质粒分析

Plamsid analysis and antibiotic susceptibility testing of 693 strains of bacteria

目的研究６９３株细菌的药物敏感状况与其质粒的关系。方法用改良Ｂｉｒｎｂｏｉｍ法提取质粒，对１９８６～１９９０年６９３株细菌进行药敏试验。结果金黄色葡萄球菌的１．９Ｕ质粒带有１０种耐药基因，此耐药质粒在我院烧伤病室广泛传播；致病性大肠杆菌（ＥＰＥＣ）Ｏ１２７∶Ｈ６的６０Ｕ质粒带有３种耐药基因；鼠伤寒沙门菌的９８ｋｂ质粒带有５种。１９８６年庆大霉素、苯唑西林、红霉素、头孢噻肟对金黄色葡萄球菌均１００％敏感，但１９８９年已分别降至４８．１％、４６．９％、９．９％、７．４％，对阿米卡星仍有９７．５％敏感；阿米卡星对鼠伤寒沙门菌、ＥＰＥＣＯ１２７∶Ｈ６、绿脓杆菌的敏感率分别为９６．９％、９５．５％、９４．３％。结论阿米卡星适用于国内新生儿败血症的治疗。

Objective To study the antibiotic susceptibility of 693 strains of bacteria and its relation to the plasmid. Methods A modified Birnboim method was used for plasmid extraction. Results A 60 U plasmid of EPEC O 127 : H 6 carried multiresistant genes to 3 antibiotics; a 98 kb plasmid of S.typhimurium possessed multi resistant genes to 5 antibiotics; and a 1.9 U plasmid of S. aureus carried multi resistant genes to 10 antibiotics. The sensitivity rates of S. aureus to gentamicin, oxacillin, erythromycin and cephalothin were all 100% in 1986, but they dropped to 48.1%, 46.9%, 9.9% and 7.4%, respectively, in 1988 1989. During this peroid, however, 97.5% of S. auerus continued to be sensitive to amikacin. The sensitivity rates of S. typhimurium, EPEC and P. aeruginosa to amikacin were 96.9%, 95.5%, and 94.3%, respectively. Conclusion Amikacin may be the drug of choice in treatment of neonatal septicemia in China.