Kwon An Sung, Park Gwang Chul, Ryu So Yeon, Lim Dong Hoon, Lim Dong Yoon, Choi Chul Hee, Park Yoonkyung, Lim Yong
Department of Microbiology, Medical School, Chosun University, 375 Seosuk-dong, Dong-gu, Gwangju 501-759, Republic of Korea.
Int J Antimicrob Agents. 2008 Jul;32(1):68-72. doi: 10.1016/j.ijantimicag.2008.02.009. Epub 2008 Jun 5.
The biofilm-forming capacity of Staphylococcus aureus contributes to antibiotic resistance, but whether antibiotic-resistant strains have the capacity to form biofilms has not yet been determined. Therefore, we recovered 101 clinical isolates of S. aureus and performed antibiotic susceptibility testing for 30 antibiotics using a VITEK II automatic system. We then carried out a biofilm assay on 96-well polystyrene plates. In addition, the presence of IS256 involved in the variation of biofilm phases of S. aureus was determined by polymerase chain reaction. The prevalence of IS256 was significantly related to multidrug resistance as well as biofilm expression, with biofilm positivity in 27 (39.7%) of the 68 IS256-positive strains and 3 (9.1%) of the 33 IS256-negative strains. In our analysis of the relationship between meticillin resistance and biofilm formation, we found that the rate of biofilm positivity was 37.9% (25/66) for meticillin-resistant strains and 14.3% (5/35) for meticillin-susceptible strains (P<0.05). Staphylococcal cassette chromosome mec (SCCmec) typing found that SCCmec type IV was most prevalent, comprising 14 (56.0%) of the 25 biofilm-positive, meticillin-resistant strains. A statistical analysis testing the relationship between multidrug resistance and biofilm formation revealed a significantly higher rate of biofilm development in strains with greater multiresistance compared with strains with less multiresistance. Our results suggest that the multidrug-resistant clinical isolates of S. aureus have a greater likelihood of developing biofilms on medical devices.
金黄色葡萄球菌形成生物膜的能力会导致抗生素耐药性，但抗生素耐药菌株是否具有形成生物膜的能力尚未确定。因此，我们收集了101株金黄色葡萄球菌临床分离株，并使用VITEK II自动系统对30种抗生素进行了药敏试验。然后，我们在96孔聚苯乙烯板上进行了生物膜检测。此外，通过聚合酶链反应确定了参与金黄色葡萄球菌生物膜阶段变化的IS256的存在。IS256的流行率与多重耐药性以及生物膜表达显著相关，68株IS256阳性菌株中有27株（39.7%）生物膜呈阳性，33株IS256阴性菌株中有3株（9.1%）生物膜呈阳性。在我们对甲氧西林耐药性与生物膜形成之间关系的分析中，我们发现甲氧西林耐药菌株的生物膜阳性率为37.9%（25/66），甲氧西林敏感菌株的生物膜阳性率为14.3%（5/35）（P<0.05）。葡萄球菌盒式染色体mec（SCCmec）分型发现，SCCmec IV型最为普遍，在25株生物膜阳性、甲氧西林耐药菌株中占14株（56.0%）。一项检验多重耐药性与生物膜形成之间关系的统计分析显示，与多重耐药性较低的菌株相比，多重耐药性较高的菌株生物膜形成率显著更高。我们的结果表明，金黄色葡萄球菌的多重耐药临床分离株在医疗器械上形成生物膜的可能性更大。
