Division of Nephrology, Department of Medicine, University of Calgary, Calgary, Alberta, Canada.
Perit Dial Int. 2010 Nov-Dec;30(6):652-6. doi: 10.3747/pdi.2010.00010.
Peritoneal dialysis (PD)-related peritonitis is a common and morbid complication of PD. Bacteria are able to create a biofilm on the PD catheter, which can be a source of recurrent infection. Biofilms undergo a phenotypic change resulting in increased antibiotic resistance. ♢
21 clinical isolates of different patients with PD peritonitis secondary to Staphylococcus aureus were collected. They were analyzed for their antibiotic susceptibility in the planktonic form using the standard minimum inhibitory concentration (MIC) and in a biofilm using minimum biofilm eradication concentration (MBEC). Chi-square was used to compare the sensitivity results. ♢
The isolates were susceptible to all the antibiotics tested using MIC. Every antibiotic except gentamicin lost its efficacy when the bacteria were grown in a biofilm (p > 0.05). The change in susceptibility was statistically significant to a level of p < 0.001 for all antibiotics tested. ♢
In PD peritonitis that is long standing, recurrent, or not responsive to therapy, MBEC testing should be considered as a biofilm may be present. Gentamicin should be strongly considered over other agents for empiric gram-negative coverage as it may be providing synergy in the setting of Staphylococcus aureus. Also, the newer anti-staphylococcal drugs should be tested for their performance in a biofilm using the MBEC method.
腹膜透析（PD）相关腹膜炎是 PD 的一种常见且严重的并发症。细菌能够在 PD 导管上形成生物膜，这可能是反复感染的根源。生物膜会发生表型变化，导致抗生素耐药性增加。
收集了 21 例不同 PD 相关性腹膜炎患者的临床分离株金黄色葡萄球菌。采用标准最小抑菌浓度（MIC）测定浮游菌和最低生物膜清除浓度（MBEC）测定生物膜中的抗生素敏感性。采用卡方检验比较敏感性结果。
分离株对所有测试的抗生素均敏感，使用 MIC 时。除庆大霉素外，所有抗生素在生物膜中生长时均失去疗效（p>0.05）。所有测试抗生素的敏感性变化均具有统计学意义（p<0.001）。
在 PD 相关性腹膜炎病程长、反复发作或对治疗无反应时，应考虑进行 MBEC 检测，因为可能存在生物膜。在金黄色葡萄球菌感染中，庆大霉素应优于其他药物作为经验性革兰氏阴性菌覆盖的药物，因为它可能具有协同作用。此外，应使用 MBEC 方法测试新型抗葡萄球菌药物在生物膜中的性能。
