Anagnostakos Konstantinos, Hitzler Philip, Pape Dietrich, Kohn Dieter, Kelm Jens
Klinik für Orthopädie und Orthopädische Chirurgie, Universitätsklinikum des Saarlandes, Homburg/Saar, Germany.
Acta Orthop. 2008 Apr;79(2):302-7. doi: 10.1080/17453670710015120.
Implantation of antibiotic-loaded beads is used for orthopedic infections. However, recent in vitro reports have emphasized that bacteria can persist on-or even colonize-antibiotic-impregnated bone cement. We therefore assessed whether bacterial adherence and growth could be determined on gentami-cin- and gentamicin-vancomycin-loaded beads that had been removed after eradication of infection.
We bacteriologically examined 18 chains of antibiotic-loaded beads (11 gentami-cin-loaded, 7 gentamicin-vancomycin-loaded) that had been implanted because of orthopedic infections. Among the causative agents, Staphylococcus epidermidis, Staph-ylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA) were the most frequent organisms identified.
In 4 cases (3 with S. epidermidis and one with MRSA), we found that there was persistence of bacterial growth on the beads. S. epidermidis strains persisted only on gentamicin-loaded beads, while MRSA could grow on gentamicin-vancomycin-impregnated cement. In one case, the emergence of a gentamicin-resistant S. epidermidis strain was observed despite the fact that preoperative samples of S. epidermidis from this patient had been susceptible to the antibiotic.
Persistence of bacterial growth on bone cement remains a hazardous problem in orthopedic surgery. Adherence of bacteria to cement can lead to emergence of bacterial resistance to antibiotics and might result in clinical recurrence of infection.
负载抗生素的骨珠植入术用于治疗骨科感染。然而，近期的体外研究报告强调，细菌可在负载抗生素的骨水泥上持续存在，甚至定植。因此，我们评估了在感染根除后取出的庆大霉素负载骨珠和庆大霉素-万古霉素负载骨珠上，是否能够检测到细菌黏附和生长情况。
我们对18串因骨科感染而植入的负载抗生素的骨珠进行了细菌学检查（11串为庆大霉素负载骨珠，7串为庆大霉素-万古霉素负载骨珠）。在病原体中，表皮葡萄球菌、金黄色葡萄球菌和耐甲氧西林金黄色葡萄球菌（MRSA）是最常见的菌种。
在4例病例中（3例为表皮葡萄球菌感染，1例为MRSA感染），我们发现骨珠上存在细菌持续生长的情况。表皮葡萄球菌菌株仅在庆大霉素负载骨珠上持续存在，而MRSA可在庆大霉素-万古霉素浸渍的骨水泥上生长。在1例病例中，尽管该患者术前的表皮葡萄球菌样本对抗生素敏感，但仍观察到一株耐庆大霉素的表皮葡萄球菌菌株出现。
骨水泥上细菌的持续生长在骨科手术中仍然是一个危险问题。细菌黏附于骨水泥可导致细菌对抗生素产生耐药性，并可能导致感染的临床复发。
