Department of Microbiology, University of Mississippi Medical Center, 2500 North State Street, Jackson, Mississippi 39216, USA.
Adv Ther. 2010 Dec;27(12):933-40. doi: 10.1007/s12325-010-0082-x. Epub 2010 Oct 22.
antibiotic and steroid combination therapies, such as tobramycin with dexamethasone, are often used in ophthalmology to treat or prevent infection and inflammation. The purpose of this study was to use a model of Staphylococcus aureus keratitis to quantify and compare the effectiveness of a standard tobramycin and dexamethasone combined therapy, with each drug individually, and with a new formulation of the two drugs in a xanthan gum vehicle.
rabbit corneas were intrastromally injected with a methicillin-sensitive S. aureus (MSSA) or a methicillin-resistant S. aureus (MRSA) strain. Rabbit eyes were treated every hour from 10 to 15 hours postinfection (PI) with 0.1% dexamethasone, 0.3% tobramycin, 0.3% tobramycin with 0.1% dexamethasone, or 0.3% tobramycin with 0.05% dexamethasone in a xanthan gum vehicle (ST). Slit lamp examinations (SLE) were performed on infected eyes and pathology scored at 15 hours PI. At 16 hours PI, colony forming units (CFUs) per cornea were quantified.
the CFUs in eyes treated with dexamethasone alone were similar to untreated control eyes for MSSA or MRSA infections. All other treatment groups had significantly less CFUs per cornea than untreated eyes. The eyes treated with the ST formulation had significantly fewer CFUs per cornea than all other treatment groups when infected with MSSA or MRSA. The SLE scores of MSSA or MRSA infected eyes treated with tobramycin alone were similar to untreated control eyes. All other treatment groups had significantly lower SLE scores than untreated controls eyes, but were not significantly different from each other.
the results of this study demonstrated that the tobramycin and dexamethasone combination therapy with a xanthan gum vehicle has an improved bactericidal effectiveness compared to the commercially available formulation, and maintains a similar anti-inflammatory effect while containing half the amount of steroid.
抗生素和类固醇联合疗法，如妥布霉素联合地塞米松，常用于眼科治疗或预防感染和炎症。本研究的目的是使用金黄色葡萄球菌角膜炎模型，定量比较和评估标准妥布霉素和地塞米松联合治疗的效果，以及单独使用每种药物的效果，还评估了两种药物在黄原胶载体中的新配方的效果。
用甲氧西林敏感金黄色葡萄球菌（MSSA）或耐甲氧西林金黄色葡萄球菌（MRSA）菌株经基质内注射兔角膜。感染后 10 至 15 小时，每小时用 0.1%地塞米松、0.3%妥布霉素、0.3%妥布霉素加 0.1%地塞米松或 0.3%妥布霉素加 0.05%地塞米松在黄原胶载体（ST）中治疗兔眼。对感染眼进行裂隙灯检查（SLE），并在感染后 15 小时进行病理评分。感染后 16 小时，定量每只角膜的菌落形成单位（CFU）。
单独用地塞米松治疗的眼 CFU 与 MSSA 或 MRSA 感染的未治疗对照眼相似。所有其他治疗组的每只角膜 CFU 均明显少于未治疗眼。用 ST 制剂治疗的 MSSA 或 MRSA 感染眼的每只角膜 CFU 明显少于所有其他治疗组。单独用妥布霉素治疗的 MSSA 或 MRSA 感染眼的 SLE 评分与未治疗对照眼相似。所有其他治疗组的 SLE 评分均明显低于未治疗对照组，但彼此之间无显著差异。
本研究结果表明，与市售制剂相比，含黄原胶载体的妥布霉素和地塞米松联合疗法具有更好的杀菌效果，同时含有一半剂量的类固醇，保持了类似的抗炎效果。
