Baer J C, Nirankari V S, Glaros D S
Department of Ophthalmology, University of Maryland, Baltimore.
Cornea. 1989;8(2):131-4.
Our experience with three cases of Streptococcus viridans endophthalmitis, following penetrating keratoplasty, prompted us to investigate the ability of gentamicin-supplemented McCarey-Kaufman (M-K) medium to kill S. viridans contaminants. After inoculation of 20 cc of gentamicin-supplemented M-K with S. viridans, the M-K was exposed to temperature conditions similar to those that would be encountered by a donor cornea during storage (4 degrees C) and preoperative warming prior to keratoplasty (23 degrees C). Colony counts were performed at regular intervals. After 1 h of warming, no reduction in the initial inoculum had occurred. This is in contrast to results from similar experiments with Staphylococcus aureus, Staphylococcus epidermidis, and Pseudomonas aeruginosa in which more than 1 log unit of killing occurred after 1 h. While previously reported clinical experience has demonstrated an overall low incidence of postkeratoplasty endophthalmitis using gentamicin-supplemented M-K, our own recent clinical and laboratory data suggest that additional or alternate antibiotic coverage for S. viridans may be prudent.
我们在穿透性角膜移植术后遇到3例草绿色链球菌性眼内炎的经历，促使我们研究添加庆大霉素的麦凯里-考夫曼（M-K）培养基杀灭草绿色链球菌污染物的能力。在用草绿色链球菌接种20毫升添加庆大霉素的M-K培养基后，将M-K培养基置于与供体角膜在储存期间（4℃）以及角膜移植术前预热（23℃）时所经历的温度条件相似的环境中。定期进行菌落计数。在预热1小时后，初始接种量没有减少。这与用金黄色葡萄球菌、表皮葡萄球菌和铜绿假单胞菌进行的类似实验结果形成对比，在那些实验中，1小时后有超过1个对数单位的杀灭效果。虽然先前报道的临床经验表明，使用添加庆大霉素的M-K培养基后角膜移植术后眼内炎的总体发生率较低，但我们自己最近的临床和实验室数据表明，对草绿色链球菌采用额外的或替代的抗生素覆盖可能是谨慎的做法。
