Lee L H, Zaidman G W, Van Horn K
Department of Ophthalmology, Westchester Medical Center, New York Medical College, Valhalla 10595, USA.
Cornea. 2001 Mar;20(2):179-82. doi: 10.1097/00003226-200103000-00014.
The conventional treatment of Nocardia keratitis is with topical sulfonamides. Recently, topical trimethoprim and sulfamethoxazole (Bactrim) has been suggested as treatment. This study compares the in vitro efficacy against Nocardia asteroides of Bactrim and various ratios of trimethoprim and a sulfonamide.
Antibiotic disks were soaked with various ratios of trimethoprim and sulfacetamide sodium. They contained trimethoprim alone, sulfacetamide sodium alone, and both trimethoprim and sulfacetamide sodium at ratios of 1:40, 1:20, and 1:5. Disks containing Bactrim were also prepared. Each disk was placed on blood agar plates streaked with N. asteroides. The plates were incubated at 37 degrees C for 72 hours and then examined.
Trimethoprim alone showed minimal effect. Sulfacetamide sodium alone had a clearance zone of 12 mm. The plates of trimethoprim and sulfacetamide sodium at ratios of 1:40, 1:20, and 1:5 had clearance zones of 14 mm, 17 mm, and 27 mm, respectively. Bactrim had a clearance zone of 70 mm.
Trimethoprim or sulfacetamide sodium alone is not as effective as both drugs together. As the ratio of the two drugs was changed, potency differed against Nocardia organisms. Bactrim was the most effective antibiotic against Nocardia organisms. It should be the recommended agent for the treatment of Nocardia keratitis.
诺卡菌性角膜炎的传统治疗方法是局部使用磺胺类药物。最近，有人建议使用局部用甲氧苄啶和磺胺甲恶唑（复方新诺明）进行治疗。本研究比较了复方新诺明以及不同比例的甲氧苄啶与一种磺胺类药物对星形诺卡菌的体外疗效。
将抗生素纸片用不同比例的甲氧苄啶和磺胺醋酰钠浸泡。纸片分别单独含有甲氧苄啶、单独含有磺胺醋酰钠，以及甲氧苄啶和磺胺醋酰钠按1:40、1:20和1:5的比例混合。还制备了含复方新诺明的纸片。将每张纸片置于接种了星形诺卡菌的血琼脂平板上。平板在37℃孵育72小时，然后进行检查。
单独的甲氧苄啶显示出最小的效果。单独的磺胺醋酰钠有12毫米的抑菌圈。甲氧苄啶和磺胺醋酰钠比例为1:40、1:20和1:5的平板，抑菌圈分别为14毫米、17毫米和27毫米。复方新诺明有70毫米的抑菌圈。
单独的甲氧苄啶或磺胺醋酰钠不如两者联合有效。随着两种药物比例的变化，对诺卡菌属微生物的效力有所不同。复方新诺明是针对诺卡菌属微生物最有效的抗生素。它应是治疗诺卡菌性角膜炎的推荐药物。
