Department of Veterinary Clinic and Surgery, São Paulo State University-FCAV/UNESP, Jaboticabal, São Paulo, Brazil.
Laboratory of Molecular Epidemiology, Department of Preventive Veterinary Medicine and Animal Reproduction, São Paulo State University-FCAV/UNESP, Jaboticabal, São Paulo, Brazil.
Vet Microbiol. 2018 Jan;213:95-101. doi: 10.1016/j.vetmic.2017.11.028. Epub 2017 Nov 21.
Bacterial contamination of the anterior chamber during cataract surgery is one of the main responsible for endophthalmitis postoperative. Phacoemulsification is a less invasive technique for cataract treatment, although it does not exclude the possibility of contamination. In this study, bacterial contaminants of aqueous humor collected pre- and post-phacoemulsification with intraocular lens implantation (IOL) of twenty dogs were identified. As the conjunctival microbiota constitute a significant source of anterior chamber contamination, bacterial isolates from aqueous humor were genetically compared with those present in the conjunctival surface of the patients. Three dogs presented bacterial growth in both aqueous humor and conjunctival surface samples. Bacterial isolates from these samples were grouped according to their genetic profiles by repetitive-element PCR (rep-PCR) and their representatives were identified by 16S rRNA sequencing. Isolates from conjunctival surface were identified as Enterobacter spp., Staphylococcus spp. and S. aureus; and from aqueous humor samples as Enterobacter spp., Pantoea spp., Streptococcus spp. and Staphylococcus spp., respectively in decreasing order of prevalence. According to the rep-PCR analysis, 16.6% of Enterobacter spp. isolates from conjunctival surface were genetically similar to those from aqueous humor. The rest of isolates encountered in aqueous humor were genetically distinct from those of conjunctival surface. The significant genetic diversity of bacterial isolates found in the aqueous humor samples after surgery denoted the possibility of anterior chamber contamination during phacoemulsification by bacteria not only from conjunctival surface but also from different sources related to surgical environment.
白内障手术过程中前房的细菌污染是术后眼内炎的主要原因之一。虽然超声乳化术是一种治疗白内障的微创技术，但并不能排除污染的可能性。在这项研究中，我们对二十只狗进行了白内障超声乳化术联合人工晶状体（IOL）植入术前和术后房水的细菌污染物进行了鉴定。由于结膜微生物群是前房污染的重要来源，因此我们将房水中的细菌分离株与患者结膜表面的细菌分离株进行了基因比较。有三只狗的房水和结膜表面样本中均有细菌生长。根据其遗传图谱，我们通过重复元件 PCR（rep-PCR）将这些样本中的细菌分离株进行分组，并通过 16S rRNA 测序鉴定其代表株。结膜表面的分离株鉴定为肠杆菌属、葡萄球菌属和金黄色葡萄球菌；而房水样本中则分别为肠杆菌属、泛菌属、链球菌属和葡萄球菌属，其出现频率依次递减。根据 rep-PCR 分析，结膜表面的 16.6%肠杆菌属分离株与房水中的分离株在基因上相似。而房水中遇到的其余分离株在基因上与结膜表面的分离株不同。手术后房水样本中分离出的细菌具有显著的遗传多样性，这表明在超声乳化术中前房可能不仅受到结膜表面细菌的污染，还可能受到与手术环境相关的不同来源细菌的污染。
