St Paul's Eye Unit, Royal Liverpool University Hospital, Liverpool, United Kingdom.
Invest Ophthalmol Vis Sci. 2013 May 1;54(5):3410-6. doi: 10.1167/iovs.12-11276.
To determine the prevalence, genetic diversity, and clinical relevance of the lukSF-PV gene, encoding the bacterial toxin Panton-Valentine leukocidin, in Staphylococcus aureus isolates from cases of bacterial keratitis in the United Kingdom.
Multiplex PCRs investigating carriage of lukSF-PV and mecA were performed on S. aureus isolates from patients. The lukSF-PV operon was sequenced to investigate its diversity, and multilocus sequence typing to test for a clonal relationship between lukSF-PV isolates. Antimicrobial minimum inhibitory concentrations (MICs) and clinical outcome data were compared for isolates characterized as lukSF-PV+ve, mecA+ve, and lukSF-PV/mecA-ve.
Of 95 isolates, 9 (9.5%) were lukSF-PV+ve, 9 (9.5%) mecA+ve, and 1 was positive for both. Five single nucleotide polymorphisms were found in lukSF-PV genes of seven strains. There was no significant difference between the MICs of lukSF-PV/mecA-ve and lukSF-PV+ve isolates to the antimicrobials tested, except for tigecycline (P < 0.05). The mecA+ve isolates had significantly higher mean MICs to meropenem and fluoroquinolones (P < 0.05). There were nonsignificant trends for healing and treatment times, ulcer and scar size, and overall clinical score to be greater in the lukSF-PV+ve group (P < 0.05). The proportion of patients, however, who required surgery was significantly greater among patients with lukSF-PV+ve isolates with an odds ratio of 7.8 (95% CI 1-42, P = 0.018) for patients requiring surgery.
lukSF-PV+ve isolates were associated with a trend to worse clinical outcome and more surgical interventions, with an effect unrelated to MICs. This suggests that lukSF-PV may be an important virulence factor in S. aureus-associated keratitis.
确定英国细菌性角膜炎患者分离的金黄色葡萄球菌中编码细菌毒素 Panton-Valentine 白细胞溶解素的 lukSF-PV 基因的流行率、遗传多样性和临床相关性。
对来自患者的金黄色葡萄球菌分离株进行多重 PCR 检测 lukSF-PV 和 mecA 的携带情况。对 lukSF-PV 操纵子进行测序以研究其多样性，并进行多位点序列分型以检测 lukSF-PV 分离株之间的克隆关系。比较被鉴定为 lukSF-PV+ve、mecA+ve 和 lukSF-PV/mecA-ve 的分离株的抗生素最小抑菌浓度 (MIC) 和临床结果数据。
在 95 株分离株中，9 株（9.5%）为 lukSF-PV+ve，9 株（9.5%）为 mecA+ve，1 株同时为阳性。在 7 株菌株的 lukSF-PV 基因中发现了 5 个单核苷酸多态性。除替加环素外（P < 0.05），lukSF-PV/mecA-ve 和 lukSF-PV+ve 分离株对测试的抗生素的 MIC 无显著差异。mecA+ve 分离株对美罗培南和氟喹诺酮类药物的平均 MIC 显著较高（P < 0.05）。lukSF-PV+ve 组在愈合和治疗时间、溃疡和疤痕大小以及总体临床评分方面有更大的趋势（P < 0.05）。然而，需要手术的患者中，lukSF-PV+ve 分离株的患者比例显著更高，需要手术的患者的优势比为 7.8（95%CI 1-42，P = 0.018）。
lukSF-PV+ve 分离株与临床结局恶化和更多手术干预的趋势相关，与 MIC 无关。这表明 lukSF-PV 可能是金黄色葡萄球菌相关性角膜炎的一个重要毒力因子。
