Department of Ophthalmology, Chang Gung Memorial Hospital, Linkou Medical Center, Taoyuan, Taiwan.
College of Medicine, Chang Gung University, Taoyuan, Taiwan.
Invest Ophthalmol Vis Sci. 2023 Oct 3;64(13):33. doi: 10.1167/iovs.64.13.33.
Staphylococcus epidermidis, a commensal, has emerged as an important opportunistic pathogen, particularly methicillin-resistant S. epidermidis (MRSE). The mechanism behind this transformation remains unclear. This study aimed to investigate the molecular and phenotypic characteristics of MRSE isolated from healthy conjunctiva and ocular infections.
We collected MRSE isolates from two groups: healthy conjunctiva from patients undergoing cataract surgeries and ocular infections at our hospital. Genotypic analysis included pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), staphylococcal cassette chromosome mec (SCCmec), and biofilm-related genes (icaA, aap, and bhp). Additionally, phenotypic data on biofilm production and antibiotic susceptibility were recorded.
A total of 86 isolates, including 42 from healthy conjunctiva and 44 from ocular infections, were analyzed. MLST identified 21 sequence types (STs), with ST59 being the most frequent (n = 33, 39.5%), followed by ST130 (n = 10, 11.6%), ST57 (n = 6, 7.0%), and ST2 (n = 6, 7.0%). All isolates were categorized in 23 PFGE types, and SCCmec IV was the most prevalent SCCmec type (n = 52, 60.5%). The two sources of isolates exhibited overlapping molecular types and phenotypic traits, although the ocular infection isolates exhibited significantly higher multidrug resistance compared to healthy conjunctiva isolates (P = 0.032). When contrasting ST59 with non-ST59, ST59 displayed a significantly higher presence of aap (100%) and bhp (69.7%) while lacking icaA (0%). ST59 also showed lower susceptibility to fluoroquinolones compared to non-ST59 (42.4%-54.5% vs. 75.5%-83.0%; P < 0.01).
MRSE isolates from healthy conjunctiva and ocular infections demonstrated a degree of resemblance. Specific strains, notably ST59, exhibited distinctive characterizations.
表皮葡萄球菌是一种共生菌，已成为一种重要的机会致病菌，特别是耐甲氧西林表皮葡萄球菌（MRSE）。其转变的机制尚不清楚。本研究旨在研究从健康结膜和眼部感染中分离出的 MRSE 的分子和表型特征。
我们收集了来自两组 MRSE 分离株：在我院接受白内障手术的健康结膜和眼部感染患者。基因分析包括脉冲场凝胶电泳（PFGE）、多位点序列分型（MLST）、葡萄球菌盒染色体 mec（SCCmec）和生物膜相关基因（icaA、aap 和 bhp）。此外，还记录了生物膜产生和抗生素敏感性的表型数据。
共分析了 86 株分离株，其中 42 株来自健康结膜，44 株来自眼部感染。MLST 鉴定出 21 种序列型（ST），其中 ST59 最为常见（n = 33，39.5%），其次是 ST130（n = 10，11.6%）、ST57（n = 6，7.0%）和 ST2（n = 6，7.0%）。所有分离株均分为 23 种 PFGE 型，SCCmec IV 是最常见的 SCCmec 型（n = 52，60.5%）。尽管眼部感染分离株的多药耐药性明显高于健康结膜分离株（P = 0.032），但两种来源的分离株表现出重叠的分子类型和表型特征。当比较 ST59 与非 ST59 时，ST59 明显更易携带 aap（100%）和 bhp（69.7%），而不携带 icaA（0%）。与非 ST59 相比，ST59 对氟喹诺酮类药物的敏感性也较低（42.4%-54.5%比 75.5%-83.0%；P < 0.01）。
来自健康结膜和眼部感染的 MRSE 分离株表现出一定程度的相似性。特定菌株，特别是 ST59，表现出独特的特征。
