Department of Medical Microbiology, Ankara University School of Medicine, Ankara, Turkey
Balkan Med J. 2020 Jun 1;37(4):215-221. doi: 10.4274/balkanmedj.galenos.2020.2019.8.21. Epub 2020 Apr 9.
Coagulase-negative staphylococci, which belong to the normal microbiota of the skin and mucous membranes, are opportunistic pathogens. , a newly described protein, is thought to play an important role in nasal colonization and methicillin-resistant virulence, and it may be acquired from coagulase-negative staphylococci by horizontal gene transfer. It has been considered that understanding the function of gene may help clarify the relevance of the different adhesion mechanisms in the pathogenesis of infections associated with biofilm.
To investigate the gene presence, staphylococcal cassette chromosome types, and antimicrobial resistance patterns of invasive and noninvasive coagulase-negative staphylococci isolates.
Cross-sectional study.
The study included a total of 180 coagulase-negative staphylococci strains. Non-invasive isolates (n=91) were obtained from the hands of healthy volunteers who do not work at the hospital (n=30), the nasal vestibule of healthy volunteer hospital workers (n=26), and central venous catheter (n=35). Invasive isolates (n=89) were isolated from peripheral blood cultures of inpatients who do not have catheters. All isolates were identified by conventional microbiological methods, automated systems, and, if needed, with matrix-assisted laser desorption/ionization-time of flight. Staphylococcal cassette chromosome typing, and gene detection, antibiotic susceptibility, and gene sequence analysis were performed.
Peripheral blood, central venous catheter colonization, and nasal vestibule isolates were positive for the gene, whereas hand isolates were negative. gene was present in 17 isolates, and no statistical significance was found between invasive and noninvasive isolates (p=0.173). Sequence analysis of the genes showed high homology to related proteins of phage SPbeta-like and RP62A. staphylococcal cassette chromosome type V was the most prevalent regardless of species. staphylococcal cassette chromosome type II was more frequent in invasive isolates and found to be statistically important for invasive and noninvasive isolates (p=0.029). isolates had the overall highest resistance rates. Resistance to ciprofloxacin, trimethoprim-sulfamethoxazole, and erythromycin was found to be higher in isolates from catheter and blood culture. isolates had the highest rate for inducible clindamycin resistance. None of the isolates were resistant to vancomycin, teicoplanin, and linezolid.
The gene is detected in 9.44% of the isolates. There is no statistical difference between the -positive and -negative isolates in terms of antibacterial resistance and the presence of and SCC types. Further studies about the role of at virulence in coagulase-negative staphylococci, especially from clinical samples such as tracheal aspirate and abscess isolates, and distribution of staphylococcal cassette chromosome types are needed.
凝固酶阴性葡萄球菌属于皮肤和黏膜正常菌群，是机会致病菌。新描述的蛋白 被认为在鼻腔定植和耐甲氧西林金黄色葡萄球菌毒力中发挥重要作用，它可能通过水平基因转移从凝固酶阴性葡萄球菌获得。人们认为，了解 基因的功能可能有助于阐明与生物膜相关感染的不同粘附机制的相关性。
研究侵袭性和非侵袭性凝固酶阴性葡萄球菌分离株的 基因存在情况、葡萄球菌盒式染色体 型和抗菌药物耐药模式。
横断面研究。
该研究共纳入 180 株凝固酶阴性葡萄球菌。非侵袭性分离株（n=91）取自手部，这些手部来自于未在医院工作的健康志愿者（n=30）、健康志愿者医院工作人员的鼻腔前庭（n=26）和中心静脉导管（n=35）。侵袭性分离株（n=89）取自无导管住院患者的外周血培养物。所有分离株均通过常规微生物学方法、自动化系统进行鉴定，如果需要，还通过基质辅助激光解吸/电离飞行时间进行鉴定。进行葡萄球菌盒式染色体 型、 基因检测、抗生素药敏试验和 基因序列分析。
外周血、中心静脉导管定植和鼻腔前庭分离株 基因阳性，而手部分离株阴性。17 株分离株存在 基因，侵袭性和非侵袭性分离株之间无统计学差异（p=0.173）。对 基因的序列分析显示与相关噬菌体 SPβ样和 RP62A 的蛋白高度同源。无论种属如何，葡萄球菌盒式染色体 型 V 最为普遍。葡萄球菌盒式染色体 型 II 在侵袭性分离株中更为常见，且对侵袭性和非侵袭性 分离株具有统计学意义（p=0.029）。 分离株的总体耐药率最高。导管和血培养分离株对环丙沙星、甲氧苄啶-磺胺甲恶唑和红霉素的耐药率较高。 分离株诱导型克林霉素耐药率最高。分离株均对万古霉素、替考拉宁和利奈唑胺敏感。
在 9.44%的分离株中检测到 基因。在抗菌药物耐药性和 基因及葡萄球菌盒式染色体 型存在方面，-阳性和-阴性分离株之间无统计学差异。需要进一步研究 基因在凝固酶阴性葡萄球菌，尤其是从气管抽吸物和脓肿分离株等临床样本中的毒力方面的作用，以及葡萄球菌盒式染色体 型的分布。
