背景:金黄色葡萄球菌(S.金黄色葡萄球菌)经常定植在人类皮肤上,上呼吸道和生殖道。在女性生殖道,它可以在阴道分娩过程中传递给新生儿,导致普通的定植,或新生儿感染,特别是脐残端败血症,烫伤皮肤综合征,关节炎,或菌血症/败血症。这些感染是由葡萄球菌毒力因子介导的,例如(i)葡萄球菌肠毒素A,B,C,D,E由海编码,seb,sec,SED,看到基因,(ii)由eta和etb基因编码的剥脱性毒素A和B,(iii)由tst基因编码的毒性休克综合征毒素1(TSST-1),(iv)Panton-Valentine杀白细胞素(PVL)由pvl基因编码,和(v)由hla和hld基因编码的溶血素α和δ,分别。我们确定了该人群中具有一个或多个毒力因子基因的金黄色葡萄球菌和耐甲氧西林金黄色葡萄球菌(MRSA)的患病率。
方法:这是一项横断面研究,使用来自乌干达氯己定(CHX)临床试验研究的85株金黄色葡萄球菌分离物。分离株是通过培养1472名分娩妇女的阴道拭子(VS)获得的,冷冻在零下80摄氏度,然后解冻,亚培养,并测试了选定的毒力基因海,seb,sec,SED,看到eta,ETB,tst,pvl,hla和hld,和甲氧西林抗性决定基因(mecA)。使用SPSS版本20对数据进行分析。
结果:在85株金黄色葡萄球菌分离株中,13株(15.3%)对一种或多种毒力因子基因呈阳性,如下:pvl9/85(10.6%),hld5/85(5.9%),sea1/85(1.2%)和seb基因1/85(1.2%)。其他毒力基因(秒,SED,see,eta,ETB,在任何分离物中均未检测到hla和tst)。在55.3%(47/85)的分离物中检测到MRSA,但其中只有两个携带pvl毒力基因。
结论:这项研究表明,15%的金黄色葡萄球菌定植在乌干达中部分娩的母亲的女性下生殖道携带一个或多个毒力基因,主要是pvl,提示新生儿在产妇产道中获得的金黄色葡萄球菌感染的可能性。超过一半的分离物是MRSA。
BACKGROUND: Staphylococcus aureus (S. aureus) often colonizes the human skin, upper respiratory and genital tracts. In the female genital tract, it can be passed on to the newborn during vaginal delivery leading to either ordinary colonization, or neonatal infections notably umbilical stump sepsis, scalded skin syndrome, arthritis, or bacteraemia/sepsis. These infections are mediated by staphylococcal virulence factors such as (i) Staphylococcal Enterotoxins A, B, C, D, and E encoded by the sea, seb, sec, sed, see genes, (ii) Exfoliative Toxins A and B encoded by the eta and etb genes, (iii) Toxic Shock Syndrome Toxin 1 (TSST-1) encoded by the tst gene, (iv) Panton-Valentine Leukocidin (PVL) encoded by the pvl gene, and (v) Hemolysins alpha and delta encoded by the hla and hld genes, respectively. We determined the prevalence of S. aureus possessing one or more virulence factor genes and of methicillin resistant Staphylococcus aureus (MRSA) in this population.
METHODS: This was a cross-sectional study, which used 85 S. aureus isolates from the Chlorohexidine (CHX) clinical trial study in Uganda. The isolates had been obtained by culturing vaginal swabs (VS) from 1472 women in labour, frozen at minus 80oC, then thawed, sub-cultured, and tested for the selected virulence genes sea, seb, sec, sed, see eta, etb, tst, pvl, hla and hld, and for the methicillin resistance determining gene (mecA). Data were analyzed using SPSS version 20.
RESULTS: Of the 85 S. aureus isolates 13 (15.3%) were positive for one or more virulence factor genes, as follows: pvl 9/85 (10.6%), hld 5/85 (5.9%), sea 1/85 (1.2%) and seb genes 1/85 (1.2%). The other virulence genes (sec, sed, see, eta, etb, hla and tst) were not detected in any of the isolates. MRSA was detected in 55.3% (47/85) of the isolates, but only two of these carried the pvl virulence gene.
CONCLUSIONS: This study demonstrated that 15% of the S. aureus colonizing the female lower genital tract of mothers in labour in central Uganda carried one or more virulence genes, mostly pvl, indicating potential for newborn infection with S. aureus acquired in the maternal birth canal. More than half of the isolates were MRSA.