Koning Sander, van Belkum Alex, Snijders Susan, van Leeuwen Willem, Verbrugh Henri, Nouwen Jan, Op 't Veld Mariet, van Suijlekom-Smit Lisette W A, van der Wouden Johannes C, Verduin Cees
Department of General Practice, Erasmus MC University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands.
J Clin Microbiol. 2003 Jul;41(7):3017-21. doi: 10.1128/JCM.41.7.3017-3021.2003.
Nonbullous impetigo is a common skin infection in children and is frequently caused by Staphylococcus aureus. Staphylococcal toxins and especially exfoliative toxin A are known mediators of bullous impetigo in children. It is not known whether this is also true for nonbullous impetigo. We set out to analyze clonality among clinical isolates of S. aureus from children with nonbullous impetigo living in a restricted geographical area in The Netherlands. We investigated whether staphylococcal nasal carriage and the nature of the staphylococcal strains were associated with the severity and course of impetigo. Bacterial isolates were obtained from the noses and wounds of children suffering from impetigo. Strains were genetically characterized by pulsed-field gel electrophoresis-mediated typing and binary typing, which was also used to assess toxin gene content. In addition, a detailed clinical questionnaire was filled in by each of the participating patients. Staphylococcal nasal carriage seems to predispose the patients to the development of impetigo, and 34% of infections diagnosed in the Rotterdam area are caused by one clonal type of S. aureus. The S. aureus strains harbor the exfoliative toxin B (ETB) gene as a specific virulence factor. In particular, the numbers (P = 0.002) and sizes (P < 0.001) of the lesions were increased in patients infected with an ETB-positive strain. Additional predictors of disease severity and development could be identified. The presence of a staphylococcal plasmid encoding multiple antibiotic resistance traits, as detected by binary typing, was associated with a reduction in the cure rate. Our results recognize that a combination of staphylococcal virulence and resistance genes rather than a single gene determines the development and course of nonbullous impetigo. The identification of these microbial genetic markers, which are predictive of the severity and the course of the disease, will facilitate guided individualized antimicrobial therapy in the future.
非大疱性脓疱病是儿童常见的皮肤感染，通常由金黄色葡萄球菌引起。葡萄球菌毒素尤其是剥脱毒素A是儿童大疱性脓疱病的已知介质。对于非大疱性脓疱病是否也是如此尚不清楚。我们着手分析来自荷兰一个有限地理区域内患有非大疱性脓疱病儿童的金黄色葡萄球菌临床分离株的克隆性。我们调查了葡萄球菌鼻腔携带情况以及葡萄球菌菌株的性质是否与脓疱病的严重程度和病程相关。从患有脓疱病的儿童的鼻子和伤口处获取细菌分离株。通过脉冲场凝胶电泳介导的分型和二元分型对菌株进行基因特征分析，二元分型也用于评估毒素基因含量。此外，每位参与的患者都填写了一份详细的临床问卷。葡萄球菌鼻腔携带似乎使患者易患脓疱病，在鹿特丹地区诊断出的感染中有34%是由一种克隆类型的金黄色葡萄球菌引起的。金黄色葡萄球菌菌株携带剥脱毒素B（ETB）基因作为一种特定的毒力因子。特别是，感染ETB阳性菌株的患者的皮损数量（P = 0.002）和大小（P < 0.001）增加。可以确定疾病严重程度和发展的其他预测因素。通过二元分型检测到的编码多种抗生素耐药性状的葡萄球菌质粒的存在与治愈率降低有关。我们的结果表明，葡萄球菌毒力基因和耐药基因的组合而非单一基因决定了非大疱性脓疱病的发生和病程。识别这些可预测疾病严重程度和病程的微生物遗传标记，将有助于未来指导个体化抗菌治疗。
