Szumlanski Tobias, Neumann Bernd, Bertram Ralph, Simbeck Alexandra, Ziegler Renate, Monecke Stefan, Ehricht Ralf, Schneider-Brachert Wulf, Steinmann Joerg
Institute for Hospital Hygiene, Medical Microbiology and Clinical Infectiology, Paracelsus Medical University, Nuremberg General Hospital, 90419 Nuremberg, Germany.
Department of Surgery, Asklepios Hospital Barmbek, 22307 Hamburg, Germany.
Microorganisms. 2022 Dec 24;11(1):54. doi: 10.3390/microorganisms11010054.
Community-acquired methicillin-resistant strains (CA-MRSA) are spread worldwide and often cause recurring and persistent infections in humans. CA-MRSA strains frequently carry Panton-Valentine leukocidin (PVL) as a distinctive virulence factor. This study investigates the molecular epidemiology, antibiotic resistance and clinical characteristics of PVL-positive MRSA strains in Northern Bavaria, Germany, isolated over an eight-year period.
Strains were identified by MALDI-TOF MS and antibiotic susceptibility was tested by automated microdilution (VITEK 2) or disk diffusion. PVL-encoding genes and were detected by PCR. MRSA clonal complexes (CC) and lineages were assigned by genotyping via DNA microarray and -typing.
In total, 131 PVL-positive MRSA were collected from five hospital sites between 2009 and 2016. Predominant lineages were CC8-MRSA-[IV+ACME], USA300 (27/131; 20.6%); CC30-MRSA-IV, Southwest Pacific Clone (26/131; 19.8%) and CC80-MRSA-IV (25/131; 19.1%). Other CCs were detected less frequently. Resistance against erythromycin and clindamycin was prevalent, whereas all strains were sensitive towards vancomycin and linezolid. In total, 100 cases (76.3%) were causally linked to an infection. The majority (102/131; 77.9%) of isolates were detected in skin swabs or swabs from surgical sites.
During the sample period we found an increase in the PVL-positive MRSA lineages CC30 and CC1. Compared to less-abundant lineages CC1 or CC22, the predominant lineages CC8, CC30 and CC80 harbored a broader resistance spectrum. Furthermore, these lineages are probably associated with a travel and migration background. In the spatio-temporal setting we investigated, these were arguably drivers of diversification and change in the landscape of PVL-positive MRSA.
社区获得性耐甲氧西林菌株（CA-MRSA）在全球范围内传播，常导致人类反复和持续性感染。CA-MRSA菌株常携带杀白细胞素（PVL）作为独特的毒力因子。本研究调查了德国巴伐利亚北部八年间分离出的PVL阳性MRSA菌株的分子流行病学、抗生素耐药性及临床特征。
通过基质辅助激光解吸电离飞行时间质谱（MALDI-TOF MS）鉴定菌株，采用自动微量稀释法（VITEK 2）或纸片扩散法检测抗生素敏感性。通过聚合酶链反应（PCR）检测PVL编码基因。通过DNA微阵列基因分型和 -分型确定MRSA克隆复合体（CC）和谱系。
2009年至2016年期间，共从五个医院地点收集了131株PVL阳性MRSA。主要谱系为CC8-MRSA-[IV+ACME]、USA300（27/131；20.6%）；CC30-MRSA-IV，西南太平洋克隆株（26/131；19.8%）和CC80-MRSA-IV（25/131；19.1%）。其他CCs检出频率较低。对红霉素和克林霉素的耐药性普遍存在，而所有菌株对万古霉素和利奈唑胺敏感。共有100例（76.3%）与感染有因果关系。大多数分离株（102/131；77.9%）在皮肤拭子或手术部位拭子中检出。
在采样期间，我们发现PVL阳性MRSA谱系CC30和CC1有所增加。与不太常见的谱系CC1或CC22相比，主要谱系CC8、CC30和CC80具有更广泛的耐药谱。此外，这些谱系可能与旅行和移民背景有关。在我们调查的时空环境中，这些可以说是PVL阳性MRSA格局多样化和变化的驱动因素。
