Friedrich Loeffler-Institute of Medical Microbiology, University Medicine Greifswald, Greifswald, Germany.
Department of Epidemiology and Ecology of Antimicrobial Resistance, Helmholtz Institute for One Health, Helmholtz Centre for Infection Research Helmholtz Center for Infection Research (HZI), Greifswald, Germany.
Front Cell Infect Microbiol. 2024 Mar 27;14:1372704. doi: 10.3389/fcimb.2024.1372704. eCollection 2024.
In this study, we characterized a strain in a patient with shrapnel hip injury, which resulted in multiple phenotypic changes, including the formation of a small colony variant (SCV) phenotype. Although already described since the 1960s, there is little knowledge about SCV phenotypes in . The formation of SCVs has been recognized as a bacterial strategy to evade host immune responses and compromise the efficacy of antimicrobial therapies, leading to persistent and recurrent courses of infections. In this case, 14 isolates with different resisto- and morpho-types were distinguished from the patient's urine and tissue samples. Whole genome sequencing revealed that all isolates were clonally identical belonging to the high-risk sequence type 147. Subculturing the SCV colonies consistently resulted in the reappearance of the initial SCV phenotype and three stable normal-sized phenotypes with distinct morphological characteristics. Additionally, an increase in resistance was observed over time in isolates that shared the same colony appearance. Our findings highlight the complexity of bacterial behavior by revealing a case of phenotypic "hyper-splitting" in a SCV and its potential clinical significance.
在这项研究中，我们对一名弹片髋部损伤患者携带的一株 进行了特征描述，该患者发生了多种表型变化，包括形成小菌落变异（SCV）表型。尽管自 20 世纪 60 年代以来已经有相关描述，但我们对 中的 SCV 表型知之甚少。SCV 的形成已被认为是细菌逃避宿主免疫反应和降低抗菌治疗效果的策略，导致持续和反复的感染过程。在本例中，从患者的尿液和组织样本中分离出 14 株具有不同耐药性和形态学特征的分离株。全基因组测序显示，所有分离株均为克隆相同，属于高风险序列型 147。对 SCV 菌落进行继代培养会持续重现初始 SCV 表型，以及三种具有明显形态特征的稳定正常大小的表型。此外，具有相同菌落外观的分离株的耐药性随着时间的推移而增加。我们的研究结果突显了细菌行为的复杂性，揭示了 中表型“超分裂”的一个案例及其潜在的临床意义。
