College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Sichuan, China.
Yalong River Hydropower Development Company Ltd., Chengdu, Sichuan, China.
Transbound Emerg Dis. 2018 Dec;65(6):1816-1822. doi: 10.1111/tbed.12957. Epub 2018 Sep 21.
Acinetobacter lwoffii, a serious human pathogen, has been identified as a cause of nosocomial infections such as bacteremia, pneumonia and meningitis. There are only a few studies reporting A. lwoffii as a pathogen of fish. During 2016 and 2017, six bacterial strains, isolated from diseased fish of the Schizothorax genus, were identified as A. lwoffii by morphology, biochemical tests, 16S rDNA and gyrB gene sequencing analysis. One of these isolates was selected for experimental infection of Sclizothorax prenanti, Schizothorax davidi and Schizothorax wangchiachii, to confirm its pathogenicity. Experimentally infected fish showed similar symptoms to those observed in fish after natural outbreaks. Susceptibility of the isolates to 14 antibiotics was tested using a disc diffusion method; all isolates were resistant to cephalothin, aminoglycosides and β-lactams, and sensitive only to some fluoroquinolones and tetracyclines. Histological examination revealed that A. lwoffii infection could cause pathological lesions in multiple organs and tissues, especially in liver, kidney, spleen and heart. These lesions included extensive haemorrhage, vacuolar degeneration, necrosis and inflammatory cell infiltration. To our knowledge, this is the first report on A. lwoffii as a virulent pathogen for fish of the Schizothorax genus.
鲁氏不动杆菌是一种严重的人类病原体，已被确定为医院感染的病因，如菌血症、肺炎和脑膜炎。仅有少数研究报告将 A. lwoffii 作为鱼类病原体。2016 年至 2017 年，从患病的裂腹鱼属鱼类中分离出的 6 株细菌，通过形态学、生化试验、16S rDNA 和 gyrB 基因测序分析鉴定为 A. lwoffii。从中选择一株进行实验感染齐口裂腹鱼、大理裂腹鱼和硬刺松潘裂腹鱼，以确认其致病性。实验感染的鱼类表现出与自然暴发后鱼类相似的症状。采用纸片扩散法检测分离株对 14 种抗生素的敏感性；所有分离株均对头孢菌素、氨基糖苷类和β-内酰胺类抗生素耐药，仅对一些氟喹诺酮类和四环素类药物敏感。组织学检查显示，A. lwoffii 感染可导致多个器官和组织的病理损伤，特别是肝脏、肾脏、脾脏和心脏。这些病变包括广泛出血、空泡变性、坏死和炎症细胞浸润。据我们所知，这是首次报道 A. lwoffii 是裂腹鱼属鱼类的一种强毒病原体。
