海南省一例足部皮肤感染海藻施万菌的鉴定分析

Identification and analysis of a case of foot skin infection with Schwanella algae in Hainan Province

目的本研究对2022年5月海南省1例足部皮肤感染患者伤口分泌物分离培养的菌株进行鉴定并分析其耐药基因和药物敏感性。方法采用革兰染色方法,VITEK 2 Compat和MALDI-TOF MS质谱检测系统对分离株进行鉴定,并通过16S rRNA、gyrB基因序列和ANI进行溯源分析,同时采用肉汤稀释法开展药敏试验并进行耐药基因检测。结果该分离株镜检为革兰氏阴性杆菌,VITEK 2 Compat和MALDI-TOF MS质谱检测系统鉴定结果为海藻施万菌,鉴于临床鉴定系统有一定的局限性,因此进一步基于基因水平对其16S rRNA序列、gyrB保守基因和全基因组序列进行比对分析,最终溯源分析该菌株为海藻施万菌。结论海藻施万菌的鉴定需要临床鉴定系统结合基因水平的分子生物学方法进行,该研究首次在我国海南岛的临床病例中鉴定到1株海藻施万菌,为临床微生物实验室准确鉴定罕见人兽共患病病原菌提供了较为全面的方法学参考,同时提示海南地区临床工作人员要加强对施万菌引起的临床感染的认识和监测。

Objective To isolate a strain of Shewanella algae from wound secretion culture of a patient with foot skin infection in Hainan Province in May 2022 and to analyze its antimicrobial resistance related genes and antimicrobial susceptibility.Methods A strain of Shewanella algae was isolated from a patient with foot skin infection,identified by Gram staining,VITEK 2 Compat,and matrix-assisted laser desorption ionization-time of flight mass spectrometry,and analyzed by 16S rRNA sequencing,gyrB gene sequencing,and average nucleotide identity.The antimicrobial susceptibility test and detection of resistance related genes were then carried out.Results Microscopic examination of the isolate revealed a Gram-negative bacillus.Since the clinical identification system has certain limitations,the 16S rRNA sequence,gyrB gene sequence,and whole genome sequence were analyzed.Finally,the strain was determined to be Shewanella algae.Conclusion The clinical identification system combined with molecular biology methods are required for Shewanella algae identification.This study was the first to identify a strain of Shewanella algae in a clinical case on Hainan Island in China,which provides a comprehensive methodological reference for clinical microbiology laboratories to accurately identify rare zoonotic pathogens,and clinical staff in Hainan should strengthen the understanding and monitoring of clinical infection caused by Shewanella.