VITEK 2 Compact联合MALDI-TOF MS、16S rDNA基因测序对1株类志贺邻单胞菌的对比鉴定报告

Comparative identification report of a strain of P.shigella by VITEK 2 Compact,MALDI-TOF MS and 16S rDNA gene sequencing

类志贺邻单胞菌属于肠杆菌科的邻单胞菌属,是革兰阴性杆菌,为人类条件致病菌,该菌首先发现于胃肠道,但无明确证据证实其具有肠致病性,仅个别例证报道其可引起败血症和肠胃炎。霍乱弧菌属于弧菌属,革兰阴性杆菌,血清型O1群和O139群是甲类传染病霍乱的病原菌,通过侵袭力和霍乱肠毒素致病,可引起严重的呕吐和腹泻;而血清型非O1/O139群血流感染在国内偶见报道。本文报告1例在湘潭市中心医院就诊的慢性肝病患者无明显诱因出现腹痛、腹泻伴呕吐,且畏寒、寒战,血培养检出1株革兰阴性杆菌,初期经VITEK 2 Compact全自动细菌鉴定及药敏分析系统鉴定为霍乱弧菌;但后经基质辅助激光解析电离飞行时间质谱技术(matrix-assisted laser desorption/ionization time-of-flight mass spectrometry,MALDI-TOF MS)和16S rDNA基因测序,均确认为类志贺邻单胞菌。根据药敏试验结果,予哌拉西林/他唑巴坦抗感染,输血、护肝等对症治疗后好转出院,随访无复发。本报告结果提示,当Vitek-2 Compact将待检样本鉴定为霍乱弧菌等临床少见菌时,仍须结合细菌菌落形态、辅助生化试验以及患者的临床情况进行综合判断,必要时可采用质谱、基因测序等其他检测手段进行复核。

Plesiomonas shigelloides belongs to the genus Orthomonas of Enterobacteriaceae.It is a gram-negative bacterium and opportunistic pathogens of human beings.It was firstly found in the gastrointestinal tract,but there was no clear evidence that it was enteropathogenic,and only a few cases supported that it could cause sepsis and gastroenteritis.Vibrio cholerae is a gram-negative bacterium belonging to Vibrio.Serotypes O1 and O139 are the pathogenic bacteria of class A infectious diseases of cholera.They can cause severe vomiting and diarrhea by invasiveness and cholera enterotoxin.Blood flow infection of serotype non-O1/O139 group is occasionally reported in China.This patient was with chronic liver disease.There was no obvious inducement for abdominal pain,diarrhea and vomiting.Blood was collected for culture when they were afraid of cold and shivering.A gram-negative bacilli was detected and identified as Vibrio cholerae by VITEK 2 compact automatic bacterial identification and drug sensitivity analysis system.After qualitative analysis and 16S rDNA gene sequencing,the patient was confirmed to be infected with plesiomonas shigelloides.According to the results of drug sensitivity test,piperacillin/tazobactam was given for anti infection.After symptomatic treatment of blood transfusion and liver protection,the patient was discharged from hospital with no recurrence.The results of this report suggest that when vibrio cholerae and other clinically rare bacteria are identified by vitEK-2 Compact,a comprehensive judgment should be made based on bacterial colony morphology,auxiliary biochemical tests and clinical conditions of patients.If necessary,mass spectrometry,gene sequencing and other detection methods can be used for rechecking.