1例白血病患者血液中检出非O1非O139群霍乱弧菌

2012年8月,浦东新区儿童医学中心从1名6岁急性淋巴细胞性白血病复发患儿血液中分离到霍乱弧菌,随后浦东新区疾病预防控制中心对该分离株进行了系统生化鉴定、毒力基因及药物敏感性检测,结果为不产霍乱毒素的非O1非O139霍乱弧菌。     

Vibrio cholerae (non-O1, non-O139) sepsis in a child with Fanconi anemia

A 9-year-old female child who was a known case of Fanconi anemia was admitted to hospital because of fever and gastrointestinal symptoms. Blood culture at the time of admission yielded growth of Gram-negative curved rod that was identified as Vibrio cholerae (non-O1, non-O139), whereas repeated fecal cultures were negative for enteropathogens. To our knowledge, this is the first case of V. cholerae (non-O1, non-O139) septicemia associated with Fanconi anemia.     

非O1/O139群霍乱弧菌:流行、致病因子和耐药

非O1/O139群霍乱弧菌引起的腹泻在许多发展中国家都有发生,其流行涉及到多个血清群。在有些地方,非O1/O139群霍乱弧菌腹泻的发病率甚至超过了O1/O139群霍乱弧菌腹泻的发病率。非O1/O139群霍乱弧菌的致病因子多种多样,肠毒素、蛋白酶、溶血素和三型分泌系统等被认为是重要的致病因子,但其致病机制非常复杂,至今仍然不完全清楚。随着抗生素使用的增加,出现了许多耐药甚至多重耐药菌株。本研究从非O1/O139群霍乱弧菌腹泻的流行情况、致病因子以及耐药方面加以综述。     

Spontaneous bacterial empyema due to non-O1, non-O139 Vibrio cholerae in a cirrhotic patient with hepatocellular carcinoma

Vibrio cholerae is known as a common etiology of epidemic diarrheal disease and rarely causes extra-intestinal infections. In this report, we described a cirrhotic patient with hepatocellular carcinoma who developed spontaneous bacterial empyema due to non-O1, non-O139 V. cholerae. The patient was successfully treated with antimicrobial agents and percutaneous drainage.     

New carbenicillin-hydrolyzing beta-lactamase (CARB-7) from Vibrio cholerae non-O1, non-O139 strains encoded by the VCR region of the V. cholerae genome

In a previous study, an analysis of 77 ampicillin-nonsusceptible (resistant plus intermediate categories) strains of Vibrio cholerae non-O1, non-O139, isolated from aquatic environment and diarrheal stool, showed that all of them produced a beta-lactamase with a pI of 5.4. Hybridization or amplification by PCR with a probe for bla(TEM) or primers for bla(CARB) gene families was negative. In this work, an environmental ampicillin-resistant strain from this sample, ME11762, isolated from a waterway in the west region of Argentina, was studied. The nucleotide sequence of the structural gene of the beta-lactamase was determined by bidirectional sequencing of a Sau3AI fragment belonging to this isolate. The gene encodes a new 288-amino-acid protein, designated CARB-7, that shares 88.5% homology with the CARB-6 enzyme; an overall 83.2% homology with PSE-4, PSE-1, CARB-3, and the Proteus mirabilis N29 enzymes; and 79% homology with CARB-4 enzyme. The gene for this beta-lactamase could not be transferred to Escherichia coli by conjugation. The nucleotide sequence of the flanking regions of the bla(CARB-7) gene showed the occurrence of three 123-bp V. cholerae repeated sequences, all of which were found outside the predicted open reading frame. The upstream fragment of the bla(CARB-7) gene shared 93% identity with a locus situated inside V. cholerae's chromosome 2. These results strongly suggest the chromosomal location of the bla(CARB-7) gene, making this the first communication of a beta-lactamase gene located on the VCR island of the V. cholerae genome.     

CARB-9, a carbenicillinase encoded in the VCR region of Vibrio cholerae non-O1, non-O139 belongs to a family of cassette-encoded beta-lactamases

The gene bla(CARB-9) was located in the Vibrio cholerae super-integron, but in a different location relative to bla(CARB-7). CARB-9 (pI 5.2) conferred beta-lactam MICs four to eight times lower than those conferred by CARB-7, differing at Ambler's positions V97I, L124F, and T228K. Comparison of the genetic environments of all reported bla(CARB) genes indicated that the CARB enzymes constitute a family of cassette-encoded beta-lactamases.     

广州市一起非O1/O139群霍乱弧菌食物中毒分离株的病原特征分析

目的 了解2014年广州市某工厂发生的一起非O1/O139群霍乱弧菌食物中毒分离株的耐药特性及分子特征。方法 对分离到的6株非O1/O139群分离株进行生化鉴定、血清学鉴定、药物敏感性实验、毒力相关基因检测和脉冲场凝胶电泳（PFGE）分子分型分析。结果 6株分离株经生化鉴定、血清学鉴定为非O1/O139群。药物敏感性分析显示,6株分离株均对氨苄西林、头孢克肟、头孢拉定、阿米卡星、妥布霉素、庆大霉素和多粘菌素B耐药,对诺氟沙星、环丙沙星、复方新诺明、呋喃唑酮、四环素、吡哌酸、红霉素和氯霉素敏感。毒力基因聚合酶链反应检测结果显示,所有菌株均携带毒力表达调控基因（toxR）和溶血素基因（hlyA）,未检出霍乱肠毒素基因（ctxA）、毒力协同调节菌毛基因（tcpA）和肠毒素基因（ST）;5株病例分离株和1株冷柜内壁分离株经限制性内切酶NotⅠ消化后的PFGE图谱为同一型别。结论 此次食物中毒的病原体为非O1/O139群霍乱弧菌,具有共同的遗传特征,菌株出现了多重耐药,提示应加强该类菌株的监测,防止大范围扩散或暴发流行。     

一起引起食物中毒的非O1群霍乱弧菌实验室鉴定

目的 查明引发浙江省宁波市某服饰公司食物中毒事件的病原菌.方法 对采集到可疑食品和肛拭等标本参照GB/T4789-2003标准进行细菌的分离、鉴定及血清学分型;参照霍乱防治手册检测菌株的CT毒力基因.结果 6份患者大便标本与14份轻微腹泻患者或腹部不适者大便标本中检出非O1群霍乱弧菌O29血清型9株,其中腹泻患者标本检出6株,轻微腹泻患者中检出3株,检出率为45.0%.未检出志贺菌、副溶血性弧菌、致病性大肠杆菌、O1群和O139霍乱弧菌、金黄色葡萄球菌等致病菌,剩余食物未检出志贺菌、副溶血性弧菌、致病性大肠杆菌、O1群和O139霍乱弧菌、金黄色葡萄球菌等致病菌.结论 此次食物中毒为非O1群霍乱弧菌O29血清型所致.     

一起O139霍乱暴发的传染来源分析

目的 对一起霍乱暴发疫情中来自患者和甲鱼的O139群霍乱菌株分离株分子特征分析,判断传染来源.方法 对疫情调查中的3株患者分离株和3株来自水产市场甲鱼标本的分离株,采用聚合酶链反应(PCR)检测分离菌株的毒力相关基因(ctxAB、toxR、zot);用脉冲场凝胶电泳技术(PFGE)对菌株进行分子分型,所得结果以Bio-Numeric V 4.0软件进行聚类分析.结果 6株菌所有毒力相关基因全部阳性,均为产毒株.6株菌可得2个PFGE型,其中2株甲鱼株与3株患者株带型相同,1株甲鱼株独立成型.通过Pulse Net China数据库搜索,6株菌与中国某省O139群霍乱弧菌聚餐暴发菌株分子分型不同.结论 此次霍乱暴发疫情中甲鱼为可能的传染来源,提示该地区在今后霍乱防治工作中,应注意以甲鱼为重点的水产品的安全.     

Bacteremic cellulitis caused by Non-01, Non-0139 Vibrio cholerae: report of a case in a patient with hemochromatosis

We report a case of bacteremia associated with hemorrhagic bullous skin lesions on the leg caused by non-01, non-0139 Vibrio cholerae in a 66-year-old man with hemochromatosis developed in an inland region. The organism was isolated from blood and bullae fluid. The patient was treated successfully with cefotaxime and doxycycline. This report emphasizes the potential of this organism to produce bacteremic cellulitis in people with underlying illness in the absence of usual epidemiological risk factors.     

Molecular Characterization of ISCR1-Mediated blaPER-1 in a Non-O1, Non-O139 Vibrio cholerae Strain from China

We report the detection of PER-1 extended-spectrum β-lactamase (ESBL) in a clinical non-O1, non-O139 Vibrio cholerae strain from China. ISCR1-mediated bla_PER-1 was embedded in a complex In4 family class 1 integron belonging to the lineage of Tn1696 on a conjugative IncA/C plasmid. A free 8.98-kb circular molecule present with the ISCR1-bla_PER-1–truncated 3′-conserved sequence (CS) structure was detected in this isolate. These findings may provide insight into the mobilization of bla_PER-1.     

Occurrence of antibiotic resistance gene cassettes aac(6')-Ib,dfrA5, dfrA12, and ereA2 in class I integrons in non-O1, non-O139 Vibrio cholerae strains in India

Molecular mechanisms of multidrug resistance in Vibrio cholerae belonging to non-O1, non-O139 serogroups isolated during 1997 to 1998 in Calcutta, India, were investigated. Out of the 94 strains examined, 22 strains were found to have class I integrons. The gene cassettes identified were dfrA1, dfrA15, dfrA5, and dfrA12 for trimethoprim; aac(6')-Ib for amikacin and tobramycin; aadA1 and aadA2 for streptomycin and spectinomycin; and ereA2 for erythromycin resistance. To our knowledge, this is the first report of the presence of dfrA5, dfrA12, aac(6')-Ib, and ereA2 cassettes in class I integrons of V. cholerae. Forty-three of 94 strains also had plasmids, and out of these, 14 contained both class I integrons and plasmids. Pulsed-field gel electrophoresis followed by Southern hybridization revealed that in the 14 plasmid-bearing strains, class I integrons resided either on chromosomes, on plasmids, or on both. Our results indicated that besides class I integrons and plasmids, a conjugative transposon element, SXT, possibly contributed to the multiple antibiotic resistance.     

Identification of Vibrio cholerae serogroups O1 and O139 by monoclonal antibodies in the slide agglutination test

The agglutinating properties of MCA-O1 of the IgG class and MCA-O139 of the IgM class towards epitopes of O-antigen of Vibrio cholerae O1 and accordingly Vibrio cholerae O139 were studied. The ascitic and cultural fluids by hybridomas F8G12 and D11 deposited in the specialized Collection of Cell Cultures of Vertebrates (Saint Petersburg) under RKKK (II) 386 D and RKKK (II) 674 D were the sources of monoclonal immunoglobulins. The advantage of diagnostic monoclonal immunoglobulins is that they are distinguished for strict specificity and their use in practical health care contributes to the higher specificity of a laboratory test for cholera and to its shorter performance.     

浙江省丽水市首起非O1群霍乱弧菌食物中毒分子生物学溯源分析

目的 利用分子生物技术了解引起食物中毒的非O1群霍乱弧菌携带毒力基因情况及耐药性特征.方法 对检出的非O1群霍乱弧菌菌株进行耐药性分析,同时采用聚合酶链反应(PCR)方法进行霍乱弧菌肠毒素基因(Ctx)、小带联结毒素基因(Zot)、辅助霍乱肠毒素(Ace)基因的检测,并参照美国CDC PulseNet的统一方法进行脉冲场凝胶电泳(PFGE)分型并作同源性分析.结果 从8例患者和8份食品标本中分离到7株非O1群霍乱弧菌,未检出Ctx、Zot、Ace等毒素基因,检出溶血素,Dienes试验和脉冲场凝胶电泳图谱显示病人分离株和剩余食物检出株同源.经耐药性分析,菌株除对复方新诺明、氨苄西林100%耐药外,对其余抗生素均较敏感.结论 通过实验证实本次食物中毒是由聚餐者共同食用冷菜凤爪所致,流行病学追溯从患者共同食用冷菜和海产品中非O1群霍乱弧菌毒力基因、耐药性和脉冲场凝胶电泳分析为同源菌株.     

Non-O1 Vibrio cholerae septicemia: case report, discussion of literature, and relevance to bioterrorism

With emerging resistance to fluoroquinolones, there arises a need to establish quality control (QC) guidelines for doxycycline, an effective alternative for treating various community-acquired respiratory tract infections. This multicenter study was performed to establish QC guidelines for susceptibility testing those Gram-positive QC organisms against doxycycline. The proposed three or four log₂ dilution MIC ranges included 100.0% of the doxycycline MIC values reported.     

PD-1抑制剂致胰岛β细胞功能急剧丧失后糖尿病2例报告

本文报道2例程序性死亡受体1(programmed death-1,PD-1)抑制剂导致的1型糖尿病。一例患者为53岁男性,因食管癌接受信迪利单抗联合艾越奈达铂治疗,使用6个周期后突然出现糖尿病酮症酸中毒；另一例为46岁女性,因恶性黑色素瘤接受卡瑞利珠单抗治疗14次后随访血糖过程中出现血糖明显升高,及时给予治疗。这2例患者空腹及葡萄糖负荷后血清Ｃ肽均处于极低水平,糖尿病相关抗体及自身抗体阴性,提示胰岛β细胞完全丧失。这两例患者均诊断为PD-1抑制剂相关1型糖尿病,需要长期餐时胰岛素及长效胰岛素强化治疗；但一例治疗过程中未随访血糖,突然以糖尿病酮症酸中毒起病；一例治疗中随访血糖,发现血糖高及时治疗,避免出现糖尿病急性并发症。因此对于使用PD-1抑制剂治疗的患者需要定期监测患者的血糖,及时发现血糖升高,给予相应治疗,避免出现严重并发症。     

Varied clinical presentations of Vibrio vulnificus infections: a report of four unusual cases and review of the literature

Vibrio vulnificus is a Gram-negative, motile, curved bacillus of the family Vibrionaceae that is a rare cause of gastroenteritis, septicemia, and wound infections in humans. V. vulnificus is halophilic, flourishes in warm temperatures, and is part of the bacterial flora of the marine environment. The location of our health care setting, on the Gulf of Mexico, has given us the opportunity to observe a wide variety of clinical presentations of infections caused by this organism. In the first case, a 27-year-old man struck by lightning while windsurfing was found pulseless in the water and was resuscitated. The patient subsequently developed cardiac arrhythmias, respiratory failure, and necrotizing fasciitis, blood cultures yielded V. vulnificus. After antibiotic therapy and several fasciotomies, the patient recovered. The second case was that of a 43-year-old Asian man employed as an oyster shucker who presented with complaints of redness, tearing, and photophobia of the right eye. The diagnosis of corneal ulcer secondary to V. vulnificus was made after culture of the right eye revealed the organism. The third case involved a 46-year-old man who presented with complaints of abdominal pain, nausea, chills, and bullous lesions on the lower extremities. He developed disseminated intravascular coagulation, and cultures of the lesions on his lower extremities showed V. vulnificus. Initially, the patient denied any exposure to raw seafood or seawater, but he eventually remembered eating raw oysters 3 days before his illness. The fourth case is that of a 32-year-old, human immunodeficiency virus-positive, hepatitis C-positive woman with cirrhosis who presented with productive cough, chills, fever, and red spots on her extremities and buttocks. Blood cultures revealed V. vulnificus and the patient was treated with antibiotics and improved clinically. These four cases illustrate the wide range of clinical presentations associated with this organism.     

Novel PCR-based genotyping method,using genomic variability between repetitive sequences of toxigenic Vibrio cholerae O1 El Tor and O139

A novel genotyping method for toxigenic Vibrio cholerae O1 El Tor and O139 was developed. The method was designed to amplify DNA sequences “sandwiched“ between any given pair of repetitive sequences, “V. cholera repeats (VCR)”, in highly polymorphic “integron island” of ca. 125 kb in the small chromosome of toxigenic V. cholerae so that the resultant PCR amplicons would present with a strain-specific electrophoretic pattern. The VCR-targeted PCR assay (VCR-PCR) for 37 strains of toxigenic V. cholerae O1 El Tor and O139 revealed that the O1 strains isolated before 1990 showed distinct clonality whereas those isolated after 1990 could be separated into two clones, one consisting of strains isolated from South American countries and another of those from other countries. By contrast, O139 strains were genotypically homogenous regardless of the geographic origin or time of isolation. VCR-PCR therefore would be a robust but rapid method for genotypic differentiation of toxigenic V. cholerae O1 El Tor and O139 strains and to recognize strains with epidemic potential.     

Clinical and laboratory features of an outbreak of Vibrio cholerae O1 infections in the United States

A point source outbreak of Vibrio cholerae O1 El Tor Inaba infections occurred aboard an oil rig south of Port Arthur, Texas, in September 1981. Sixteen crew members had V. cholerae O1 infections as determined by serology or stool specimens; 15 were symptomatic. The high percentage of symptomatic infections was attributed in part to the ingestion of a large number of V. cholerae O1 organisms by susceptible individuals. Symptoms included diarrheal stools (100%), weakness (60%), abdominal cramps (53%), nausea (40%), and vomiting (27%). Only one of the three patients who sought medical attention was diagnosed by his physician as having cholera. Physicians who treat patients who live near or travel to the Gulf Coast should consider cholera in patients with watery stools. If cholera is suspected, laboratories should use thiosulfate-citrate-bile salts-sucrose (TCBS) agar in addition to routine enteric media for processing stool specimens.