感染性心内膜炎51例临床分析

目的分析感染性心内膜炎(IE)患者临床特征及疗效,探讨IE的早期诊断及合理治疗。方法回顾性分析2009年1月1日至2010年10月31日收治的51例IE病例的临床资料,分析IE患者的心脏基础疾病情况、血培养、超声心动图改变及治疗效果、预后等。结果 51例IE患者中以无基础疾病(27.45%)及风湿性瓣膜病变后IE(23.50%)最为多见,感染病原体以葡萄球菌属多见(46.88%,15/32),次为链球菌属(28.12%,9/32)。超声心动图检查阳性率高(80.39%),手术治疗21例(41.18%,21/51),51例中共死亡5例。结论 IE的临床特征发生了明显变化,临床需提高认识,多学科合作,使疾病得到恰当治疗处理。     

Genome-based approaches to develop epitope-driven subunit vaccines against pathogens of infective endocarditis

Infective endocarditis (IE) has emerged as a public health problem due to changes in the etiologic spectrum and due to involvement of resistant bacterial strains with increased virulence. Developing potent vaccine is an important strategy to tackle IE. Complete genome sequences of eight selected pathogens of IE paved the way to design common T-cell driven subunit vaccines. Comparative genomics and subtractive genomic analysis were applied to identify adinosine tri phosphate (ATP)-binding cassette (ABC) transporter ATP-binding protein from Streptococcus mitis (reference organism) as common vaccine target. Reverse vaccinology technique was implemented using computational tools such as ProPred, SYFPEITHI, and Immune epitope database. Twenty-one T-cell epitopes were predicted from ABC transporter ATP-binding protein. Multiple sequence alignment of ABC transporter ATP-binding protein from eight selected IE pathogens was performed to identify six conserved T-cell epitopes. The six selected T-cell epitopes were further evaluated at structure level for HLA-DRB binding through homology modeling and molecular docking analysis using Maestro v9.2. The proposed six T-cell epitopes showed better binding affinity with the selected HLA-DRB alleles. Subsequently, the docking complexes of T-cell epitope and HLA-DRBs were ranked based on XP Gscore. The T-cell epitope (208-LNYITPDVV-216)–HLA-DRB1^?0101 (1T5?W) complex having the best XP Gscore (?13.25?kcal/mol) was assessed for conformational stability and interaction stability through molecular dynamic simulation for 10?ns using Desmond v3.2. The simulation results revealed that the HLA-DRB–epitope complex was stable throughout the simulation time. Thus, the epitope would be ideal candidate for T-cell driven subunit vaccine design against infective endocarditis.     

Characterization of sequential immune complexes in infective endocarditis by Western blot analysis

A patient with cutaneous vasculitis during infective endocarditis due to Lactobacillus casei was studied. Immune complexes (IC) were isolated from serum at the time of diagnosis and after 4 wk of therapy. Purification of IC used differential polyethylene glycol precipitation and competitive binding to staphylococcal protein A. In situ radioiodination of IC was performed, followed by SDS-polyacrylamide gel electrophoresis (PAGE). Anti-IC antisera were raised in rabbits by immunization with purified IC. IC were characterized by SDS-PAGE followed by electrophoretic transfer to nitrocellulose, incubation with antiserum and then with 125I protein A, and autoradiography. Although early and late IC differed quantitatively, there were no differentiating immunochemical features. Both IC contained a 60,000 dalton component that did not react with preimmune serum nor with anti-normal human serum. This component reacted with antiserum rendered specific for L. casei by affinity chromatography. The restricted antigen-antibody representation in IC contrasted with a wider panel of antibody activity in patient serum. The Western blot analysis proves to be an ideal method for the characterization of IC because of its sensitivity, dissociative capability, and preservation of immunoreactivity. IC isolated at a time removed from the original antigenic challenge may provide insight into the nature of the inciting antigen.     

Focal myocardial effects in infective endocarditis

Netherlands Heart Journal -     

Infective endocarditis caused by unusual gram-positive pathogens

Of a total of 81 patients hospitalized in the infectious diseases department in 1990–2000 with infectious endocarditis caused by Gram-positive pathogen, unusual etiological agents were found in several cases:Streptococcus pyogenes, Streptococcus pneumoniae, Corynebacterium diphtheriae, andGemella morbillorum. Cardiac defects were present in the latter two patients: bicuspid aortic valve and tetralogy of Fallot. Two patients were successfully treated with antibiotics only and one patient with antibiotics and surgery. The patient withC. diphtheriae endocarditis died due to progressive sepsis and multiple organ failure.     

Left-sided infective endocarditis caused by Pseudomonas aeruginosa treated medically

Infective endocarditis due to Pseudomonas aeruginosa is a rare clinical condition, difficult to diagnose and associated with high mortality. Herein we present a case of a 51 years old male without history of intravenous drug use or valvular disease, with past medical history of cholecystectomy in the previous month, who presented to the emergency department with fever, gastrointestinal symptoms, and subsequent signs of distant embolization, positive blood cultures for P. aeruginosa and development of multiple complications of the disease. The clinical presentation of infective endocarditis is nonspecific, leading to delayed diagnosis, and preventing early and effective treatment. Valvular replacement is indicated in fungal or P. aeruginosa endocarditis. This case is notable because of the resolution with amikacin combined with meropenem, in a patient with several complications that contraindicated surgery.     

少动鞘氨醇单胞菌致感染性心内膜炎1例

少动鞘氨醇单胞菌(Sphingomonas paucimobilis) 是一种少见的条件致病菌,可引起手术后感染、创伤后腿部溃疡、菌血症、脑膜炎、慢性蜂窝织炎、手术后眼内炎等,未查见累及心瓣膜的报道.本文报道1例由少动鞘氨醇单胞菌所致感染性心内膜炎的病例.该患者为中年男性,因"反复发热2月余"入院.以发热伴左上腹痛为首...     

Identification of novel positive-strand RNA viruses by metagenomic analysis of archaea-dominated Yellowstone hot springs

There are no known RNA viruses that infect Archaea. Filling this gap in our knowledge of viruses will enhance our understanding of the relationships between RNA viruses from the three domains of cellular life and, in particular, could shed light on the origin of the enormous diversity of RNA viruses infecting eukaryotes. We describe here the identification of novel RNA viral genome segments from high-temperature acidic hot springs in Yellowstone National Park in the United States. These hot springs harbor low-complexity cellular communities dominated by several species of hyperthermophilic Archaea. A viral metagenomics approach was taken to assemble segments of these RNA virus genomes from viral populations isolated directly from hot spring samples. Analysis of these RNA metagenomes demonstrated unique gene content that is not generally related to known RNA viruses of Bacteria and Eukarya. However, genes for RNA-dependent RNA polymerase (RdRp), a hallmark of positive-strand RNA viruses, were identified in two contigs. One of these contigs is approximately 5,600 nucleotides in length and encodes a polyprotein that also contains a region homologous to the capsid protein of nodaviruses, tetraviruses, and birnaviruses. Phylogenetic analyses of the RdRps encoded in these contigs indicate that the putative archaeal viruses form a unique group that is distinct from the RdRps of RNA viruses of Eukarya and Bacteria. Collectively, our findings suggest the existence of novel positive-strand RNA viruses that probably replicate in hyperthermophilic archaeal hosts and are highly divergent from RNA viruses that infect eukaryotes and even more distant from known bacterial RNA viruses. These positive-strand RNA viruses might be direct ancestors of RNA viruses of eukaryotes.     

Enzyme production by lactobacilli and the potential link with infective endocarditis

H.J. OAKEY, D.W.S. HARTY AND K.W. KNOX. 1995. Fifty-six strains of lactobacilli were examined for the production of glycosidases and proteases (arylamidases) that could be associated with the ability to grow in vivo and/or be a factor in the pathogenesis of endocarditis. The strains were from seven species, with an emphasis on Lactobacillus rhamnosus and Lact. paracasei subsp. paracasei , both of which have been associated with endocarditis and provided 12 of the 13 strains isolated from cases of the disease. Other species were Lact. acidophilus, Lact. plantarum, Lact. salivarius, Lact. fermentum and Lact. oris.
Commonly expressed glycosidase activities were α-D-galactosidase and β- N -acetyl-D-glucosaminidase followed by β-D-glucosidase and α-L-fucosidase. The combined production of β- N -acetyl-D-glucosaminidase and α-D-galactosidase was a feature of the endocarditis isolates. In contrast, β-D-galactosidase was produced by very few of the strains within species implicated in endocarditis but most of the strains of Lact. salivarius, Lact. fermentum and Lact. oris.
The most commonly produced arylamidases active against substrates employed for testing human blood clotting cascade were activated protein C(Ca)-like, activated factor X(Xa)-like and Hageman factor-like followed by kallikrein-like and chymotrypsin-like enzymes. Kallikrein-like enzyme activity was shown more frequently by strains from species commonly isolated from cases of endocarditis ( Lact. rhamnosus and Lact. paracasei subsp. paracasei ) than from other oral species ( Lact. plantarum, Lact. salivarius, Lact. fermentum and Lact. oris ).
The data indicate that some lactobacilli can produce enzymes that would enable the breakdown of human glycoproteins and the synthesis and lysis of human fibrin clots, characteristics which aid the colonization and survival of bacteria infecting an endocarditis vegetation.     

Surgical treatment of transcatheter aortic valve infective endocarditis

Netherlands Heart Journal - There is growing interest in infections occurring after transcatheter aortic valve implantation (TAVI). The incidence, and clinical and anatomical features suggest many...     

里昂葡萄球菌致感染性心内膜炎的临床分析

目的:探讨里昂葡萄球菌对感染性心内膜炎的临床特点及其菌株鉴定的要点.方法:对21例感染性心内膜炎患者的临床特征及血液中分离的菌株鉴定与药敏试验作一回顾性分析.结果:患者不规则发热,均从血液中分离出里昂葡萄球菌.菌株鉴定的特征是玻片法凝固酶试验阳性,试管法凝固酶试验阴性;鸟氨酸脱羧酶阳性;对青霉素类药物敏感,不产生β-内酰胺酶.结论:腹股沟、会阴及腋窝等处的手术切口是里昂葡萄球菌感染的适宜部位,由该菌引起的心内膜炎并发症与金黄色葡萄球菌有类似的致病力,在菌株的鉴定与鉴别上应引起重视.     

Surgical treatment of infective endocarditis with special reference to prosthetic valve endocarditis.

Patients with native valve endocarditis treated surgically between 1968 and 1978 (n = 15) and all patients presenting with prosthetic valve endocarditis during this period (n = 21) were followed up for at least four years. Five of the patients with native valve endocarditis required urgent early surgical intervention, of whom two died. The remaining 10 underwent valve replacement after a course of antibiotic treatment: all survived, though one required further valve replacement. The 21 patients with prosthetic valve endocarditis suffered 25 attacks. Nine were cured by medical treatment alone; two died before surgical intervention was possible; 11 required valve replacement, of whom three died; and two required valve replacement after a course of antibiotic treatment. The incidence of early prosthetic valve endocarditis--that occurring within two months of operation--was 0.67%, but that of late prosthetic valve endocarditis could not be determined. Medical treatment when started early should cure endocarditis in most patients, but vigilance should be maintained for the appearance of indications for surgery. When such indications exist surgery should not be delayed.     

静脉毒瘾者金黄色葡萄球菌性感染性右心内膜炎(附2例报告及文献复习)

本文在国内首次报道２例静脉毒瘾者金黄色葡萄球菌性感染性右心内膜炎（ＳＩＲＥＤ）,其临床特点：①常合并有肝炎病毒感染;②确诊有赖于心脏超声检查发现三尖瓣赘生物、细菌的毒血症状及血培养的结果;③治疗应根据药敏结果选择２至３种敏感的抗生素联用,其剂量应比常规量大２至３倍,疗程６至８周或更长;④有效治疗后,该病预后良好