Aeromonas Species in Septicemia: Laboratory Characteristics and Clinical Observations

Janda, J. Michael; Guthertz, Linda S.; Kokka, Robert; Shimada, Toshio

doi:10.1093/clinids/19.1.77

Cited by 152 publications

(118 citation statements)

References 20 publications

Supporting

Mentioning

109

Contrasting

Unclassified

Order By: Relevance

“…The case fatality rates among patients with Aeromonas bacteremia in the literature range from 28% -63% (4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(44)(45)(46)(47)(48). In the present study, the case fatality rate was 33% in the patients with monomicrobial Aeromonas bacteremia and 31% in polymicrobial Aeromonas bacteremia.…”

Section: Discussionsupporting

confidence: 41%

Different Clinical Characteristics between Polymicrobial and Monomicrobial Aeromonas Bacteremia -A Study of 216 Cases

Lay

Zhuang

et al. 2010

Intern. Med.

View full text Add to dashboard Cite

Background Part of Aeromonas bacteremia is polymicrobial infection. However, a clinical comparison of monomicrobial and polymicrobial Aeromonas bacteremia has not hitherto been reported. Methods A retrospective analysis of medical records of patients with Aeromonas bacteremia at three large referral hospitals in Taiwan for an 8-year period (2001-2008) was conducted. Results There were 154 patients with monomicrobial Aeromonas bacteremia and 62 patients with polymicrobial Aeromonas bacteremia. In the polymicrobial infections, E. coli was the most common combined pathogen (42%), followed by Klebsiella spp. (24%) and Enterobacter spp. (16%). Multivariate logistic regression analysis revealed solid cancer as the risk factor for polymicrobial Aeromonas bacteremia, with male gender and cirrhosis as risk factors for monomicrobial Aeromonas bacteremia. However, of all types of solid cancer, hepatoma was associated with monomicrobial Aeromonas bacteremia. APACHE II score was the most important prognostic factor in both groups. Conclusion Aeromonas bacteremia in patients with cirrhosis or male gender tended to be monomicrobial. Polymicrobial Aeromonas bacteremia was associated with solid cancers. In either polymicrobial or monomicrobial Aeromonas bacteremia, prognosis could be predicted according to disease severity measured by APACHE II score.

show abstract

Section: Discussionsupporting

confidence: 41%

Different Clinical Characteristics between Polymicrobial and Monomicrobial Aeromonas Bacteremia -A Study of 216 Cases

Lay

Zhuang

et al. 2010

Intern. Med.

View full text Add to dashboard Cite

show abstract

“…Some strains of A. hydrophila are also reported to cause infections in humans. The clinical symptoms include septicemia (17), meningitis (25), peritonitis (35), pneumonia (32), myonecrosis (34), and diarrhea (21). The genus Aeromonas has been classified into 96 serogroups (50,60), and a role for surface polysaccharides in the pathogenicity of certain A. hydrophila strains has been proposed.…”

mentioning

confidence: 99%

NovelAeromonas hydrophilaPPD134/91 Genes Involved in O-Antigen and Capsule Biosynthesis

Zhang¹,

Arakawa

Leung

2002

Infect Immun

View full text Add to dashboard Cite

The sequences of the O-antigen and capsule gene clusters of the virulent Aeromonas hydrophila strain PPD134/91 were determined. The O-antigen gene cluster is 17,296 bp long and comprises 17 genes. Seven pathway genes for the synthesis of rhamnose and mannose, six transferase genes, one O unit flippase gene, and one O-antigen chain length determinant gene were identified by amino acid sequence similarity. PCR and Southern blot analysis were performed to survey the distribution of these 17 genes among 11 A. hydrophila strains of different serotypes. A. hydrophila PPD134/91 might belong to serotype O:18, as represented by JCM3980; it contained all the same O-antigen genes as JCM3980 (97 to 100% similarity at the DNA and amino acid levels). The capsule gene cluster of A. hydrophila PPD134/91 is 17,562 bp long and includes 13 genes, which were assembled into three distinct regions similar to those of the group II capsule gene cluster of Escherichia coli and other bacteria. Regions I and III contained four and two capsule transport genes, respectively. Region II had five genes which were highly similar to capsule synthesis pathway genes found in other bacteria. Both the purified O-antigen and capsular polysaccharides increased the ability of the avirulent A. hydrophila strain PPD35/85 to survive in naïve tilapia serum. However, the purified surface polysaccharides had no inhibitory effect on the adhesion of A. hydrophila PPD134/91 to carp epithelial cells.Surface polysaccharides, such as O-antigen and capsule, are important bacterial cell surface components. The O-antigen polysaccharide is covalently ligated to the lipid A-core complex and extends outward from the cell surface. The capsule is an extracellular polysaccharide enclosing the bacterium while remaining attached to the cell. Both the O-antigen polysaccharide and the capsule are composed of repeating oligosaccharide units (44). They act as prominent antigens and play important roles in the pathogenicity of many bacterial pathogens, such as protecting bacterial cells from complement-mediated serum killing (20, 30), acting as adhesion factors (31), protecting the bacteria from the effects of desiccation (38), and aiding survival in phagocytes (56). The serogrouping of bacterial strains within a genus is determined by the structural variability of surface polysaccharides. For example, Escherichia coli strains are divided into more than 160 serogroups based on the different surface polysaccharides (67). Klebsiella species have been classified into 72 serogroups based on the structural variability of their capsular polysaccharides (39).Aeromonas hydrophila is an important pathogen of a wide variety of aquatic and terrestrial animals, especially fish (4). In fish, it causes hemorrhagic septicemia, which often results in high mortalities in commercial aquaculture. Some strains of A. hydrophila are also reported to cause infections in humans. The clinical symptoms include septicemia (17), meningitis (25), peritonitis (35), pneumonia (32), myonecrosis (34), and diarrh...

show abstract

“…In fact, formation o biofilm allows this pathogen to resist chlorination of treated waters as well as numerous antimicrobial agents (Palú et al, 2006). The majority of Aeromonas infections manifest themselves as self-limiting gastroenteritis; however, in some instances (particularly in the young, elderly and other immunocompromised individuals), disease can range from superficial skin sequelae to more systemic infections including: cellulitis, bacteraemia, peritonitis and haemolytic-uraemic syndrome (Brouqui & Raoult, 2001;Chopra et al, 1993;Chopra et al, 1996;Chopra & Houston, 1999;Galindo et al, 2006;Janda et al, 1994;Kühn et al, 1997;Merino et al, 1995). However, not all infections occur in immunocompromised individuals.…”

Section: Introductionmentioning

confidence: 99%

Evaluation of the roles played by Hcp and VgrG type 6 secretion system effectors in Aeromonas hydrophila SSU pathogenesis

et al. 2013

View full text Add to dashboard Cite

Aeromonas hydrophila, a Gram-negative bacterium, is an emerging human pathogen equipped with both a type 3 and a type 6 secretion system (T6SS). In this study, we evaluated the roles played by paralogous T6SS effector proteins, hemolysin co-regulated proteins (Hcp-1 and -2) and valine glycine repeat G (VgrG-1, -2 and -3) protein family members in A. hydrophila SSU pathogenesis by generating various combinations of deletion mutants of the their genes. In addition to their predicted roles as structural components and effector proteins of the T6SS, our data clearly demonstrated that paralogues of Hcp and VgrG also influenced bacterial motility, protease production and biofilm formation. Surprisingly, there was limited to no observed functional redundancy among and/or between the aforementioned T6SS effector paralogues in multiple assays. Our data indicated that Hcp and VgrG paralogues located within the T6SS cluster were more involved in forming T6SS structures, while the primary roles of Hcp-1 and VgrG-1, located outside of the T6SS cluster, were as T6SS effectors. In terms of influence on bacterial physiology, Hcp-1, but not Hcp-2, influenced bacterial motility and protease production, and in its absence, increases in both of the aforementioned activities were observed. Likewise, VgrG-1 played a major role in regulating bacterial protease production, while VgrG-2 and VgrG-3 were critical in regulating bacterial motility and biofilm formation. In an intraperitoneal murine model of infection, all Hcp and VgrG paralogues were required for optimal bacterial virulence and dissemination to mouse peripheral organs. Importantly, the observed phenotypic alterations of the T6SS mutants could be fully complemented. Taking these results together, we have further established the roles played by the two known T6SS effectors of A. hydrophila by defining their contributions to T6SS function and virulence in both in vitro and in vivo models of infection.

show abstract

Aeromonas Species in Septicemia: Laboratory Characteristics and Clinical Observations

Cited by 152 publications

References 20 publications

Different Clinical Characteristics between Polymicrobial and Monomicrobial Aeromonas Bacteremia -A Study of 216 Cases

Different Clinical Characteristics between Polymicrobial and Monomicrobial Aeromonas Bacteremia -A Study of 216 Cases

NovelAeromonas hydrophilaPPD134/91 Genes Involved in O-Antigen and Capsule Biosynthesis

Evaluation of the roles played by Hcp and VgrG type 6 secretion system effectors in Aeromonas hydrophila SSU pathogenesis

Contact Info

Product

Resources

About