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Structural study and serological characterisation of the O-specific polysaccharide of Hafnia alvei PCM 1185, another Hafnia O-antigen that contains 3,6-dideoxy-3-[(R)-3-hydroxybutyramido]-D-glucose.

The O-specific polysaccharide of H. alvei strain PCM 1185 contains D-glucose, D-glucuronic acid, 2-acetamido-2-deoxy-D-glucose, and 3,6-dideoxy-3-[(R)-3-hydroxybutyramido]-D-glucose (Qui3NAcyl) in the ratios 2:1:1:1 as well as O-acetyl groups. On the basis of sugar and methylation analyses of the polysaccharide before and after chemical modifications (O-deacetylation, carboxyl reduction, Smith degradation), as well as 1H and 13C NMR spectroscopy, including 1D sequential, selective spin-decoupling, 2D homonuclear and 13C,1H heteronuclear correlation spectroscopy (COSY), and 2D rotating-frame NOE spectroscopy, it was found that the polysaccharide has a pentasaccharide repeating unit with the following structure: [formula: see text] with O-acetyl groups present in nonstoichiometric amounts, mainly at position 2 of GlcA and position 6 of GlcNAc or lateral Glc. Serological study showed that H. alvei strain PCM 1185 can be placed in a new serotype D and that an O-acetyl group can be a part of its epitope.

Carbohydrate Conformation↗

[Transmission of plasmid Rldrd19 from E. coli to Hafnia].

Investigations carried out demonstrated a possibility of transmission of plasmid Rldrd19 from E. coli to Hafnia. The incidence of the plasmid transmission varied from 10(-7) to 10(-9) and depended on the properfies of Hafnia strains. Tra-operon of plasmid Rldrd19 in the Hafnia 614 strain functioned with the same efficacy as in E. coli. Plasmid Rldrd19 in Hafnia was unstable and was eliminated from the cells in case of storage at low temperatures. As shown, plasmid Rldrd19 was under strict replication control in Hafnia as in E. coli. Formation of the CCC-form of the plasmid Rldrd19 was suppressed in Hafnia at 29--30 degrees C and was not suppressed in E. coli.

Chloramphenicol↗

Abdominal abscess and Hafnia alvei septicemia occurring during the aplastic phase after autologous stem-cell transplantation in a patient with diffuse large B-cell lymphoma.

Hafnia alvei is a motile gram-negative bacterium that is rarely isolated from human specimens, but that sometimes can be found as part of the gastrointestinal flora. Here we report a rare case of Hafnia alvei septicemia with an abdominal abscess in a 60-year-old woman with diffuse large B-cell lymphoma involving the spleen, liver, and then lymph nodes. She initially received a splenectomy, and, over a 2-year period, four courses of chemotherapy. After achieving complete remission status, she underwent autologous peripheral blood stem-cell transplantation (PBSCT). During the aplastic phase following transplantation, the patient developed fever, diarrhea, and abdominal pain, with blood cultures positive for Hafnia alvei and an abscess in the splenic recess. Considering the high surgical risk, the infection was treated, successfully, with antibiotics (imipenem/cilastatin), without surgery or computed tomography (CT)-guided percutaneous drainage. Infections due to Hafnia alvei are rare, and this is the first reported case of Hafnia alvei septicemia in an adult hematologic patient undergoing a stem-cell transplantation procedure.

Abdominal Abscess↗

[Frequency of detecting bacteria of the genera Citrobacter and Hafnia in different contingents of examined adults].

A study of the incidence of bacteria of the Citrobacter and Hafnia genus in adults permitted to establish a greater occurrence of the mentioned microbes in the patients with various acute intestinal diseases in comparison with the healthy ones. Bacteria of the Citrobacter and Hafnia genus were revealed in the patients with acute intestinal diseases of obscure etiology, which often were diagnosed as gastroenteritis, enteritis, etc. Bacteria of the Citrobacter and Hafnia genus were revealed in the dysentery patients. Results of studies carried out among various healthy groups of the population indicated no significant differences in respect to the carrier state of the Citrobacter and Hafnia bacteria both within each of the groups of the persons examined and between them. Further studies directed to the investigation of the etiological role of bacteria of the Citrobacter and Hafnia genus in the pathology of enteric disturbances are necessary.

Acute Disease↗

[Resistance to antibiotics of conditionally pathogenic enterobacteria of the genera, Citrobacter and Hafnia].

Antibiotic sensitivity of 363 strains of Citrobacter and 124 strains of Hafnia isolated from patients with acute intestine infections and healthy persons was studied. It was found that 44.6 per cent of the Citrobacter isolates and 36.3 per cent of the Hafnia isolates were resistant to one or more antibiotics. Different sensitivity of the bacteria of these 2 genera of the conditionally pathogenic enterobacteria to definite antibiotics was shown. The resistant strains of Citrobacter to negramon, monomycin, levomycetin, polymyxin, streptomycin and tetracycline amounted to 3, 6.1, 24, 14.3, 24.8 and 25.9 per cent, respectively. Among the Hafnia isolates the resistant strains to negramone, levomycetin, polymyxin and tetracyline amounted to 0.8, 8.9, 29.8 and 25 per cent, respectively. All the tested strains of Hafnia were sensitive to monomycin and streptomycin. Comparison of the culture antibiotic sensitivity with respect to the resistance spectra revealed 24 and 5 types of resistance in the cultures of Citrobacter and Hafnia, respectively.

Anti-Bacterial Agents↗

Extraintestinal infection due to Hafnia alvei.

The aim of this study was to establish the clinical features of extraintestinal infections caused by Hafnia alvei. Over a 5-year period (1994-1998), data were collected regarding inpatients (n = 8) with nosocomial (n = 5) or community-acquired (n = 3) infections caused by Hafnia alvei. The mean age of the patients was 47 +/- 21 years. Three patients had hospital-acquired urinary tract infections. Hafnia alvei also caused community-acquired cholangitis, cholecystitis, appendicitis, psoas abscess and prosthetic endocarditis. Hafnia alvei was susceptible to amoxicillin/clavulanic acid and to first-generation cephalosporins in two cases. Susceptibility to aminoglycosides, imipenem, cotrimoxazole, ciprofloxacin, piperacillin and cefotaxime was very good (8/8). Four patients required invasive treatment.

Adult↗

Phenotypic and genotypic properties of the genus Hafnia.

The present study characterised 73 Hafnia alvei isolates and five Escherichia isolates (originally identified as H. alvei) isolated from cases of diarrhoeal disease by the International Centre for Diarrhoeal Disease Research Branch (ICDDRB) in Bangladesh. Based upon the hydrolysis of arbutin and aesculin and the fermentation of salicin and D-arabinose, four distinct biotypes could be recognised among the 73 H. alvei isolates tested; biotype 1 (D-(-)-arabinose-positive only) accounted for 75% of all isolates analysed. Hydrolysis of aglycone compounds such as arbutin, salicin and aesculin appeared to be associated with expression of beta-glucosidase activity. ICDDRB isolates, when compared with type or reference strains of H. alvei, were shown not to belong to the genus Hafnia based upon resistance to Hafnia-specific bacteriophage 1672, possession of the phoE gene, expression of glutamate decarboxylase activity and significant 16S rDNA sequence divergence (approximately 8%) from the type strain, ATCC 13337T. True H. alvei strains, implicated in outbreaks of diarrhoeal disease in Canada, lacked the eaeA gene in contrast to ICDDRB isolates. Twenty-two H. alvei isolates were selected for further study. Based upon partial 16S rDNA sequencing, these 22 isolates fell into two genomic groups (genomospecies), identical to DNA groups previously established by DNA hybridisation studies. Markers such as motility, biotype, or enzymic or carbohydrate fermentation patterns did not correlate totally with DNA grouping, although malonate utilisation appeared to be the single best discriminatory phenotype. The results indicate that the genus Hafnia is heterogeneous and there do not appear to be any laboratory data available specifically linking these organisms to gastro-enteritis.

Adhesins, Bacterial↗

Population-based laboratory surveillance of Hafnia alvei isolates in a large Canadian health region.

BACKGROUND: Hospital-based series have characterized Hafnia alvei primarily as an infrequent agent of polymicrobial nosocomial infections in males with underlying illness. METHODS: We conducted population-based laboratory surveillance in the Calgary Health Region during 2000-2005 to define the incidence, demographic risk factors for acquisition, and anti-microbial susceptibilities of Hafnia alvei isolates. RESULTS: A total of 138 patients with Hafnia alvei isolates were identified (2.1/100,000/year) and two-thirds were of community onset. Older age and female gender were important risk factors for acquisition. The most common focus of isolation was urine in 112 (81%), followed by lower respiratory tract in 10 (7%), and soft tissue in 5 (4%), and the majority (94; 68%) were mono-microbial. Most isolates were resistant to ampicillin (111;80%), cephalothin (106; 77%), amoxicillin/clavulanate (98; 71%), and cefazolin (95; 69%) but none to imipenem or ciprofloxacin. CONCLUSION: Hafnia alvei was most commonly isolated as a mono-microbial etiology from the urinary tract in women from the community. This study highlights the importance of population-based studies in accurately defining the epidemiology of an infectious disease.

Age Distribution↗

Biosynthesis of bacterial glycogen: characterization of adenosine diphosphate glucose synthetases from Enterobacter hafniae and Aeromonas hydrophila.

Enterobacter hafniae and Aeromonas hydrophila ADPglucose synthetases were purified approximately 39- and 61-fold, respectively, over the crude extract. Both enzymes were heat stable at 60 degrees C in the presence of inorganic phosphate. The molecular weights of both enzymes were approximately 200,000 which are similar to other enteric ADPglucose synthetases studied. Based on kinetic results obtained from the partially purified enzymes, the E. hafniae enzyme is activated twofold by phospho-enolpyruvate while the A. hydrophila enzyme is activated twofold by fructose 6-P and 1.5-fold by fructose 1,6 bis-phosphate. The E. hafniae enzyme activity is strongly inhibited by AMP and ADP and the inhibition can be partially reversed by P-enolpyruvate. ADP is the most effective inhibitor of the A. hydrophila enzyme and its inhibition can be partially overcome by the presence of the activators fructose 6-P and fructose 1,6-P2. These kinetic results show that the allosteric properties of the E. hafniae enzyme are distinctly different from the ADPglucose synthetases of those previously studied from bacteria of the genus Enterobacter. Although the A. hydrophila enzyme is activated by fructose 1,6-P2, its allosteric properties are quite different than those observed for ADPglucose synthetase of the Enterobacteriaceae.

Adenosine Diphosphate↗

Calculation of the fresh gas flow requirements of the Hafnia A and D anaesthetic circuits.

Semi-closed anaesthetic circuits are converted into the corresponding Hafnia circuits by replacing the expiratory valve by a side tube connected to an ejector flowmeter. Theoretical analysis of the Hafnia A and D circuits revealed by the fresh gas flow requirements are dependent on the inspiration/expiration time ratio. Using a ratio of 1/1.2 and a sine-wave respiratory waveform, the minimal fresh gas requirements were calculated as 2.1 (Hafnia A) and 2.5 (Hafnia D) times the respiratory minute volume. The fresh gas requirements are identical with spontaneous or controlled ventilation.

Anesthesia, Inhalation↗

[Studies of humoral immunity induced by proteins of the cell wall of Hafnia alvei].

It was found that cell wall proteins (CWP) of Hafnia alvei applied intraperitoneally to mice are inducing, beside previously detected cellular immunity, also humoral immunity. Applying ELISA immunoenzymatic test in which a conjugate enabling demonstration of IgG antibodies was applied, it was found that CWP of Hafnia alvei induce appearance of specific antibodies in a high titer, but their presence in mouse serum is short and independent from applied doses of CWP. Humoral immunity induced by CWP can be transferred passively to nonimmunized animals by application of high level immune serum, which protected fully the animals against infection with homological strains of Hafnia alvei even in dilution 1:100. Investigated serum did not exhibit protective activity against infection with heterological strains of Hafnia alvei.

Animals↗

The genus Hafnia: from soup to nuts.

The genus Hafnia, a member of the family Enterobacteriaceae, consists of gram-negative bacteria that are occasionally implicated in both intestinal and extraintestinal infections in humans. Despite the fact that the genus currently contains only a single species (H. alvei), more extensive phylogenetic depth (two or more species) is apparent based upon DNA relatedness and 16S rRNA gene sequencing studies. Hafnia causes a variety of systemic infections, including septicemia and pneumonia; however, its role as a gastrointestinal pathogen is controversial. Many of the data supporting a role for hafniae as enteric pathogens were incorrectly attributed to this genus rather than to the actual pathogen, Escherichia albertii. There are numerous gaps in our understanding of this genus, including ecologic habitats and population genetics, disease-producing role in animals, phenetic and genetic methods useful in distinguishing genomospecies within the H. alvei complex, and bona fide pathogenicity factors.

Animals↗

Identification of two distinct hybridization groups in the genus Hafnia by 16S rRNA gene sequencing and phenotypic methods.

A collection of 52 strains belonging to the Hafnia alvei complex were subjected to molecular (16S rRNA gene sequencing) and biochemical analysis. Based upon 16S rRNA gene sequencing results, two genetic groups were identified which correspond with previously recognized DNA hybridization group 1 (ATCC 13337(T) and ATCC 29926; n = 23) and DNA hybridization group 2 (ATCC 29927; n = 29). Of 46 biochemical tests used to characterize hafniae, 19 reactions (41%) yielded variable results. Of these 19 tests, 6 were determined to have discriminatory value in the separation of DNA groups 1 and 2, with malonate utilization found to be the most differential test. Test results of malonate utilization alone correctly assigned 90% of Hafnia isolates to their correct DNA group.

Bacterial Typing Techniques↗

Natural antimicrobial susceptibility patterns and biochemical identification of Escherichia albertii and Hafnia alvei strains.

Bangladeshi diarrheagenic Hafnia alvei-like strains have been described recently as the new species Escherichia albertii (Int J Syst Evolut Microbiol. 2003;53:807-810). The natural susceptibility of 21 E. albertii and 76 H. alvei strains to 69 antimicrobial agents was examined, applying a microdilution procedure in IsoSensitest broth (for all the strains) and cation-adjusted Mueller-Hinton broth (for some strains). Examining the phenotypic features of both taxa with commercial identification systems and conventional tests, a database for an accurate biochemical separation of E. albertii from H. alvei was also established. Both taxa were naturally sensitive or sensitive and of intermediate susceptibility to aminoglycosides, acylureidopenicillins, ticarcillin, several cephalosporins, carbapenems, aztreonam, quinolones, folate pathway inhibitors, and nitrofurantoin. They were naturally resistant to tetracycline, penicillin G, oxacillin, all macrolides except for azithromycin, lincosamides, streptogramins, glycopeptides, rifampicin, and fusidic acid. Taxon-related differences in natural susceptibility affecting clinical assessment criteria were seen with doxycycline, minocycline, aminopenicillins, some cephalosporins, azithromycin, and fosfomycin. E. albertii was more susceptible than H. alvei to these agents and was naturally sensitive to all beta-lactams (except for penicillin G and oxacillin), azithromycin, and fosfomycin. H. alvei was naturally resistant or of intermediate susceptibility to all tetracyclines, amoxicillin, amoxicillin-clavulanate, ampicillin-sulbactam, narrow-spectrum cephalosporins, azithromycin, and fosfomycin. Motile malonate-negative Hafnia strains (indicating genospecies 2 of the H. alvei complex) were less susceptible to some cephalosporins than nonmotile, malonate-positive hafniae (indicating genospecies 1). Proline deaminase, hydroxyproline amidase, tripeptidase, chitinase, Voges-Proskauer reaction, and assimilation of histidine as well as acid production from glycerol, rhamnose, and xylose were suitable tests to separate strains of E. albertii from those of the H. alvei complex. Although out of the scope of this study, it should be noted that several strains of E. albertii showed acquired resistances to some penicillins and antifolates.

Anti-Bacterial Agents↗

Delayed-onset postoperative endophthalmitis caused by Hafnia alvei.

PURPOSE: To identify Hafnia alvei as an etiological factor of delayed-onset endophthalmitis. CASE REPORT: A 68-year-old woman had uneventful cataract extraction by phacoemulsification with foldable posterior chamber intraocular lens implantation under topical anesthesia in the left eye. Four weeks later, the patient presented anterior uveitis treated by topical corticosteroids. Seven weeks later a posterior uveitis with retinal vasculitis appeared. The patient was treated by systemic and intravitreal corticosteroids without result. Due to the poor course pars plana vitrectomy was done, and a vitreous sample was taken. Microbiologic examination disclosed Hafnia alvei, gram-negative bacteria rarely isolated from human specimens. CONCLUSIONS: Hafnia alvei should be considered in the etiology of delayed-onset endophthalmitis.

Aged↗

[Hafnia alvei septicemia with shock and DIC in an adult with postoperative lung cancer].

In Japan, we experienced the first case of Hafnia alvei septicemia with shock and disseminated intravascular coagulation (DIC) in an adult with postoperative lung cancer. A 63 year-old male, who had been followed up in our department since 1987, was admitted to our hospital with the complaints of fever, hemoptysis and dyspnea on June 25, 1989. After admission, he was treated with sulbactam/cefoperazone 4 g/day intravenously for suspicion of respiratory-tract infection. After antibiotic administration, the fever subsided and the general condition became almost good. The patient experienced fever again after the antibiotic was stopped. For this reason subsequent Clavulanic acid/Amoxicillin, Flomoxef, and Ceftazidime was administered, but was not effective. Therefore septicemia was suspected and blood culture was done. The bacteria isolated from blood culture was identified as Hafnia alvei. Hafnia alvei is a gram-negative organism belonging to the Enterobacteriaceae family and quite rare pathogen in human.

Bacteremia↗

Prototypal diarrheagenic strains of Hafnia alvei are actually members of the genus Escherichia.

We analyzed five bacterial strains, designated 19982, 9194, 10457, 10790, and 12502, that were isolated from stool specimens of individuals with diarrheal illness by the International Centre for Diarrhoeal Disease Research in Dhaka, Bangladesh (M. J. Albert, S. M. Faruque, M. Ansaruzzaman, M. M. Islam, K. Haider, K. Alam, I. Kabir, and R. Robins-Browne, J. Med. Microbiol. 37:310-314, 1992). The strains were initially identified as Hafnia alvei with a commercial identification system and were reported to contain the eae gene of enteropathogenic Escherichia coli. Results of conventional biochemical analyses, testing of susceptibility to cephalothin, lysis by a Hafnia-specific phage, and amplification of the outer membrane protein gene phoE with species-specific primers support the identification of these strains as members of the genus Escherichia rather than Hafnia alvei. These strains varied from typical E. coli strains by their inability to produce acid from lactose or D-sorbitol and failure to elaborate the enzyme beta-D-glucuronidase. PCR analysis confirmed previous findings that the strains were positive for the eae gene and negative for other virulence markers present among recognized categories of diarrheagenic E. coli. Our findings support the hypothesis that these strains are a new category of diarrheagenic isolates belonging to the genus Escherichia and illustrate the importance of using multiple methodologies when identifying new bacterial agents of diarrheal disease.

Diarrhea↗

Structural studies on Hafnia alvei 114-60 O-antigen.

The structure of Hafnia alvei 114-60 O-antigen has been established using sugar and methylation analyses as well as 1H-NMR spectroscopy. The results obtained proved that the repeating unit of Hafnia alvei 114-60 O-antigen is identical to that of Hafnia alvei ATCC 13337 standard strain and has the following structure: [formula: see text]

Antigens, Bacterial↗