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Texas Heart Institute Journal Feb 2020Abiotrophia defectiva, a nutritionally deficient streptococcus, is a rare cause of infective endocarditis. It has been associated with hemophagocytic syndrome. We...
Abiotrophia defectiva, a nutritionally deficient streptococcus, is a rare cause of infective endocarditis. It has been associated with hemophagocytic syndrome. We present the first case of A. defectiva infective endocarditis that led to antineutrophil cytoplasmic antibody-associated glomerulonephritis. The patient was a 55-year-old man whose endocarditis affected the mitral and aortic valves. His course was complicated by atrial fibrillation, stroke, and glomerulonephritis. He was successfully treated with antibiotics and dual valve replacement.
Topics: Abiotrophia; Anti-Bacterial Agents; Antibodies, Antineutrophil Cytoplasmic; Aortic Valve; Endocarditis, Bacterial; Glomerulonephritis; Gram-Positive Bacterial Infections; Heart Valve Prosthesis Implantation; Humans; Male; Middle Aged; Mitral Valve; Treatment Outcome
PubMed: 32148451
DOI: 10.14503/THIJ-17-6575 -
BMC Musculoskeletal Disorders Apr 2016Granulicatella and Abiotrophia spp. are difficult to detect due to their complex nutritional requirements. Infections with these organisms are associated with high...
BACKGROUND
Granulicatella and Abiotrophia spp. are difficult to detect due to their complex nutritional requirements. Infections with these organisms are associated with high treatment failure rates. We report the first implant-associated infection caused by Granulicatella para-adiacens, which was cured with anti-microbial treatment consisting of anti-biofilm-active rifampin and debridement, exchange of mobile parts and retention of the prosthesis.
CASE PRESENTATION
Patient with a history of left hip arthroplasty presented with acute onset of fever, pain and limited range of motion of the left hip. Arthrocentesis of the affected joint yielded purulent fluid and exchange of mobile parts of the prosthesis, but retention of fixed components was performed. Granulicatella para-adiacens grew from preoperative and intraoperative cultures, including sonication fluid of the removed implant. The transesophageal echocardiography showed a vegetation on the mitral valve; the orthopantogram demonstrated a periapical dental abscess. The patient was treated with intravenous penicillin G and gentamicin for 4 weeks, followed by levofloxacin and rifampin for additional 2 months. At discharge and at follow-up 1, 2 and 5 years later, the patient was noted to have a functional, pain-free, and radiologically stable hip prosthesis and the serum C-reactive protein was normal.
CONCLUSIONS
Although considered a difficult-to-treat organism, we report a successful treatment of the Granulicatella hip prosthesis infection with prosthesis retention and a prolonged antibiofilm therapy including rifampin. The periapical dental abscess is considered the primary focus of hematogenously infected hip prosthesis, underlining the importance treatment of periodontitis prior to arthroplasty and of proper oral hygiene for prevention of hematogenous infection after arthroplasty.
Topics: Abiotrophia; Aged; Anti-Bacterial Agents; Arthroplasty, Replacement, Hip; Debridement; Gram-Positive Bacterial Infections; Humans; Male; Prosthesis Retention; Prosthesis-Related Infections; Treatment Outcome
PubMed: 27067804
DOI: 10.1186/s12891-016-1008-9 -
Journal of Biological Inorganic... Sep 2019Outside of the photosynthetic machinery, high-valent manganese cofactors are rare in biology. It was proposed that a recently discovered subclass of ribonucleotide...
Outside of the photosynthetic machinery, high-valent manganese cofactors are rare in biology. It was proposed that a recently discovered subclass of ribonucleotide reductase (RNR), class Id, is dependent on a Mn(IV,III) cofactor for catalysis. Class I RNRs consist of a substrate-binding component (NrdA) and a metal-containing radical-generating component (NrdB). Herein we utilize a combination of EPR spectroscopy and enzyme assays to underscore the enzymatic relevance of the Mn(IV,III) cofactor in class Id NrdB from Facklamia ignava. Once formed, the Mn(IV,III) cofactor confers enzyme activity that correlates well with cofactor quantity. Moreover, we present the X-ray structure of the apo- and aerobically Mn-loaded forms of the homologous class Id NrdB from Leeuwenhoekiella blandensis, revealing a dimanganese centre typical of the subclass, with a tyrosine residue maintained at distance from the metal centre and a lysine residue projected towards the metals. Structural comparison of the apo- and metal-loaded forms of the protein reveals a refolding of the loop containing the conserved lysine and an unusual shift in the orientation of helices within a monomer, leading to the opening of a channel towards the metal site. Such major conformational changes have not been observed in NrdB proteins before. Finally, in vitro reconstitution experiments reveal that the high-valent manganese cofactor is not formed spontaneously from oxygen, but can be generated from at least two different reduced oxygen species, i.e. HO and superoxide (O ). Considering the observed differences in the efficiency of these two activating reagents, we propose that the physiologically relevant mechanism involves superoxide.
Topics: Aerococcaceae; Crystallography, X-Ray; Electron Spin Resonance Spectroscopy; Flavobacteriaceae; Free Radicals; Hydrogen Peroxide; Manganese; Oxidation-Reduction; Ribonucleotide Reductases; Superoxides
PubMed: 31414238
DOI: 10.1007/s00775-019-01697-8 -
The New Microbiologica Oct 2014We analyzed the in vitro susceptibility to several ?-lactams and vancomycin of 80 Aerococcus urinae isolates collected during 2011-2012 in Switzerland. MICs were...
We analyzed the in vitro susceptibility to several ?-lactams and vancomycin of 80 Aerococcus urinae isolates collected during 2011-2012 in Switzerland. MICs were determined by Etest (bioMérieux) on Müller-Hinton agar with 5% sheep blood and interpreted according to the CLSI and EUCAST criteria set for viridans streptococci. MIC50/90 for penicillin, amoxicillin, ceftriaxone and vancomycin were 0.016/0.064 mg/l, 0.032/0.064 mg/l, 0.125/0.5 mg/l and 0.38/0.5 mg/l, respectively. Three (3.8%) isolates were resistant to ceftriaxone regardless of the criteria used (MICs ?2 mg/l); one of them was also non-susceptible to penicillin (MIC of 0.25 mg/l) according to CLSI. β-lactam resistance in A. urinae is a concern and suggests that more studies are needed to determine the molecular mechanisms of such resistance.
Topics: Aerococcus; Aged; Aged, 80 and over; Anti-Bacterial Agents; Drug Resistance, Bacterial; Female; Gram-Positive Bacterial Infections; Humans; Male; Microbial Sensitivity Tests; Switzerland; beta-Lactams
PubMed: 25387295
DOI: No ID Found -
Journal of Oral Science Jan 2020Granulicatella adiacens (G. adiacens) and Abiotrophia defectiva (A. defectiva) colonize the oral cavity and form part of the normal flora in the intestinal and...
Contribution of different adherent properties of Granulicatella adiacens and Abiotrophia defectiva to their associations with oral colonization and the risk of infective endocarditis.
Granulicatella adiacens (G. adiacens) and Abiotrophia defectiva (A. defectiva) colonize the oral cavity and form part of the normal flora in the intestinal and genitourinary tracts. As reported previously, the frequency of isolation of G. adiacens from the oral cavity was much higher than that of A. defectiva. However, it has been reported that compared with G. adiacens, A. defectiva was isolated at considerably higher frequencies from the blood of patients with infective endocarditis (IE). Hence, in this study, the in vitro interaction of G. adiacens and A. defectiva strains with host surfaces and biofilm formation was examined to assess whether their different adhesive properties contribute to their associations with oral colonization and IE, respectively. G. adiacens exhibited an increased binding ability to saliva-coated hydroxyapatite beads than A. defectiva following the addition of CaCl. Furthermore, biofilm formation was observed only for G. adiacens with the use of a polystyrene tube and scanning electron microscopy analysis. Conversely, A. defectiva displayed significantly greater adherence to human umbilical vein endothelial cells and immobilized fibronectin than G. adiacens. These findings suggest that differences in binding properties to host components imply specific binding mechanisms in G. adiacens and A. defectiva, which might mediate selective colonization in the oral cavity or are associated with the pathogenicity of endocarditis.
Topics: Abiotrophia; Endocarditis, Bacterial; Endothelial Cells; Humans; Streptococcus
PubMed: 31708553
DOI: 10.2334/josnusd.19-0021 -
Mikrobiyoloji Bulteni Jul 2019Globicatella sanguinis is catalase-negative, alpha-hemolytic, nonmotile, facultative anaerobic grampositive cocci, identified as a new species in 1992. Since the colony...
Globicatella sanguinis is catalase-negative, alpha-hemolytic, nonmotile, facultative anaerobic grampositive cocci, identified as a new species in 1992. Since the colony morphology in blood agar and microscopic appearance resembles streptococci, it is thought that some of the isolates previously identified in the Streptococcus viridans group were G.sanguinis species. G.sanguinis has been isolated from various clinical specimens, its species identification and antibiotic susceptibility have been tested since the year it was identified. Clinical specimens in which it is isolated include various mucosal surfaces, blood, urine, wound and cerebrospinal fluid. In this report, considering also the literature information, a case of G.sanguinis which is thought to cause meningitis was presented. Our case is a 39-year-old female patient with a lumboperitoneal shunt. The patient was admitted to the neurosurgery clinic with a headache and vision loss and was hospitalized in the service with a pre-diagnosis of pseudotumor cerebri. Neurological examination revealed no pathological findings. Eye examination revealed mild papillary edema, local retinal hemorrhage, and bilateral expansion in retinal vascularization. There was no pathologic findings in the brain magnetic resonance imaging. The colonies resembling alpha hemolytic streptococci were isolated from the cerebrospinal fluid taken upon the development of neck stiffness, fever, and tachycardia on the 10th day of hospitalization of the lumbo-peritoneal shunt administered patient. The identification of the isolate was determined in Bruker IVD MALDI Biotyper 2.3 (Bruker Daltonik GmbH, Bremen, Germany), available in our laboratory and it was identified as G.sanguinis (KJ680157.1) with a score of > 2. The definite identification of the isolate at the species level was made by 16S rDNA sequence analysis and it was determined that the bacterium was G.sanguinis with 100% similarity and coverage. The minimum inhibitory concentration (MIC) for some of the antibiotics was determined by the agar gradient method. The MIC values were found as; linezolid 0.50 µg/ml, vancomycin 0.75 µg/ ml, imipenem 0.75 µg/ml, meropenem 3 µg/ml, penicillin G 6 µg/ml and cefotaxime > 32 µg/ml. It is known that these rare isolates can be isolated in greater numbers along with the introduction of MALDITOF MS-based devices in many laboratories. Following greater numbers of isolation of this rare species of bacteria, our knowledge about its clinical significance, placement in the flora and antibiotic susceptibility will also be expanded.
Topics: Adult; Aerococcaceae; Anti-Bacterial Agents; Female; Germany; Humans; Meningitis; Microbial Sensitivity Tests; Peritoneovenous Shunt; RNA, Ribosomal, 16S
PubMed: 31414636
DOI: 10.5578/mb.68131 -
Sensors (Basel, Switzerland) May 2020In this paper, a novel electron mediator, 1-methoxy-5-ethyl phenazinium ethyl sulfate (mPES), was introduced as a versatile mediator for disposable enzyme sensor strips,...
In this paper, a novel electron mediator, 1-methoxy-5-ethyl phenazinium ethyl sulfate (mPES), was introduced as a versatile mediator for disposable enzyme sensor strips, employing representative flavin oxidoreductases, lactate oxidase (LOx), glucose dehydrogenase (GDH), and fructosyl peptide oxidase (FPOx). A disposable lactate enzyme sensor with oxygen insensitive -derived engineered LOx (LOx), with A96L mutant as the enzyme, was constructed. The constructed lactate sensor exhibited a high sensitivity (0.73 ± 0.12 μA/mM) and wide linear range (0-50 mM lactate), showings that mPES functions as an effective mediator for LOx. Employing mPES as mediator allowed this amperometric lactate sensor to be operated at a relatively low potential of +0.2 V to 0 V vs. Ag/AgCl, thus avoiding interference from uric acid and acetaminophen. The lactate sensors were adequately stable for at least 48 days of storage at 25 °C. These results indicated that mPES can be replaced with 1-methoxy-5-methyl phenazinium methyl sulfate (mPMS), which we previously reported as the best mediator for LOx-based lactate sensors. Furthermore, this study revealed that mPES can be used as an effective electron mediator for the enzyme sensors employing representative flavin oxidoreductases, GDH-based glucose sensors, and FPOx-based hemoglobin A1c (HbA1c) sensors.
Topics: Aerococcus; Amino Acid Oxidoreductases; Biosensing Techniques; Electrons; Glucose Dehydrogenases; Mixed Function Oxygenases; Sulfuric Acid Esters
PubMed: 32429321
DOI: 10.3390/s20102825 -
International Journal of Food... Apr 2017The aim of this study was to investigate the influence of the slaughter technique (Halal vs Classical slaughter) on the superficial contamination of cattle carcasses, by...
The aim of this study was to investigate the influence of the slaughter technique (Halal vs Classical slaughter) on the superficial contamination of cattle carcasses, by using traditional microbiological procedures and 16S rDNA metagenetics. The purpose was also to investigate the neck area to identify bacteria originating from the digestive or the respiratory tract. Twenty bovine carcasses (10 from each group) were swabbed at the slaughterhouse, where both slaughtering methods are practiced. Two swabbing areas were chosen: one "legal" zone of 1600cm (composed of zones from rump, flank, brisket and forelimb) and locally on the neck area (200cm). Samples were submitted to classical microbiology for aerobic Total Viable Counts (TVC) at 30°C and Enterobacteriaceae counts, while metagenetic analysis was performed on the same samples. The classical microbiological results revealed no significant differences between both slaughtering practices; with values between 3.95 and 4.87log CFU/100cm and 0.49 and 1.94log CFU/100cm, for TVC and Enterobacteriaceae respectively. Analysis of pyrosequencing data showed that differences in the bacterial population abundance between slaughtering methods were mainly observed in the "legal" swabbing zone compared to the neck area. Bacterial genera belonging to the Actinobacteria phylum were more abundant in the "legal" swabbing zone in "Halal" samples, while Brevibacterium and Corynebacterium were encountered more in "Halal" samples, in all swabbing areas. This was also the case for Firmicutes bacterial populations (families of Aerococcaceae, Planococcaceae). Except for Planococcoceae, the analysis of Operational Taxonomic Unit (OTU) abundances of bacteria from the digestive or respiratory tract revealed no differences between groups. In conclusion, the slaughtering method does not influence the superficial microbiological pattern in terms of specific microbiological markers of the digestive or respiratory tract. However, precise analysis of taxonomy at the genus level taxonomy highlights differences between swabbing areas. Although not clearly proven in this study, differences in hygiene practices used during both slaughtering protocols could explain the differences in contamination between carcasses from both slaughtering groups.
Topics: Abattoirs; Animals; Bacteria; Cattle; Colony Count, Microbial; Food Contamination; Food Microbiology; Hygiene; Meat
PubMed: 27756497
DOI: 10.1016/j.ijfoodmicro.2016.10.013 -
Journal of Clinical Microbiology Aug 2016The Etest on chocolate Mueller-Hinton agar was compared to broth microdilution (BMD) for 125 isolates of nutritionally variant streptococci. Vancomycin Etests yielded... (Comparative Study)
Comparative Study
The Etest on chocolate Mueller-Hinton agar was compared to broth microdilution (BMD) for 125 isolates of nutritionally variant streptococci. Vancomycin Etests yielded 31.1% essential agreement (EA) and 20.0% categorical agreement (CA). Penicillin Etests yielded 86.0% EA and 85.6% CA, whereas ceftriaxone Etests yielded 73.6% EA and 68.0% CA.
Topics: Abiotrophia; Anti-Bacterial Agents; Carnobacteriaceae; Culture Media; Disk Diffusion Antimicrobial Tests; Humans
PubMed: 27280419
DOI: 10.1128/JCM.00822-16 -
BMC Urology Dec 2020Transurethral resection of the prostate (TUR-P) is one of the most frequent routine procedures in urology. Because of the semisterile environment, postoperative...
BACKGROUND
Transurethral resection of the prostate (TUR-P) is one of the most frequent routine procedures in urology. Because of the semisterile environment, postoperative infections, including sepsis, are a common complication, with Escherichia coli, Klebsiella spp., Proteus mirabilis or Enterococcus faecalis as frequently isolated pathogens. Facklamia hominis is a gram-positive, facultatively anaerobic, alpha-hemolytic, catalase-negative coccus that was first described in 1997. To date, only a few cases of infectious complications have been described. We report the first case of postoperative bacteremia due to Facklamia hominis after TUR-P.
CASE PRESENTATION
An 82-year-old man developed fever only a few hours after elective TUR-P because of benign prostate syndrome. After cultivation of blood cultures, antibiotic therapy with ceftriaxone was intravenously administered and changed to oral cotrimoxazole before discharge of the afebrile patient. One anaerobic blood culture revealed Facklamia hominis. Under antibiotic therapy, the patient remained afebrile and showed no signs of infections during follow-up.
CONCLUSIONS
Fever and bacteremia are frequent complications after TUR-P. This study is the first report of Facklamia hominis in a postoperative blood culture after TUR-P. To date, there are only a few reports of patients with infectious complications and isolation of Facklamia hominis in various patient samples. Because Facklamia hominis resembles viridans streptococci on blood agar analysis, this pathogen may often be misidentified. In this case identification of Facklamia hominis was possible with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. It has been postulated that Facklamia hominis might be a facultative pathogen and that its incidence will increase in the future.
Topics: Aerococcaceae; Aged, 80 and over; Bacteremia; Gram-Positive Bacterial Infections; Humans; Male; Postoperative Complications; Transurethral Resection of Prostate
PubMed: 33287796
DOI: 10.1186/s12894-020-00762-8