cefoxitin and Bacteremia

The role of piperacillin/tazobactam for treatment of serious infections due to AmpC-producing organisms remains debatable, particularly in immunocompromised patients.. This was a retrospective cohort study in immunocompromised patients that investigated the effect of definitive treatment with either piperacillin/tazobactam versus cefepime or carbapenems for bacteraemia caused by cefoxitin-non-susceptible Enterobacterales. The primary endpoint was a composite of clinical and microbiological failure. A logistic regression model was constructed to assess the impact of definitive treatment choice on the primary endpoint.. A total of 81 immunocompromised patients with blood cultures positive for cefoxitin-non-susceptible Enterobacterales were included for analysis. There was more microbiological failure in the piperacillin/tazobactam arm compared with the cefepime/carbapenem arm (11.4% versus 0.0%, P = 0.019). Definitive treatment with cefepime or a carbapenem was associated with a decreased odds of clinical or microbiological failure (OR 0.303, 95% CI 0.093-0.991, P = 0.048) when controlling for baseline characteristics.. In immunocompromised patients with bacteraemia due to cefoxitin-non-susceptible Enterobacterales, definitive treatment with piperacillin/tazobactam was associated with an increased risk of microbiological failure and higher odds of clinical or microbiological failure compared with cefepime or carbapenems.

Topics: Anti-Bacterial Agents; Bacteremia; beta-Lactamases; Carbapenems; Cefepime; Cefoxitin; Citrobacter freundii; Enterobacter aerogenes; Enterobacter cloacae; Humans; Microbial Sensitivity Tests; Morganella morganii; Piperacillin, Tazobactam Drug Combination; Retrospective Studies; Serratia marcescens

Despite cefoxitin's in vitro resistance to hydrolysis by extended-spectrum beta-lactamases (ESBL), treatment of ESBL-producing Klebsiella pneumoniae (KP) infections with cefoxitin remains controversial. The aim of our study was to compare the clinical efficacy of cefoxitin as definitive antibiotic therapy for patients with ESBL-KP bacteremia in intensive care unit, versus carbapenem therapy.. This retrospective study included all patients with monomicrobial bacteremia hospitalized in intensive care unit between January 2013 and January 2023 at the University Hospital of Guadeloupe. The primary outcome was the 30-day clinical success defined as a composite endpoint: 30-day survival, absence of relapse and no change of antibiotic therapy. Cox regression including a propensity score (PS) and PS-based matched analysis were performed for endpoint analysis.. A total of 110 patients with bloodstream infections were enrolled. Sixty-three patients (57%) received definitive antibiotic therapy with cefoxitin, while forty-seven (43%) were treated with carbapenems. 30-day clinical success was not significantly different between patients treated with cefoxitin (57%) and carbapenems (53%, p = 0.823). PS-adjusted and PS-matched analysis confirmed these findings. Change of definitive antibiotic therapy was more frequent in the cefoxitin group (17% vs. 0%, p = 0.002). No significant differences were observed for the other secondary endpoints. The acquisition of carbapenem-resistant Pseudomonas aeruginosa was significantly higher in patients receiving carbapenem therapy (5% vs. 23%, p = 0.007).. Our results suggest that cefoxitin as definitive antibiotic therapy could be a therapeutic option for some ESBL-KP bacteremia, sparing carbapenems and reducing the selection of carbapenem-resistant Pseudomonas aeruginosa strains.

Topics: Anti-Bacterial Agents; Bacteremia; beta-Lactamases; Carbapenems; Cefoxitin; Escherichia coli; Humans; Klebsiella pneumoniae; Retrospective Studies

Topics: Adult; Aged; Anti-Bacterial Agents; Bacteremia; Bacterial Proteins; Cefoxitin; Female; Humans; Male; Methicillin-Resistant Staphylococcus aureus; Microbial Sensitivity Tests; Middle Aged; Oxacillin; Penicillin-Binding Proteins; Retrospective Studies; Staphylococcal Infections; Treatment Outcome; Vancomycin; Young Adult

In vitro trends of cefazolin and ceftriaxone susceptibilities from pediatric clinical isolates of methicillin-susceptible Staphylococcus aureus (MSSA) between 2011 and 2016 were analyzed for surveillance.. Our laboratory continues to use agar disk diffusion for staphylococcal susceptibilities applying Clinical Laboratory Standard Institute's 2012 breakpoints.. A total of 3992 MSSA clinical isolates in the last 6 years were analyzed for their in vitro cefazolin and ceftriaxone susceptibilities. While all MSSA isolates exhibited cefazolin susceptibilities within the "susceptible" zone range, there have been a proportion of isolates with ceftriaxone susceptibilities falling in "intermediate" zones, ranging from 2.6% in 2011 to 8.3% in 2016.. Cefazolin continues to be the recommended agent for MSSA treatment at our institution, reflected by the finding that only 2% (6/321) of patients who received ceftriaxone as definitive therapy for MSSA bacteremia during the study period. We have confirmed the cefoxitin-predicted MSSA susceptibility to cefazolin, but have found concerning drifts in ceftriaxone susceptibilities by continued in vitro monitoring over the last 6 years.

Topics: Anti-Bacterial Agents; Bacteremia; Cefazolin; Cefoxitin; Ceftriaxone; Disk Diffusion Antimicrobial Tests; Humans; Methicillin-Resistant Staphylococcus aureus; Staphylococcal Infections; Staphylococcus aureus

The aim of the study was to validate whether rapid antimicrobial susceptibility testing (AST) by very early reading of disc diffusion tests would provide reliable results in daily routine work. A total of 264 positive blood culture bottles were examined, of which 178 were examined as part of the daily routine workflow. Enterobacterales were evaluated for resistance to cefotaxime, ceftazidime, gentamicin and ampicillin. Staphylococcus aureus (S. aureus) was tested for resistance to cefoxitin as a marker of methicillin-resistant S. aureus (MRSA). The zones were read after 3 h, and if there was insufficient growth, 30 and 60 min later. The results were compared to standard overnight AST. For ampicillin, gentamicin and cefoxitin, there were no errors. For cefotaxime, there were three minor (1.5%), three major (1.5%) and no very major errors. For ceftazidime, there were 13 minor (6.5%) errors only. With the exception of one minor error, all errors were ESBL-A- or AmpC-producing isolates where rapid AST showed a higher degree of resistance than standard AST. This low-cost method may contribute to early effective antibacterial treatment by providing reliable results of AST within 3-4 h. Special breakpoints for early reading are a prerequisite.

Topics: Ampicillin; Anti-Bacterial Agents; Bacteremia; Blood Culture; Cefotaxime; Cefoxitin; Ceftazidime; Diagnostic Errors; Disk Diffusion Antimicrobial Tests; Drug Resistance, Bacterial; Early Diagnosis; Enterobacteriaceae; Enterobacteriaceae Infections; Gentamicins; Humans; Methicillin-Resistant Staphylococcus aureus; Staphylococcal Infections; Time Factors

Vancomycin heteroresistance in coagulase negative Staphylococci (CoNS) is a recent health concern especially in serious infections like bloodstream infections as it may lead to failure of therapy. Little information is available about the prevalence vancomycin heteroresistance in CoNS causing bloodstream infections in intensive care units (ICUs) patients of Mansoura University Hospitals (MUHs).. This prospective study enrolled 743 blood samples collected from ICUs patients presented with clinical manifestations of bloodstream infections over the period extending from January 2014 to March 2016. Samples were processed, coagulase negative Staphylococci were identified by routine microbiological methods and the absence of coagulase activity. Species were identified by API Staph 32. Oxacillin resistant CoNS were identified by cefoxitin disc diffusion method. Susceptibility testing of isolated CoNS to vancomycin was carried out using vancomycin agar dilution method. Mec A gene detection by PCR was done for oxacillin resistant isolates. Screening for vancomycin heteroresistance was done on brain heart infusion (BHI) agar containing 4 μg/mL vancomycin. Confirmation of vancomycin heteroresistance was carried out by population analysis profile (PAP).. A total of 58 isolates were identified as CoNS from patients of clinically suspected bloodstream infections. The identified species were 33 (56.9%) Staphylococcus epidermidis, 12 (20.7%) Staphylococcus capitis, 7 (12.1%) Staphylococcus haemolyticus, and 3 isolates (5.2%) Staphylococcus lugdunesis. Three isolates were unidentified by API Staph 32. Forty-four (75.9%) isolates were oxacillin resistant. Mec A gene was detected in all oxacillin resistant isolates. All isolates had susceptible vancomycin MICs by agar dilution. Nine isolates (15.5%) could grow on BHI agar containing 4 μg/mL vancomycin. These isolates showed heterogeneous profile of resistance to vancomycin by population analysis profile.. Vancomycin heteroresistant CoNS causing bloodstream infections is growing unrecognized health hazard in ICUs patients. These isolates have susceptible vancomycin MICs. Screening methods are recommended and should be considered to improve clinical outcome in these high risk patients.

Topics: Anti-Bacterial Agents; Bacteremia; Bacterial Proteins; Cefoxitin; Coagulase; Drug Resistance, Bacterial; Egypt; Female; Genes, Bacterial; Hospitals, University; Humans; Intensive Care Units; Male; Microbial Sensitivity Tests; Oxacillin; Penicillin-Binding Proteins; Prospective Studies; Staphylococcal Infections; Staphylococcus; Vancomycin; Vancomycin Resistance

Staphylococcus haemolyticus is a coagulase-negative staphylococcus that is frequently isolated from blood cultures. Here, we report a case of methicillin-susceptible S. haemolyticus that is resistant to teicoplanin (TEC) and heteroresistant to vancomycin (VAN). The isolate was susceptible to cefoxitin and resistant to TEC by Etest. Population analysis profile-area under the curve analysis confirmed the presence of a VAN heteroresistant subpopulation. Next-generation sequencing analysis of the genome revealed the presence of blaZ and msr(A), which encode cross-resistance to macrolide, lincosamide, and streptogramin B, and the quinolone resistance-conferring gene norA. In addition, several amino acid substitutions were observed in the TEC resistance operon tcaRAB, including I3N, I390N, and L450I in tcaA and L44V, G52V, and S87P in tcaR, as well as in the transpeptidase encoding gene walK (D336Y, R375L, and V404A) and L315 and P316 in graS. We hypothesized that this combination of mutations could confer TEC resistance and reduced VAN susceptibility.

Topics: Amino Acid Substitution; Anti-Bacterial Agents; Bacteremia; Biological Variation, Population; Cefoxitin; Disk Diffusion Antimicrobial Tests; Drug Resistance, Bacterial; Female; Genes, Bacterial; Humans; Methicillin; Middle Aged; Mutation, Missense; Operon; Sequence Analysis, DNA; Staphylococcal Infections; Staphylococcus haemolyticus; Teicoplanin; Whole Genome Sequencing

Klebsiella pneumoniae is an important pathogen, increasingly notorious for its ability to become resistant to antimicrobial agents. This study sought to characterize trends in antimicrobial susceptibility rates for K. pneumoniae causing bacteremias across the United States (U.S.) Veterans Healthcare Administration (VHA) from 2007 through 2013 utilizing a national clinical database. K. pneumoniae grew in 9,235 blood cultures from 8,414 patients. Nationally, ampicillin-sulbactam, ceftazidime, cefepime, ertapenem, fluoroquinolones, and amikacin demonstrated statistically significant susceptibility rate increases against K. pneumoniae in the 2010-2013 period versus the 2007-2009 period. No antimicrobial agent had a statistically significant nationwide susceptibility rate decrease. Of the 126 antibiotic-organism pairs tested among 9 U.S. regions, 18 demonstrated statistically significant susceptibility rate increases while 6 demonstrated statistically significant susceptibility rate decreases. The East North Central (eight agents), Mid-Atlantic (five agents), and South Atlantic (four agents) regions demonstrated statistically significant susceptibility rate increases for multiple antimicrobial agents. Of the 70 antibiotic-organism pairs tested among 5 different medical center complexity levels, 11 antibiotics demonstrated statistically significant susceptibility rate increases and 1 demonstrated a statistically significant rate decrease. Extended-spectrum β-lactamase production did not significantly change over the study period across an available nationwide representation of 31 facilities (10.6% in 2007-2009 vs. 9.21% in 2010-2013, p=0.17). The South Atlantic and Mid-Atlantic regions had the highest prevalence of extended-spectrum ß-lactamase production in the two periods, respectively. The recent trend of generally increasing susceptibility rates for K. pneumoniae bloodstream isolates in this nationwide U.S. VHA study contrasts from other U.S. health system reports demonstrating increasing trends of antimicrobial resistance.

Topics: Amikacin; Ampicillin; Anti-Bacterial Agents; Bacteremia; beta-Lactamases; beta-Lactams; Cefepime; Cefoxitin; Ceftazidime; Cephalosporins; Drug Resistance, Multiple, Bacterial; Ertapenem; Fluoroquinolones; Gene Expression Regulation, Bacterial; Humans; Imipenem; Klebsiella Infections; Klebsiella pneumoniae; Microbial Sensitivity Tests; Sulbactam; United States; United States Department of Veterans Affairs

We aimed to characterise the staphylococcal cassette chromosome mec (SCCmec) type, genetic relatedness, biofilm formation and composition, icaADBC genes detection, icaD expression, and antibiotic susceptibility of planktonic and biofilm cells of Staphylococcus hominis isolates from blood.. The study included 67 S. hominis blood isolates. Methicillin resistance was evaluated with the cefoxitin disk test. mecA gene and SCCmec were detected by multiplex PCR. Genetic relatedness was determined by pulsed-field gel electrophoresis. Biofilm formation and composition were evaluated by staining with crystal violet and by detachment assay, respectively; and the biofilm index (BI) was determined. Detection and expression of icaADBC genes were performed by multiplex PCR and real-time PCR, respectively. Antibiotic susceptibilities of planktonic cells (minimum inhibitory concentration, MIC) and biofilm cells (minimum biofilm eradication concentration, MBEC) were determined by the broth dilution method.. Eighty-five percent (57/67) of isolates were methicillin resistant and mecA positive. Of the mecA-positive isolates, 66.7% (38/57) carried a new putative SCCmec type. Four clones were detected, with two to five isolates each. Among all isolates, 91% (61/67) were categorised as strong biofilm producers. Biofilm biomass composition was heterogeneous (polysaccharides, proteins and DNA). All isolates presented the icaD gene, and 6.66% (1/15) isolates expressed icaD. This isolate presented the five genes of ica operon. Higher BI and MBEC values than the MIC values were observed for amikacin, vancomycin, linezolid, oxacillin, ciprofloxacin, and chloramphenicol.. S. hominis isolates were highly resistant to methicillin and other antimicrobials. Most of the detected SCCmec types were different than those described for S. aureus. Isolates indicated low clonality. The results indicate that S. hominis is a strong biofilm producer with an extracellular matrix with similar composition of proteins, DNA and N-acetylglucosamine; and presents high frequency and low expression of icaD gene. Biofilm production is associated with increased antibiotic resistance.

Topics: Amidohydrolases; Anti-Bacterial Agents; Bacteremia; Bacterial Proteins; Biofilms; Cefoxitin; Chromosomes, Bacterial; Ciprofloxacin; Drug Resistance, Bacterial; Gene Expression Regulation, Bacterial; Humans; Methicillin; Microbial Sensitivity Tests; Operon; Oxacillin; Penicillin-Binding Proteins; Phylogeny; Plankton; Staphylococcal Infections; Staphylococcus hominis; Vancomycin

Methicillin-resistant Staphylococcus aureus (MRSA) strains carrying the mecC gene have been reported from humans and animals from several European countries, but never from Spain. We describe the first isolates of mecC-positive MRSA of human origin collected in Spain and report a fatal case of bacteraemia.. Isolates were tested for phenotypic resistance using cefoxitin, tested for the mecA/mecC genes and toxin genes by PCR, and typed by staphylococcal cassette chromosome mec (SCCmec), PFGE, spa, multilocus sequence typing and agr.. During 2008-13 five MRSA isolates showing resistance to cefoxitin and carrying the mecC gene were recovered at one hospital in Spain. In a review of 5505 S. aureus strains received at the Spanish National Reference Centre for Staphylococci from the same period, we found two additional mecC-positive isolates. The isolates were recovered from blood (two), wounds (two), joint fluid (one), urine (one) and a nasal swab (one). All MRSA were mecA negative, presented SCCmecXI, belonged to agr group III and to clonal complex 130, and were negative for the production of the toxin genes tst1, eta, etb, etd and Panton-Valentine leucocidin. Six isolates belonged to spa type t843 (ST130 and ST1945, where ST stands for sequence type) and one to spa type t6220 (ST1945). One patient with mecC-positive MRSA sepsis died in the emergency department.. We confirm the presence of MRSA carrying the mecC gene in Spain, the ability of this livestock-associated MRSA to cause severe infections in humans and the need to perform culture-based susceptibility testing methods in order to detect these emerging strains.

Topics: Aged; Aged, 80 and over; Animals; Anti-Bacterial Agents; Bacteremia; Bacterial Proteins; Cefoxitin; Child, Preschool; DNA, Bacterial; Fatal Outcome; Female; Genotype; Humans; Male; Methicillin-Resistant Staphylococcus aureus; Microbial Sensitivity Tests; Middle Aged; Molecular Typing; Polymerase Chain Reaction; Spain; Staphylococcal Infections; Virulence Factors

The aim of this study was to investigate the prevalence and types of plasmid-mediated AmpC (pAmpC) beta-lactamase enzymes in Escherichia coli and Klebsiella pneumoniae strains isolated from blood cultures of hospitalized patients in Dokuz Eylul University Hospital between 2007 and 2012. A total of 261 isolates which consisted of 184 E.coli (70.5%) and 77 K.pneumoniae (29.5%) were included in the study. All isolates were resistant to cefotaxime and/or ceftazidime but susceptible to imipenem. Cefoxitin resistance was investigated as an indicator of AmpC type enzymes. A total of 57 (21.8%) isolates which were cefoxitin-resistant (32 E.coli, 25 K.pneumoniae), were screened for pampC genes by a multiplex polymerase chain reaction (PCR) assay. Additionally, 10 of each cefoxitin susceptible isolates per year were chosen randomly and screened by the same PCR assay to detect the presence of ACC enzymes, which can not hydrolyze cefoxitin. Positive PCR results were confirmed by sequence analysis. Plasmid analysis and macrorestriction analysis were performed for pampC-positive isolates. The presence of pAmpC enzymes has been shown in 9.4% (3/32) of cefoxitin-resistant E.coli, and 8% (2/25) of cefoxitin-resistant K.pneumoniae strains. It was noted that there were no strains producing this enzyme isolated in 2007 and 2008, however the prevalence of pAmpC was detected as 1.6% in 2009 (one ACT-1 producing K.pneumoniae), increasing to 4.8% in 2011 (one ACT-1 producing K.pneumoniae) and 6.4% in 2012 (three CMY-2 producing E.coli). These enzymes were found to be carried on 81 kb size plasmids in K.pneumoniae isolates and on a 9 kb size plasmid in E.coli isolates. Macrorestriction analysis indicated that two of the three CMY-2 producing E.coli had the same PFGE (Pulsed-field gel electrophoresis) pattern. If these two strains are considered as identical, it can be concluded that the prevalence of pAmpC was low in the strains isolated between 2007-2012 (4/261; 1.5%) in our institution. On the other hand, the increasing prevalence of pAmpC in 2011 and 2012 should be considered as a warning for the implementation of infection control measures and monitorization of the prevalence in order to prevent the dissemination of pAmpC. As far as the current literature is concerned, this is the first study that demonstrated the presence of the ACT-1 enzyme in K.pneumoniae isolates in Turkey.

Topics: Anti-Bacterial Agents; Bacteremia; Bacterial Proteins; beta-Lactamases; Cefotaxime; Cefoxitin; Ceftazidime; Drug Resistance, Multiple, Bacterial; Escherichia coli; Escherichia coli Infections; Humans; Imipenem; Klebsiella Infections; Klebsiella pneumoniae; Plasmids

Topics: Aged; Anti-Bacterial Agents; Bacteremia; Bacterial Proteins; beta-Lactam Resistance; beta-Lactamases; Catheter-Related Infections; Cefoxitin; Cross Infection; Diarrhea; Drug Resistance, Multiple, Bacterial; Drug Therapy, Combination; Enterococcus faecalis; Glycopeptides; Humans; Klebsiella Infections; Klebsiella pneumoniae; Male; Pancreatic Neoplasms; Pneumonia, Bacterial; Postoperative Complications; Prostatitis; Substrate Specificity; Urinary Catheterization

A novel Klebsiella pneumoniae carbapenemase (KPC) variant, designated bla(KPC-5), was discovered in a carbapenem-resistant Pseudomonas aeruginosa clinical isolate from Puerto Rico. Characterization of the upstream region of bla(KPC-5) showed significant differences from the flanking regions of other bla(KPC) variants. Comparison of amino acid sequences with those of other KPC enzymes revealed that KPC-5 was an intermediate between KPC-2 and KPC-4, differing from KPC-2 by a single amino acid substitution (Pro(103)-->Arg), while KPC-4 contained Pro(103)-->Arg plus an additional amino acid change (Val(239)-->Gly). Transformation studies with an Escherichia coli recipient strain showed differences in the properties of the KPC variants. KPC-4 and KPC-5 both had pIs of 7.65, in contrast with the pI of 6.7 for KPC-2. KPC-2 transformants were less susceptible to the carbapenems than KPC-4 and KPC-5 transformants. These data correlated with higher rates of imipenem hydrolysis for KPC-2 than for KPC-4 and KPC-5. However, KPC-4 and KPC-5 transformants had higher ceftazidime MICs, and the enzymes from these transformants had slightly better hydrolysis of this drug than KPC-2. KPC-4 and KPC-5 were more sensitive than KPC-2 to inhibition by clavulanic acid in both susceptibility testing and hydrolysis assays. Thus, KPC enzymes may be evolving through stepwise mutations to alter their spectra of activity.

Topics: Amino Acid Substitution; Anti-Bacterial Agents; Bacteremia; beta-Lactamase Inhibitors; beta-Lactamases; Clavulanic Acid; Drug Resistance, Bacterial; Enzyme Inhibitors; Genetic Variation; Hydrolysis; Isoelectric Focusing; Klebsiella pneumoniae; Microbial Sensitivity Tests; Phenotype; Protein Isoforms; Reverse Transcriptase Polymerase Chain Reaction

A total of 276 blood culture bottles with Staphylococcus aureus were tested by direct cefoxitin disk diffusion testing; 105 (38.1%) had zone sizes of /=21 mm (all 137 had MSSA). Detection of MRSA/MSSA in blood cultures could be reported 10 to 24 h earlier for 88% of cultures with total accuracy.

Topics: Aged; Aged, 80 and over; Anti-Bacterial Agents; Bacteremia; Blood; Cefoxitin; Diffusion; Humans; Methicillin Resistance; Microbial Sensitivity Tests; Sensitivity and Specificity; Staphylococcal Infections; Staphylococcus aureus

Bloodstream infections (BSI) caused by extended-spectrum beta-lactamase (ESBL)-producing organisms markedly increase the rates of treatment failure and death. We conducted a retrospective cohort analysis to identify risk factors for mortality in adult in-patients with BSI caused by ESBL-producing Enterobacteriaceae (ESBL-BSI). Particular attention was focused on defining the impact on the mortality of inadequate initial antimicrobial therapy (defined as the initiation of treatment with active antimicrobial agents >72 h after collection of the first positive blood culture). A total of 186 patients with ESBL-BSI caused by Escherichia coli (n = 104), Klebsiella pneumoniae (n = 58), or Proteus mirabilis (n = 24) were identified by our microbiology laboratory from 1 January 1999 through 31 December 2004. The overall 21-day mortality rate was 38.2% (71 of 186). In multivariate analysis, significant predictors of mortality were inadequate initial antimicrobial therapy (odds ratio [OR] = 6.28; 95% confidence interval [CI] = 3.18 to 12.42; P < 0.001) and unidentified primary infection site (OR = 2.69; 95% CI = 1.38 to 5.27; P = 0.004). The inadequately treated patients (89 of 186 [47.8%]) had a threefold increase in mortality compared to the adequately treated group (59.5% versus 18.5%; OR = 2.38; 95% CI = 1.76 to 3.22; P < 0.001). The regimens most commonly classified as inadequate were based on oxyimino cephalosporin or fluoroquinolone therapy. Prompt initiation of effective antimicrobial treatment is essential in patients with ESBL-BSI, and empirical decisions must be based on a sound knowledge of the local distribution of pathogens and their susceptibility patterns.

Topics: Adult; Aged; Anti-Bacterial Agents; Bacteremia; beta-Lactamases; Cross Infection; Drug Resistance, Bacterial; Enterobacteriaceae; Enterobacteriaceae Infections; Escherichia coli; Female; Humans; Klebsiella pneumoniae; Male; Microbial Sensitivity Tests; Middle Aged; Predictive Value of Tests; Proteus mirabilis; Risk Factors; Survival Analysis; Treatment Outcome

Peptostreptococcus anaerobius sensu lato, currently including two closely related species, P. anaerobius and P. stomatis, is known to be more resistant than other gram-positive anaerobic cocci. We reidentified potential Peptostreptococcus isolates and tested their susceptibilities to eight antimicrobials. Notably, P. anaerobius had constantly higher values for the MIC at which 50% of the isolates are inhibited (MIC(50)) and the MIC(90) than P. stomatis.

Topics: Anaerobiosis; Anti-Bacterial Agents; Bacteremia; Gram-Positive Bacterial Infections; Humans; Microbial Sensitivity Tests; Peptostreptococcus; Species Specificity

A prospective observational study was conducted to identify factors associated with bloodstream infections (BSIs) caused by integron-carrying Enterobacteriaceae and to evaluate the clinical significance of integron carriage. Consecutive patients with Enterobacteriaceae BSIs were identified and followed up until discharge or death. Identification of blood isolates and susceptibility testing were performed by the Wider I automated system. int-1-specific PCR, conserved-segment PCR, and DNA sequencing were used to determine the presence, length, and content of integrons. The relatedness among the isolates was examined by pulsed-field gel electrophoresis. Two hundred fifty episodes of Enterobacteriaceae BSI occurred in 233 patients; 109 (43.6%) were nosocomial, 82 (32.8%) were community acquired, and 59 (23.6%) were health care associated. Integrons were detected in 11 (13.4%) community-acquired, 24 (40.7%) health care-associated, and 46 (42.2%) nosocomial isolates. Integron-carrying organisms were more likely to exhibit resistance to three or more classes of antimicrobials (odds ratio [OR], 9.84; 95% confidence interval [95% CI], 5.31 to 18.23; P < 0.001) or to produce extended-spectrum beta-lactamases (OR, 5.75; 95% CI, 2.38 to 13.89; P < 0.001) or a VIM-type metallo-beta-lactamase (P, 0.003). Inter- or intraspecies integron transfer and cross-transmission of integron-carrying clones were observed. Use of cotrimoxazole (OR, 4.77; 95% CI, 1.81 to 12.54; P < 0.001) and a nosocomial or other health care setting (OR, 3.07; 95% CI, 1.30 to 7.22; P, 0.01) were independently associated with BSIs caused by integron-carrying Enterobacteriaceae. Patients with a nonurinary source of bacteremia (OR, 9.46; 95% CI, 2.77 to 32.32; P < 0.001) and a Pitt bacteremia score of > or =4 (OR, 23.36; 95% CI, 7.97 to 68.44; P < 0.001) had a significantly higher 14-day mortality rate, whereas integron carriage did not affect clinical outcomes. These findings may have implications affecting antibiotic policies and infection control measures.

Topics: Bacteremia; Community-Acquired Infections; Cross Infection; DNA, Bacterial; Drug Resistance, Multiple, Bacterial; Electrophoresis, Gel, Pulsed-Field; Enterobacteriaceae Infections; Gene Transfer, Horizontal; Humans; Infectious Disease Transmission, Professional-to-Patient; Integrons; Microbial Sensitivity Tests; Nucleic Acid Amplification Techniques; Polymerase Chain Reaction; Prospective Studies; Risk Factors; Sequence Analysis, DNA; Treatment Outcome

Topics: Adult; Amikacin; Anti-Bacterial Agents; Bacteremia; Catheterization, Central Venous; Catheters, Indwelling; Cefoxitin; Device Removal; Female; Humans; Leukemia; Lymphoma; Male; Middle Aged; Multiple Myeloma; Mycobacterium; Mycobacterium Infections; Retrospective Studies

Ingested foreign bodies rarely cause gastrointestinal perforation, because the majority are passed out uneventfully in the feces. However, long, sharp, slender, hard, indigestible objects such as toothpicks are dangerous and may lead to potentially life-threatening complications. We report a case of duodenal perforation caused by a toothpick and complicated by liver abscess and methicillin-resistant Staphylococcus aureus sepsis. Although laparotomy was not performed because of the patient's refusal to undergo surgery, the liver abscess and sepsis were controlled successfully with antibiotics. We also conducted a literature search for reports on injuries caused by ingested toothpicks.

Topics: Anti-Bacterial Agents; Anti-Infective Agents; Bacteremia; Cefoxitin; Duodenum; Follow-Up Studies; Foreign-Body Migration; Humans; Intestinal Perforation; Liver; Liver Abscess; Male; Methicillin Resistance; Metronidazole; Middle Aged; Staphylococcal Infections; Tomography, X-Ray Computed; Ultrasonography; Vancomycin

Continuous and twice-daily cefoxitin dosing was used in a highly lethal model of acute peritonitis in mice using intraperitoneal (IP) Klebsiella pneumoniae (Kpn). The purpose was to use antibiotics to create a model of chronic infection. Male Balb/c mice (averaging 20 g body weight) were inoculated IP with 10(3) colony-forming units (CFU) Kpn serotype 2. Controls received subcutaneous saline either twice daily or continuously. Antibiotic groups received 300 mg/kg per day of cefoxitin either twice daily or continuously. Survival and daily weight losses were determined. Another group was inoculated with 10(3) Kpn given twice daily saline or cefoxitin and harvested at 24 hours. Leukocyte counts were performed on peritoneal exudate cells (PEC) and peripheral blood. Cultures determined Kpn counts in blood, lung, and PEC. By 24 hours, saline-treated animals had lost more weight than cefoxitin mice (1 g vs. 2 g, P < 0.05). Continuous cefoxitin showed significant advantage with 50 per cent mortality at 5 days. Kpn levels were not significantly altered by cefoxitin. Cefoxitin treatment extended chronicity by preventing weight loss and increasing survival in a highly lethal, monomicrobial peritonitis model. This model will allow future study of specific host defense mechanisms over a prolonged time period.

Topics: Animals; Anti-Bacterial Agents; Ascitic Fluid; Bacteremia; Cefoxitin; Chronic Disease; Colony Count, Microbial; Disease Models, Animal; Injections, Subcutaneous; Klebsiella Infections; Klebsiella pneumoniae; Leukocyte Count; Lung; Male; Mice; Mice, Inbred BALB C; Neutrophils; Peritonitis; Random Allocation; Serotyping; Survival Rate; Weight Loss

Coagulase-negative staphylococci (CoNS) are a significant cause of nosocomial bacteraemia and their susceptibility to beta-lactamase-stabile penicillins is unpredictable. To ensure appropriate antibiotic therapy reliable methods for detection of methicillin resistance (MR) are needed. The objectives of this study were to determine the frequency of MR in a set of CoNS from cases of monomicrobial bacteraemia and to evaluate two phenotypic assays for detection of MR, the 10 microg cefoxitin disk test on Iso-Sensitest agar using a semiconfluent inoculum and the oxacillin Etest. MR was determined by a commercial genomic mecA assay. Of 110 CoNS, 75 were mecA positive and 35 mecA negative. Using interpretive zone diameters R < 22 mm and S > or = 27 mm, the cefoxitin disk test had a sensitivity and specificity of 100%. A correct prediction was obtained for 86 isolates, while 23 were indeterminate (> or = 22 mm; <27 mm). Using CLSI's guidelines, sensitivity and specificity of the oxacillin Etest were 100% and 80%, respectively. A correct prediction was obtained for 102 isolates, while 7 mecA negative isolates were classified as resistant. Thus, the cefoxitin disk test and the oxacillin Etest performed with high accuracy and both seem to be suitable for routine use.

Topics: Anti-Bacterial Agents; Bacteremia; Bacterial Proteins; Cefoxitin; Coagulase; Humans; Methicillin; Methicillin Resistance; Microbial Sensitivity Tests; Oxacillin; Penicillin-Binding Proteins; Sensitivity and Specificity; Staphylococcal Infections; Staphylococcus

Edwardsiella tarda (E. tarda) has recently become recognized as a pathogen in humans. Here we report a new case of E. tarda bacteraemia complicated by acute pancreatitis and pyomyoma. A 46-year-old female came to our emergency room complaining of sudden onset of left upper quadrant pain and vomiting for the previous few hours after drinking three bottles of wine. An abdominal computed tomography (CT) scan revealed multiple biliary stones, acute pancreatitis with extensive inflammatory change, and a large uterine myoma. Fever, watery diarrhoea, and mild suprapubic discomfort with vaginal spotting were noted soon after admission. The patient's blood cultures yielded E. tarda and symptoms subsided after antibiotic therapy. Fever and severe suprapubic pain with rebound tenderness developed 12 days later. Repeat abdominal CT scan revealed an enlarged uterine myoma with central necrosis. The patient subsequently underwent anterior total hysterectomy and bilateral salpingo-oophorectomy, revealing a uterine myoma with infarction and abscess formation. The patient recovered uneventfully and was discharged 1 week later.

Topics: Acute Disease; Amikacin; Anti-Bacterial Agents; Bacteremia; Blood Chemical Analysis; Cefoxitin; Cephamycins; Female; Gram-Negative Bacteria; Gram-Negative Bacterial Infections; Humans; Hysterectomy; Middle Aged; Myoma; Ovariectomy; Pancreatitis; Tomography, X-Ray Computed; Uterus

The effects of free versus liposomal cefoxitin on various physiological parameters in a porcine model of Gram-negative intra-abdominal sepsis were evaluated. Four different doses of Escherichia coli inoculum mixed with sterile pig feces were used (10(8), 10(9), 10(10), and 10(11) cfu/animal), and the most consistent hemodynamic changes were observed with an inoculum of approximately 10(11) bacteria/20 kg animal. Two treatment groups were established as follows: free cefoxitin (n = 9) and liposomal cefoxitin (n = 9). All animals were maintained under anesthesia for the duration of the study, and then euthanized 24 h following intra-abdominal inoculation. The inoculated and nontreated animals showed increases in heart rate, mean pulmonary arterial pressure, systemic and pulmonary vascular resistance, and decreases in mean systemic arterial pressure and cardiac index. These changes were significant (p < .05) compared with a control group injected with normal saline. Liposomal cefoxitin-treated animals showed significantly lower decreases in mean systemic arterial pressure and increases in heart rate (p < .05) compared with both the inoculated nontreated and free cefoxitin-treated groups. Both liposomal and free cefoxitin significantly modulated the mean pulmonary arterial pressure compared with the inoculated nontreated animals (p < .05). Acidosis that developed during intra-abdominal infection diminished 6 h following the first dose of liposomal cefoxitin (p < .05). The results of these experiments demonstrate that liposomal cefoxitin exerts a beneficial modulation of some of the hemodynamic disturbances during intra-abdominal Gram-negative sepsis.

Topics: Abdomen; Animals; Bacteremia; Blood Pressure; Cardiac Output; Cefoxitin; Drug Carriers; Escherichia coli Infections; Heart Rate; Hemodynamics; Liposomes; Male; Swine; Vascular Resistance

A study was performed to find an ideal combination and sequence of cytokines, antibiotics and immunorestorative agents to enhance survival from serious infection. The effects of combinations of granulocyte-macrophage colony-stimulating factor (GM-CSF), tumour necrosis factor (TNF) alpha, the immune adjuvant muramyl dipeptide (MDP) and two systemic antibiotics were studied in a validated murine model of surgical infection. A single cotton suture containing absorbed Klebsiella pneumoniae was placed into the thighs of mice to produce local and systemic infection. Control mice received a volume of subcutaneous saline equal to that of the therapeutic agent; only 18 per cent survived 9 days after infection. The survival time of mice treated with any single agent was similar to that of controls. The group given maximal combined therapy (65 mice) received GM-CSF, TNF-alpha, MDP, and ampicillin-sulbactam or cefoxitin for 6 days. The survival rate in this group 9 days after the introduction of infection was 84-90 per cent (P < 0.0001), suggesting that specific combinations of cytokines, immunostimulants and antibiotics may be useful in combating lethal infection.

Topics: Acetylmuramyl-Alanyl-Isoglutamine; Ampicillin; Animals; Bacteremia; Cefoxitin; Drug Therapy, Combination; Granulocyte-Macrophage Colony-Stimulating Factor; Klebsiella Infections; Mice; Sulbactam; Surgical Wound Infection; Tumor Necrosis Factor-alpha

Topics: Adolescent; Arthritis, Infectious; Bacteremia; Cefoxitin; Clindamycin; Fusobacterium Infections; Fusobacterium necrophorum; Humans; Jugular Veins; Male; Metronidazole; Peritonsillar Abscess; Pharyngitis; Syndrome; Thrombophlebitis