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Medicine Jun 2020Methicillin-resistant Staphylococcus aureus (MRSA) has been established as an important cause of severe community-acquired pneumonia (CAP) with very high mortality....
RATIONALE
Methicillin-resistant Staphylococcus aureus (MRSA) has been established as an important cause of severe community-acquired pneumonia (CAP) with very high mortality. Panton-Valentine leukocidin (PVL) producing MRSA has been reported to be associated with necrotizing pneumonia and worse outcome. The incidence of community-acquired MRSA (CA-MRSA) pneumonia is very low, as only a few CA-MRSA pneumonia cases were reported in the last few years. We present a case of severe CAP caused by PVL-positive MRSA with ensuing septic shock.
PATIENT CONCERNS
A 68-year-old male with no concerning medical history had developed a fever that reached 39.0°C, a productive cough that was sustained for 5 days, and hypodynamia. He was treated with azithromycin and alexipyretic in a nearby clinic for 2 days in which the symptoms were alleviated. However, 1 day later, the symptoms worsened, and he was taken to a local Chinese medicine hospital for traditional medicine treatment. However, his clinical condition deteriorated rapidly, and he then developed dyspnea and hemoptysis.
DIAGNOSIS
CA-MRSA pneumonia and septic shock. The sputum culture showed MRSA. Polymerase chain reaction of MRSA isolates was positive for PVL genes.
INTERVENTIONS
Mechanical ventilation, fluid resuscitation, and antibiotic therapy were performed. Antibiotic therapy included mezlocillin sodium/sulbactam sodium, linezolid, and oseltamivir.
OUTCOMES
He died after 12 hours of treatment.
LESSONS
This is a report of severe pneumonia due to PVL-positive CA-MRSA in a healthy adult. CA-MRSA should be considered a pathogen of severe CAP, especially when combined with septic shock in previously healthy individuals.
Topics: Aged; Anti-Bacterial Agents; Cough; Healthcare-Associated Pneumonia; Humans; Hypokinesia; Linezolid; Male; Methicillin-Resistant Staphylococcus aureus; Mezlocillin; Oseltamivir; Shock, Septic; Staphylococcal Infections
PubMed: 32590802
DOI: 10.1097/MD.0000000000020914 -
BMC Pulmonary Medicine Feb 2020Descending necrotizing mediastinitis is a severe infection of the mediastinum. This syndrome manifests as fever and chest pain following cough and sputum production. A... (Review)
Review
Descending necrotizing mediastinitis is a severe infection of the mediastinum. This syndrome manifests as fever and chest pain following cough and sputum production. A 49-year-old woman presented with fever and a 14-day history of pneumonia. CT showed mediastinal abscesses with a giant calcified mediastinal lymph node (21 × 18 mm) and pneumonia. Bronchoscopy by EBUS-TBNA under general anesthesia was performed. The pathogen found in the puncture culture was Streptococcus constellatus, and antibiotics (mezlocillin/sulbactam 3.375 IVGTT q8h) was administered. A proximal right main bronchial neoplasm, suspected lung cancer, was found and conformed to inflammatory granuloma. A total of 22 months post-discharge the patient was clinically stable. We also conducted a review of the literature for all Streptococcus constellatus descending necrotizing mediastinitis infections between 2011 and 2017.
Topics: Anti-Bacterial Agents; Bronchoscopy; Drainage; Female; Humans; Immunocompetence; Lymph Nodes; Mediastinitis; Middle Aged; Pneumonia; Streptococcal Infections; Streptococcus constellatus; Tomography, X-Ray Computed
PubMed: 32066414
DOI: 10.1186/s12890-020-1068-3 -
Saudi Journal of Biological Sciences Nov 2019Antibiotic-resistant strains including extended-spectrum β-lactamase (ESBL) isolates are globally widespread in medical, food, and environmental sources. Some of these...
Antibiotic-resistant strains including extended-spectrum β-lactamase (ESBL) isolates are globally widespread in medical, food, and environmental sources. Some of these strains are considered the most pathogenic bacteria in humans. The present work examined the predominance of antibiotic resistance in strains in wound infections comparing with strains isolated from a raw milk as a potential source of those strains. The wound infections included abdomen, anus, arm, back, buttock, chest, foot, hand, head, leg, lung, mouth, neck, penis, thigh, toe, and vagina infections. In total, 161 and 153 isolates identified as were obtained from wound infections and raw milk, respectively. A Vitek 2 system innovated by bioMérieux, France was applied to perform the identification and susceptibility tests. The isolates that have ability to produce ESBL were detected by an ESBL panel and NO45 card (bioMérieux). Over half of the were from abdomen, back, and buttock wound infections. More than 50%of the isolates obtained from wound infections were resistant to cefazolin, ampicillin, cefuroxime, ciprofloxacin, mezlocillin, moxifloxacin, piperacillin, and tetracycline; 70% of the isolates from wound infections and 0% of the isolates from raw milk were isolates produced ESBL. The data showed that the strains resistance to multi-antibiotic and produced ESBL are more widespread among wound infections than in raw milk.
PubMed: 31762626
DOI: 10.1016/j.sjbs.2018.11.016 -
Rapid Communications in Mass... Sep 2019Eleven impurities and one polymerized impurity in mezlocillin were identified and their formation mechanisms were investigated in this study. The sources and reasons for...
Study of the impurity profile and polymerized impurity in mezlocillin sodium by multiple heart-cutting two-dimensional liquid chromatography coupled with ion trap time-of-flight mass spectrometry.
RATIONALE
Eleven impurities and one polymerized impurity in mezlocillin were identified and their formation mechanisms were investigated in this study. The sources and reasons for the formation of impurities were revealed, which may guide industry to improve the manufacturing process and storage conditions and reduce the content of impurities in products. The results from this study also provided a scientific basis for the improvement of official monographs in pharmacopoeias.
METHODS
The impurity profiles and polymerized impurity in mezlocillin were studied by multiple heart-cutting two-dimensional liquid chromatography coupled with ion trap time-of-flight mass spectrometry (2D-LC/IT-TOF MS) in both positive and negative modes of electrospray ionization. Target eluents from the first dimensional chromatography with a non-volatile mobile phase were trapped and sent to the second dimensional chromatography with a volatile mobile phase by a switching valve. The structures of the impurities in the mezlocillin drug substance were deduced based on the high-resolution MS data.
RESULTS
In the environment of water, oxygen, high temperature, acid and base, a series of degradation products could be easily produced from mezlocillin. Mezlocillin was hydrolyzed into impurities I, IV, V and X, and was degraded into impurity III by methanolysis. Mezlocillin was oxidized into sulfoxide by producing impurity XI. Furthermore, impurities VI, VII, VII and IX were all isomers of mezlocillin. The proposed formation pathways of these products were demonstrated in this study.
CONCLUSIONS
Eleven degradation impurities and one polymerized impurity in mezlocillin were separated and characterized. Based on characterization of impurities, this study discovered the mechanism of impurity production and provided guidance for manufacturers to improve the process and storage conditions and reduce levels of impurities.
PubMed: 31148276
DOI: 10.1002/rcm.8486 -
Medicine Nov 2018Pyoderma gangrenosum (PG) is a rare postoperative complication of enterostomy, mostly developing from dermatitis, which may have serious consequence.
RATIONALE
Pyoderma gangrenosum (PG) is a rare postoperative complication of enterostomy, mostly developing from dermatitis, which may have serious consequence.
PATIENT CONCERNS
A patient with lower rectal cancer receiving low anterior resection (LAR) and protective ileostomy was initially diagnosed with dermatitis, which very quickly developed to PG, though no medical or familial history was found.
DIAGNOSIS
We diagnosed the patient with peristoaml dermatitis starting from a tiny skin ulceration, but corrected the diagnosis to PG because of the rapid development and severe consequences.
INTERVENTIONS
Routine stoma care did not improve the condition, so we performed 2 terms of debridement, the closure of the stoma and autologous skin transplantation before finally solving the problem.
OUTCOMES
The patient was discharged 60 days after the first surgery and 5 days after the last one. After 18 months of follow-up, the patient kept in a stable condition.
LESSONS
Medical staff should not neglect peristoaml dermatitis because of its common occurrence. Once the situation develops beyond the doctors' expectation, more efforts should be made to treat it, even expand debridement if possible.
Topics: Anti-Bacterial Agents; Debridement; Humans; Ileostomy; Male; Mezlocillin; Middle Aged; Pyoderma Gangrenosum; Skin Transplantation; Transplantation, Autologous; Zinc Oxide
PubMed: 30508946
DOI: 10.1097/MD.0000000000013415 -
International Journal of Hygiene and... Jan 2019The retrieval of a polystyrene macro-plastic piece stranded on the shores in King George Island (South Shetlands, Antarctica) gave the opportunity to explore the...
Do plastics serve as a possible vector for the spread of antibiotic resistance? First insights from bacteria associated to a polystyrene piece from King George Island (Antarctica).
The retrieval of a polystyrene macro-plastic piece stranded on the shores in King George Island (South Shetlands, Antarctica) gave the opportunity to explore the associated bacterial flora. A total of 27 bacterial isolates were identified by molecular 16s rRNA gene sequencing and 7 strains were selected and screened for their ability to produce biofilm and antibiotic susceptibility profiles. All the bacterial isolates were able to produce biofilm. The Kirby-Bauer disk diffusion susceptibility test to 34 antibiotics showed multiple antibiotic resistances against the molecules cefuroxime and cefazolin (belonging to cephalosporins), cinoxacin (belonging to quinolones) and ampicillin, amoxicillin + clavulanic acid, carbenicillin and mezlocillin (belonging to beta-lactams). The obtained results suggest that plastics can serve as vectors for the spread of multiple resistances to antibiotics across Antarctic marine environments and underline the relevance of future studies on this topic.
Topics: Antarctic Regions; Drug Resistance, Bacterial; Environmental Microbiology; Polystyrenes
PubMed: 30174218
DOI: 10.1016/j.ijheh.2018.08.009 -
Current Drug Discovery Technologies 2020Uropathogenic Escherichia coli (UPEC) is a major cause of Urinary Tract Infections (UTIs). Due to increasing antibiotic-resistance among UPEC bacteria, new treatment...
BACKGROUND
Uropathogenic Escherichia coli (UPEC) is a major cause of Urinary Tract Infections (UTIs). Due to increasing antibiotic-resistance among UPEC bacteria, new treatment options for UTIs are urgently needed.
OBJECTIVE
To identify new agents targeting growing bacteria that may be used for the treatment of antibiotic-resistant UTIs.
METHODS
We screened a clinical compound library consisting of 1,524 compounds using a high throughput 96-well plate assay and ranked the activities of the selected agents according to their MICs against the UPEC strain UTI89.
RESULTS
We identified 33 antibiotics which were active against log-phase clinical UPEC strain UTI89. Among the selected antibiotics, there were 12 fluoroquinolone antibiotics (tosufloxacin, levofloxacin, sparfloxacin, clinafloxacin, pazufloxacin, gatifloxacin, enrofloxacin, lomefloxacin, norfloxacin, fleroxacin, flumequine, ciprofloxacin), 15 beta-lactam or cephalosporin antibiotics (cefmenoxime, cefotaxime, ceftizoxime, cefotiam, cefdinir, cefoperazone, cefpiramide, cefamandole, cefixime, ceftibuten, cefmetazole, cephalosporin C, aztreonam, piperacillintazobactam, mezlocillin), 3 tetracycline antibiotics (meclocycline, doxycycline, tetracycline), 2 membrane-acting agents (colistin and clofoctol), and 1 protein synthesis inhibitor (amikacin). Among them, the top 7 hits were colistin, tosufloxacin, levofloxacin, sparfloxacin, clinafloxacin, cefmenoxime and pazufloxacin, where clinafloxacin and pazufloxacin were the newly identified agents active against UPEC strain UTI89. We validated the key results obtained with UTI89 on two other UTI strains CFT073 and KTE181 and found that they all had comparable MICs for fluoroquinolones while CFT073 and KTE181 were more susceptible to cephalosporin antibiotics and tetracycline antibiotics but were less susceptible to colistin than UTI89.
CONCLUSION
Our findings provide possible effective drug candidates for the more effective treatment of antibiotic-resistant UTIs.
Topics: Anti-Bacterial Agents; Cell Proliferation; Drug Resistance, Bacterial; High-Throughput Screening Assays; Humans; Microbial Sensitivity Tests; Urinary Tract Infections; Uropathogenic Escherichia coli
PubMed: 30088449
DOI: 10.2174/1570163815666180808115501 -
Folia Microbiologica Nov 2018Aeromonads represent bacteria thought to be primarily mostly autochthonous to aquatic environments. This study was focused on the relation with antibiotics and...
Aeromonads represent bacteria thought to be primarily mostly autochthonous to aquatic environments. This study was focused on the relation with antibiotics and enterocins of identified Aeromonas species isolated from the intestine of trouts living in Slovakian aquatic sources. Intestinal samples from 50 trouts (3 Salmo trutta and 47 Salmo gairdnerii) were collected in April of years 2007, 2010, and 2015 from trouts of different water sources in Slovakia (pond Bukovec near Košice, river Čierny Váh). Due to the MALDI-TOF mass spectrometry evaluation, 25 strains were proposed to the genus Aeromonas involving nine different species (Aeromonas bestiarum-nine strains, Aer. salmonicida-four strains, Aer. encheleia, Aer. eucrenophila, Aer. molluscorum, Aer. media, Aer. sobria, Aer. popoffii, Aer. veronii). Phenotypic evaluation of individual strains confirmed their species identification. Twenty-five strains of different Aeromonas species were sensitive to azithromycin, amikacin, mecillinam, mezlocillin, piperacillin, gentamicin, chloramphenicol, and tetracycline. On the other side, they were resistant to carbenicillin and ticarcillin. The growth of Aer. bestiarum R41/1 was inhibited by treatment with Ent M and Ent 2019 (inhibition activity 100 AU/mL). Aer. bestiarum R47/3 was inhibited by eight enterocins (100 AU/mL). It is the first study testing enterocins to inhibit the growth of Aeromonas species from trouts.
Topics: Aeromonas; Animals; Anti-Bacterial Agents; Bridged-Ring Compounds; Fish Diseases; Genotype; Phenotype; Slovakia; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Trout
PubMed: 29808450
DOI: 10.1007/s12223-018-0616-1 -
Environmental Science and Pollution... Jan 2018Bacterial biofilm production is recognized as a strategy that helps aquatic bacteria in resisting to the presence of several kinds of pollutants, including antibiotics,...
Bacterial biofilm production is recognized as a strategy that helps aquatic bacteria in resisting to the presence of several kinds of pollutants, including antibiotics, in the bulk environment. The Pasvik River, located between Norway, Russia and Finland, is a sub-Arctic site polluted by wastes from metallurgic and mining activities. In order to study whether and to what extent bacteria are able to produce biofilms, and to assess whether this physiological characteristic influences their resistance to antibiotics, an investigation was performed on bacteria isolated from water and sediment collected along the Pasvik River course during two surveys (May and July). Bacterial strains were screened for their biofilm production and profiles of susceptibility to antibiotics. Results showed that biofilm formation was a widespread characteristic of the isolates. Most of them were also resistant to several antibiotics, such as ampicillin (100% of the isolates) as well as cefazolin, cefoxitin, ceftriaxone, mezlocillin, nitrofurantoin and sisomicin (90% of the total strains). This study shows a significant association between biofilm formation and antibiotic resistance at inner stations both in water and in sediments in May only. This suggests that in Pasvik River colder temperature may stimulate bacterial aggregation into biofilm and simultaneously decrease bacterial susceptibility to antibiotics; since the occurrence of antibiotic resistance has frequently been linked to the presence of pollutants, this result could represent a strategy of bacterial survival under altered environmental conditions.
Topics: Anti-Bacterial Agents; Arctic Regions; Bacteria; Bacterial Physiological Phenomena; Biofilms; Drug Resistance, Bacterial; Environment; Norway; Rivers
PubMed: 29079976
DOI: 10.1007/s11356-017-0485-1 -
Journal of Natural Science, Biology,... 2017has emerged as an important pathogen in hospital and environment that can acquire transport element and antibiotic-resistant genes. The aim of this study was to...
BACKGROUND AND OBJECTIVE
has emerged as an important pathogen in hospital and environment that can acquire transport element and antibiotic-resistant genes. The aim of this study was to determine the resistances to different antibiotics, frequency of Class 1 integron in and then molecular typing for isolated from Intensive Care Unit (ICU).
MATERIALS AND METHODS
A total of 100 isolates of were collected from patients admitted to hospitals in Kermanshah from April 2014 to September 2015. The isolates were identified using biochemical test. Antimicrobial susceptibility test for 20 antibiotics was determined by Kirby-Bauer antibiotic testing (or disc diffusion). The prevalence rate of class integrons among the isolates was determined using polymerase chain reaction and finally 80 isolates of obtained from the Intensive Care Unit were selected for molecular typing by pulsed-field gel electrophoresis (PFGE).
RESULTS
The maximum drug resistance was observed against cefotaxime, ceftriaxone, mezlocillin, imipenem, and ceftazidime and piperacillin. Twenty-nine isolates were multidrug resistant (MDR); about 21 isolates were extensively-drug resistant and none were pandrug resistance and 42 isolates (42%) contained Class 1 integrons. The results did not show a significant correlation between the presence of Class 1 integrons and incidence of MDR . Five clusters were obtained by PFGE.
CONCLUSION
This study did not show a significant correlation between the presence of Class 1 integrons and incidence of MDR . By PFGE analysis, the high level of similarity between some pulsotypes in strains showed genetic correlation between them.
PubMed: 28781486
DOI: 10.4103/0976-9668.210007