Antimicrobial resistance is one of the critical public health issues in the world. There is an urgent need to develop effective broad-spectrum antibiotics to treat the infection of multi-drug resistant Gram-negative bacilli. Cefiderocol, developed by the Shionogi Inc. in Japan, is a new type of iron carrier cephalosporin antibiotics, which overcomes the drug resistance of Gram-negative bacilli due to the down-regulation of outer membrane pore protein and the up-regulation of efflux pump, and has good stability to serine- and metallo-carbapenemases. This drug has a broad spectrum and strong antibacterial activity against carbapenem-resistant Enterobacteriaceae (CRE), Pseudomonas aeruginosa, Acinetobacter baumannii, and Stenotrophomonas maltophilia. Cefiderocol can be used to treat complex urinary tract infections (including pyelonephritis), hospital-acquired pneumonia, and ventilator-associated pneumonia. By summarizing the chemical structure, antibacterial mechanism, in vitro antibacterial activity, pharmacokinetics, pharmacodynamics, and clinical treatment of cefiderocol, this review shows the application potential of cefiderocol as a new iron carrier cephalosporin in the treatment of multi-drug resistant Gram-negative bacilli infections.
Cephalosporins/therapeutic use* ; Gram-Negative Bacteria ; Microbial Sensitivity Tests ; Siderophores/pharmacology*

OBJECTIVES: To investigate the changes in the pathogen spectrum and antimicrobial resistance over time in neonatal sepsis. METHODS: The medical data were collected from the neonates who were diagnosed with sepsis in the Second Xiangya Hospital of Central South University from January 2010 to December 2019. The incidence rate of sepsis, the pathogen spectrum, and the characteristics of antimicrobial resistance were analyzed. RESULTS: The incidence rate of neonatal sepsis was 4.02% (447/11 111). The top four pathogens detected were coagulase-negative staphylococci (CoNS), Klebsiella pneumoniae, Escherichia coli, and Candida. The incidence rate of sepsis and the pathogen spectrum showed no significant changes over time. Klebsiella pneumoniae was the most frequent pathogen in preterm infants, very low birth weight infants, and small-for-gestational-age infants, accounting for 33.9%, 29.5%, and 42.5%, respectively. CoNS, Klebsiella pneumoniae, and Escherichia coli had a high resistance rate to penicillins and third-generation cephalosporins. CONCLUSIONS The incidence of neonatal sepsis is high, and the main pathogen is CoNS. The pathogens of neonatal sepsis have a high resistance rate to penicillins and third-generation cephalosporins. It is recommended to enhance the prevention and control of neonatal infection, strengthen the surveillance of pathogens, and further standardize the rational use of antibiotics.
Infant ; Infant, Newborn ; Humans ; Neonatal Sepsis/etiology* ; Anti-Bacterial Agents/therapeutic use* ; Microbial Sensitivity Tests ; Retrospective Studies ; Drug Resistance, Bacterial ; Infant, Premature ; Sepsis/complications* ; Escherichia coli ; Cephalosporins ; Penicillins

OBJECTIVES: This study aimed to understand the nationwide patterns of antibiotic prescription after tooth extraction in adult patients.MATERIALS AND METHODS: This study analyzed dental records from the National Health Insurance Service–National Sample Cohort (NHIS–NSC) database on 503,725 tooth extractions performed in adults (≥19 years) during 2011–2015. Patient sex, age, household income, systemic disease (diabetes mellitus and hypertension), type of dental institution, region of dental institution, year of prescription, and type of tooth extraction procedure were considered. The antibiotic prescription rate and broad-spectrum antibiotic prescription frequency were analyzed using chi-squared tests. Factors affecting the prescription of broad-spectrum antibiotics were evaluated using multivariate logistic regression analysis.RESULTS: The rate of antibiotic prescription after tooth extraction was 81.85%. Penicillin was most commonly prescribed (45.25%), followed by penicillin with beta-lactamase inhibitors (18.76%), metronidazole (12.29%), and second- to fourth-generation cephalosporins (11.52%). The proportion of broad-spectrum antibiotics used among all prescribed antibiotics was 45.88%.CONCLUSION: The findings of this study demonstrate that the rate of antibiotic prescription after tooth extraction is higher in Korea than in other countries. Furthermore, broad-spectrum antibiotics are used more frequently, which may indicate unnecessary drug prescription, an important contributor to antibiotic resistance.
Adult ; Anti-Bacterial Agents ; beta-Lactamase Inhibitors ; Cephalosporins ; Cohort Studies ; Dental Records ; Drug Prescriptions ; Drug Resistance, Microbial ; Family Characteristics ; Humans ; Korea ; Logistic Models ; Metronidazole ; National Health Programs ; Penicillins ; Prescriptions ; Tooth Extraction ; Tooth

PURPOSE: A task force appointed by the Korean Society of Acute Care Surgery reviewed previously published guidelines on antibiotic use in patients with abdominal injuries and adapted guidelines for Korea. METHODS: Four guidelines were assessed using the Appraisal of Guidelines for Research and Evaluation II instrument. Five topics were considered: indication for antibiotics, time until first antibiotic use, antibiotic therapy duration, appropriate antibiotics, and antibiotic use in abdominal trauma patients with hemorrhagic shock. RESULTS: Patients requiring surgery need preoperative prophylactic antibiotics. Patients who do not require surgery do not need antibiotics. Antibiotics should be administered as soon as possible after injury. In the absence of hollow viscus injury, no additional antibiotic doses are needed. If hollow viscus injury is repaired within 12 hours, antibiotics should be continued for ≤ 24 hours. If hollow viscus injury is repaired after 12 hours, antibiotics should be limited to 7 days. Antibiotics can be administered for ≥7 days if hollow viscus injury is incompletely repaired or clinical signs persist. Broad-spectrum aerobic and anaerobic coverage antibiotics are preferred as the initial antibiotics. Second-generation cephalosporins are the recommended initial antibiotics. Third-generation cephalosporins are alternative choices. For hemorrhagic shock, the antibiotic dose may be increased twofold or threefold and repeated after transfusion of every 10 units of blood until there is no further blood loss. CONCLUSION: Although this guideline was drafted through adaptation of other guidelines, it may be meaningful in that it provides a consensus on the use of antibiotics in abdominal trauma patients in Korea.
Abdominal Injuries* ; Advisory Committees ; Anti-Bacterial Agents ; Antibiotic Prophylaxis ; Cephalosporins ; Consensus ; Humans ; Korea ; Shock, Hemorrhagic

BACKGROUND: Escherichia coli and Klebsiella pneumoniae clinical isolates producing CTX-M extendedspectrum β-lactamases (ESBLs) were assessed for antimicrobial resistance phenotypes varied by group of enzymes. METHODS: A total of 1,338 blood isolates, including 959 E. coli and 379 K. pneumoniae, were studied. All the strains were collected between January and July 2017 from eight general hospitals in South Korea. The species were identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry. Antimicrobial susceptibilities were determined by disk diffusion methods and ESBL phenotypes by double-disk synergy tests using disks containing cefotaxime, ceftazidime, cefepime, aztreonam, and clavulanic acid (CA). The genes for β-lactamases were identified by PCR and sequencing. RESULTS: Of total microbes, 31.6% (303/959) E. coli and 24.0% (91/379) K. pneumoniae were resistant to cefotaxime and 28.1% (269/959) E. coli and 20.1% (76/379) K. pneumoniae were CTX-M-type ESBL producers. Among the detected CTX-M ESBLs, 58.0% (156/269) in E. coli and 86.8% (66/76) in K. pneumoniae belonged to group 1, 46.8% (126/269) in E. coli and 14.5% (11/76) in K. pneumoniae were group 9. Ten E. coli and one K. pneumoniae isolates co-produced both groups of CTX-M ESBL. The group 1 CTX-M producers had a higher level of resistance to cefotaxime, ceftazidime, cefepime, and aztreonam and exhibited stronger synergistic activities when combined with CA compared to group 9. CONCLUSION: ESBL phenotypes differ by CTX-M ESBL group and phenotype testing with drugs including 4th generation cephalosporins and monobactams is critical for screening CTX-M-producers with better sensitivity.
Aztreonam ; Cefotaxime ; Ceftazidime ; Cephalosporins ; Clavulanic Acid ; Diffusion ; Escherichia coli ; Hospitals, General ; Klebsiella pneumoniae ; Korea ; Mass Screening ; Mass Spectrometry ; Monobactams ; Phenotype ; Pneumonia ; Polymerase Chain Reaction

cephalosporins, and ciprofloxacin should be considered when determining empirical antibiotic therapy in clinical practice.]]>
Acinetobacter ; Amikacin ; Ampicillin ; Anti-Bacterial Agents ; Cefotaxime ; Ceftazidime ; Cephalosporins ; Ciprofloxacin ; Cross Infection ; Enterococcus ; Epidemiology ; Escherichia coli ; Humans ; Imipenem ; Intraabdominal Infections ; Klebsiella ; Korea ; Peritoneal Dialysis, Continuous Ambulatory ; Peritonitis ; Pseudomonas aeruginosa ; Retrospective Studies ; Vancomycin

BACKGROUND: Although guidelines to prevent surgical site infections (SSIs) were published more than a decade ago, prophylactic antibiotics are still used subjectively in clinical practice. In this study, we evaluated the safety of single-dose preoperative intravenous antibiotics without postoperative antibiotics in the field of clean wound surgery performed under local anesthesia. We also surveyed the present clinical conditions for prophylactic antibiotic use in the plastic surgery departments of training hospitals in Korea. METHODS: A total of 360 consecutive patients who underwent clean wound surgery under local anesthesia in an outpatient clinic from March 2018 to October 2018 were reviewed. In the study group, a single surgeon administered first-generation cephalosporins intravenously within 1 hour of skin incision and did not prescribe additional antibiotics. In the control group, 2 other surgeons prescribed oral first-generation cephalosporins postoperatively for 2 to 3 days without preoperative antibiotics. A telephone survey about perioperative antibiotic regimens was conducted at the departments of plastic surgery in training hospitals. RESULTS: There were 128 patients in the study group and 232 patients in the control group. There were no significant differences between the 2 groups regarding SSIs and other surgical complications. A total of 41 training hospitals answered the survey and every hospital had protocols of prescribing postoperative oral antibiotics routinely at the time of discharge with a mean duration of 3.9 days. Only 11 hospitals (26.8%) prescribed parenteral antibiotics before surgery as well as postoperative oral antibiotics. CONCLUSION: Intravenous injection of single-dose first-generation cephalosporins 1 hour before surgery without postoperative antibiotics did not increase the incidence of SSIs compared with the usual practice of giving only postoperative antibiotics prescription for 2 to 3 days in cases of clean wound surgery performed under local anesthesia. Proper antibiotic prophylaxis should be performed by surgeons in training hospitals without hesitation.
Ambulatory Care Facilities ; Anesthesia, Local ; Anti-Bacterial Agents ; Antibiotic Prophylaxis ; Cephalosporins ; Humans ; Incidence ; Injections, Intravenous ; Korea ; Prescriptions ; Skin ; Surgeons ; Surgery, Plastic ; Surgical Wound Infection ; Telephone ; Wounds and Injuries

Salmonella enterica serovar Typhimurium is one of the most important bacterial pathogens causing diarrhea. The resistance of S. typhimurium to antimicrobial agents, which has recently been isolated from patients, is causing serious problems. We investigated the effects of salicylic acid (Sal) and acetyl salicylate (AcSal) on the susceptibility of S. typhimurium to cephalosporin antibiotics, which are known to increase resistance to cephalosporin and quinolone antibiotics. The MIC of cephalosporin antibiotics was higher than that of the media without Sal. The rate of accumulation of ethidium bromide (EtBr) in the bacteria by the outer membrane protein (Omp) was not different from that of the bacteria cultured in the medium containing Sal. However, Carbonyl cyanide-m-chlorophenylhydrazone (CCCP), an inhibitor of bacterial efflux pumps, significantly reduced the rate of accumulation of EtBr in bacteria cultured on Sal containing medium. In the medium containing CCCP, the MIC of the antimicrobial agent tended to decrease as compared with the control. In addition, the MIC of the bacteria treated with CCCP and Sal was higher than that of the antimicrobial agent against the CCCP treated experimental bacteria. These results suggest that Sal decreases the expression of OmpF in the Omp of S. typhimurium and reduces the permeability of cephalosporin antibiotics to bacteria, which may induce tolerance to cephalosporin antibiotics.
Anti-Bacterial Agents ; Anti-Infective Agents ; Bacteria ; Carbonyl Cyanide m-Chlorophenyl Hydrazone ; Cephalosporin Resistance ; Cephalosporins ; Diarrhea ; Ethidium ; Humans ; Membrane Proteins ; Permeability ; Salicylic Acid ; Salmonella enterica ; Salmonella typhimurium ; Salmonella ; Serogroup

Gonococcal conjunctivitis is rare in adults and, if not treated properly, can cause corneal perforation. Gonococcal conjunctivitis typically presents with a severe mucopurulent discharge, similar to that associated with viral conjunctivitis. Here, we describe a case of monocular gonococcal conjunctivitis, including its clinical characteristics and slit-lamp images, which was initially misdiagnosed as epidemic conjunctivitis. A 20-year-old man was referred to our hospital with no improvement in monocular infection and purulent ocular discharge after 2-wk treatment using antibiotic and 0.1% fluorometholone eye drops at the local ophthalmic clinic. Initially, 0.5% loteprednol eye drops were used since we suspected viral conjunctivitis. Following this treatment, conjunctival infection worsened and a yellow-white ocular discharge covered the conjunctiva and cornea surface. Additional history taking revealed that the patient had sexual contact with a prostitute 1 wk prior to symptom presentation and, after the encounter, he took antibiotics for genital discharge at the local urology clinic, but self-discontinued treatment. A Gram staining showed gram-negative diplococci and culture of collected ocular discharge from the palpebral conjunctiva revealed growth of Neisseria gonorrhoeae, confirming gonococcal conjunctivitis. Following this, the patient was systemically treated with 3rd generation cephalosporin antibiotics. After 3-d treatment, conjunctival infection and purulent ocular discharge had significantly improved. When clinical symptoms are aggravated following steroid eye drop treatment for suspected monocular viral conjunctivitis, gonococcal conjunctivitis must be considered as a differential diagnosis
Adult* ; Anti-Bacterial Agents ; Cephalosporins ; Conjunctiva ; Conjunctivitis* ; Conjunctivitis, Viral ; Cornea ; Corneal Perforation ; Diagnosis, Differential ; Fluorometholone ; Humans ; Loteprednol Etabonate ; Male* ; Neisseria gonorrhoeae ; Ophthalmic Solutions ; Sex Workers ; Urology ; Young Adult

BACKGROUND: Bacterial skin infections occur secondarily in conditions involving a vulnerable skin barrier such as atopic eczema, as well as primarily such as impetigo. They are mainly caused by Staphylococcus aureus and Streptococci. Recently, the prevalence of methicillin-resistant S. aureus has been increasing. OBJECTIVE: To determine the characteristics of community-acquired bacterial skin infections, to observe their antibiotic susceptibility patterns, and to evaluate factors contributing to the treatment response. METHODS: We retrospectively reviewed outpatients under 30 years old from 2010 to 2015, from whom we had taken skin swabs for antibiotic susceptibility testing. We collected clinical and microbiological characteristics from the medical records. RESULTS: We evaluated the culture results of 197 patients and reviewed their medical records. Overall, 86.3% (n=170) of the patients responded to the initial treatment regimen. S. aureus was the most commonly isolated pathogen (52.6%) and showed a high resistance rate to penicillin (90.9%) and oxacillin (36.3%). In the multivariable logistic regression analysis, resistance to 3 or more antibiotics (p=0.044), culture amounts described as “many” (p=0.040), and non-systemic antibiotic use (p < 0.001) were significantly associated with lower treatment response. However, methicillin resistance was not associated with lower treatment response both in univariable and multivariable analyses. CONCLUSION: Among young patients, S. aureus was the most predominant pathogen present in bacterial skin infections. Resistance to high numbers of antibiotics and the use of non-systemic antibiotics were associated with lower treatment response. First-generation cephalosporins may be the most effective first-line empirical regimen for bacterial skin infections treated in outpatient settings, regardless of methicillin resistance.
Anti-Bacterial Agents ; Cephalosporins ; Dermatitis, Atopic ; Humans ; Impetigo ; Logistic Models ; Medical Records ; Methicillin Resistance ; Outpatients ; Oxacillin ; Penicillins ; Prevalence ; Retrospective Studies ; Skin Diseases, Infectious ; Skin* ; Staphylococcus aureus