OBJECTIVE: To analyze the distribution and drug resistance of pathogens in oral mucositis associated with chemotherapy in hospitalized patients with malignant hematopathy, so as to provide scientific evidences for rational selection of antibiotics and infection prevention and control. METHODS: From July 2020 to June 2022, 167 patients with malignant hematopathy were treated with chemical drugs in the Department of Hematology, Hainan Hospital, and secretions from oral mucosal infected wounds were collected. VITEK2 COMPECT automatic microbial identification system (BioMerieux, France) and bacterial susceptibility card (BioMerieux) were used for bacterial identification and drug susceptibility tests. RESULTS: A total of 352 strains of pathogens were isolated from 167 patients, among which 220 strains of Gram-positive bacteria, 118 strains of Gram-negative bacteria and 14 strains of fungi, accounted for 62.50%, 33.52% and 3.98%, respectively. The Gram-positive bacteria was mainly Staphylococcus and Streptococcus, while Gram-negative bacteria was mainly Klebsiella and Proteus. The resistance of main Gram-positive bacteria to vancomycin, ciprofloxacin and gentamicin was low, and the resistance to penicillin, cefuroxime, ampicillin, cefotaxime, erythromycin and levofloxacin was high. The main Gram-negative bacteria had low resistance to gentamicin, imipenem and penicillin, but high resistance to levofloxacin, cefotaxime, cefuroxime, ampicillin and vancomycin. The clinical data of oral mucositis patients with oral ulcer (severe) and without oral ulcer (mild) were compared, and it was found that there were statistically significant differences in poor oral hygiene, diabetes, sleep duration less than 8 hours per night between two groups (P<0.05). CONCLUSION Gram-positive bacteria is the main pathogen of oral mucositis in patients with malignant hematopathy after chemotherapy. It is sensitive to glycopeptide antibiotics and aminoglycosides antibiotics. Poor oral hygiene, diabetes and sleep duration less than 8 hours per night are risk factors for oral mucositis with oral ulcer (severe).
Humans ; Vancomycin/therapeutic use* ; Cefuroxime ; Levofloxacin ; Oral Ulcer/drug therapy* ; Drug Resistance, Bacterial ; Anti-Bacterial Agents/adverse effects* ; Ampicillin ; Penicillins ; Cefotaxime ; Gram-Positive Bacteria ; Gram-Negative Bacteria ; Gentamicins ; Stomatitis/drug therapy*

Microbial biofilm, a consortium of microbial cells protected by a self-produced polymer matrix, is considered as one main cause of current bacterial drug resistance. As a new type of antimicrobial agents, antimicrobial peptides provide a new strategy for the treatment of antibiotic resistant bacteria biofilm infections. Antimicrobial peptides have shown unique advantages in preventing microbial colonization of surfaces, killing bacteria in biofilms or disrupting the mature biofilm structure. This review systemically analyzes published data in the recent 30 years to summarize the possible anti-biofilm mechanisms of antimicrobial peptides. We hope that this review can provide reference for the treatment of infectious diseases by pathogenic microbial biofilm.
Anti-Bacterial Agents ; pharmacology ; Antimicrobial Cationic Peptides ; pharmacology ; Bacteria ; drug effects ; Biofilms ; drug effects ; Drug Resistance, Bacterial ; drug effects ; Microbial Sensitivity Tests ; Research ; trends

Objective: This study aimed to evaluate the genetic diversity, virulence, and antimicrobial resistance of isolates from clinical patients, tap water systems, and food. Methods: Ninety isolates were obtained from Ma'anshan, Anhui province, China, and subjected to multi-locus sequence typing (MLST) with six housekeeping genes. Their taxonomy was investigated using concatenated sequences, while their resistance to 12 antibiotics was evaluated. Ten putative virulence factors and several resistance genes were identified by PCR and sequencing. Results: The 90 isolates were divided into 84 sequence types, 80 of which were novel, indicating high genetic diversity. The isolates were classified into eight different species. PCR assays identified virulence genes in the isolates, with the enterotoxin and hemolysin genes , , , and found in 47 (52.2%), 13 (14.4%), 22 (24.4%), and 12 (13.3%) of the isolates, respectively. The majority of the isolates (≥ 90%) were susceptible to aztreonam, imipenem, cefepime, chloramphenicol, gentamicin, tetracycline, and ciprofloxacin. However, several resistance genes were detected in the isolates, as well as a new variant. Conclusions Sequence type, virulence properties, and antibiotic resistance vary in isolates from clinical patients, tap water systems, and food.
Aeromonas ; drug effects ; genetics ; isolation & purification ; pathogenicity ; Anti-Bacterial Agents ; pharmacology ; China ; Drinking Water ; microbiology ; Drug Resistance, Bacterial ; Food Microbiology ; Genetic Variation ; Gram-Negative Bacterial Infections ; microbiology ; Species Specificity ; Virulence

OBJECTIVE: To study the distribution and drug resistance of pathogens causing periprosthetic infections after hip and knee arthroplasty, and to formulate prevention and treatment strategies for drug-resistant bacteria. METHODS: The data of 146 cases of periprosthetic infection after primary hip and knee arthroplasty from 2010 to 2015 were collected, including 111 cases of periprosthetic infection after hip arthroplasty and 35 cases of periprosthetic infection after knee arthroplasty. The culture positive rate, pathogenic bacteria composition and drug resistance rate were counted over the years, and the change trend of pathogen distribution and drug resistance was analyzed. RESULTS: One hundredand eight strains of pathogenic bacteria were detected in 146 cases, and the positive rate of culture was 73.97%. Gram positive bacteria accounted for 55.48%, Staphylococcus epidermidis and Staphylococcus aureus accounted for 25.34% and 15.07% respectively. Gram negative bacteria accounted for 13.01%, including Enterobacter cloacae, Pseudomonas aeruginosa and Escherichia coli. There were 4 cases of Mycobacterium tuberculosis infection and mixed infection. The results of culture over the years showed that the constituent ratio of Gram positive bacteria had an increasing trend, fluctuating from 39.13% to 76.47%. The results of drug sensitivity showed that the pathogens were highly resistant to β-lactams, quinolones, clindamycin and gentamicin, and the drug resistance rate was increasing, but it was still sensitive to rifampicin, nitrofurantoin, tigecycline, linezolid and vancomycin. CONCLUSION Gram positive bacteria are the main pathogens of periprosthetic infection, and the proportion is increasing gradually.The pathogens have high resistance to many kinds of antibiotics, and the resistance rate is still increasing. To strengthen the monitoring of the distribution and drug resistance of pathogenic bacteria is helpful to grasp its change trend and formulate targeted prevention and control strategies.
Anti-Bacterial Agents/therapeutic use* ; Arthroplasty, Replacement, Knee/adverse effects* ; Drug Resistance ; Drug Resistance, Bacterial ; Gram-Positive Bacteria ; Microbial Sensitivity Tests ; Retrospective Studies

Cholera is a secretory diarrhoeal disease caused by infection with Vibrio cholerae, primarily the V. cholerae O1 El Tor biotype. There are approximately 2.9 million cases in 69 endemic countries annually, resulting in 95 000 deaths. Cholera is associated with poor infrastructure and lack of access to sanitation and clean drinking water. The current cholera epidemic in Yemen, linked to spread of V. cholerae O1 (Ogawa serotype), is associated with the ongoing war. This has devastated infrastructure and health services. The World Health Organization had estimated that 172 286 suspected cases arose between 27th April and 19th June 2017, including 1170 deaths. While there are three oral cholera vaccines prequalified by the World Health Organization, there are issues surrounding vaccination campaigns in conflict situations, exacerbated by external factors such as a global vaccine shortage. Major movements of people complicates surveillance and administration of double doses of vaccines. Cholera therapy mainly depends on rehydration, with use of antibiotics in more severe infections. Concerns have arisen about the rise of antibiotic resistance in cholera, due to mobile genetic elements. In this review, we give an overview of cholera epidemiology, virulence, antibiotic resistance, therapy and vaccines, in the light of the ongoing epidemic in Yemen.
Anti-Bacterial Agents ; therapeutic use ; Cholera ; drug therapy ; prevention & control ; Cholera Vaccines ; therapeutic use ; DNA, Bacterial ; genetics ; Disease Outbreaks ; Drug Resistance, Multiple, Bacterial ; Humans ; Microbial Sensitivity Tests ; Polymerase Chain Reaction ; Vibrio cholerae ; drug effects ; isolation & purification ; Virulence Factors ; genetics ; Yemen

As one of the most common pathogens in aquatic animals, Aeromonas hydrophila exhibits a wide range of pathogenicity. Due to factors like unreasonable use of antibiotics and horizontal gene transfer mediated by plasmids, many resistant strains of Aeromonas hydrophila were isolated from ready-to-eat seafood products in retail markets, supermarkets and restaurants. These strains carry many resistance genes. Therefore, it is essential to explore the key control points, and seek for prevention and control strategies so as to effectively alleviate antibiotic resistance. We review here the prevalence of drug resistance of Aeromonas hydrophila in China, and its main infection and resistance mechanisms, and the main means and strategies for reducing and preventing drug resistance. We also address further research directions and focus on drug resistance in Aeromonas hydrophila of the aquatic product.
Aeromonas hydrophila ; drug effects ; Animals ; Anti-Bacterial Agents ; pharmacology ; China ; epidemiology ; Drug Resistance, Bacterial ; Fish Diseases ; epidemiology ; microbiology ; Fisheries ; Fishes ; Gram-Negative Bacterial Infections ; epidemiology ; microbiology ; Research

Despite the documented antibiotic-induced disruption of the gut microbiota, the impact of antibiotic intake on strain-level dynamics, evolution of resistance genes, and factors influencing resistance dissemination potential remains poorly understood. To address this gap we analyzed public metagenomic datasets from 24 antibiotic treated subjects and controls, combined with an in-depth prospective functional study with two subjects investigating the bacterial community dynamics based on cultivation-dependent and independent methods. We observed that short-term antibiotic treatment shifted and diversified the resistome composition, increased the average copy number of antibiotic resistance genes, and altered the dominant strain genotypes in an individual-specific manner. More than 30% of the resistance genes underwent strong differentiation at the single nucleotide level during antibiotic treatment. We found that the increased potential for horizontal gene transfer, due to antibiotic administration, was ∼3-fold stronger in the differentiated resistance genes than the non-differentiated ones. This study highlights how antibiotic treatment has individualized impacts on the resistome and strain level composition, and drives the adaptive evolution of the gut microbiota.
Adult ; Anti-Bacterial Agents ; pharmacology ; Bacteria ; genetics ; isolation & purification ; Drug Resistance, Bacterial ; genetics ; Female ; Gastrointestinal Microbiome ; drug effects ; Humans ; Metagenomics ; Prospective Studies

Rifamycins, a group of bacterial RNA polymerase inhibitors, are the firstline antimicrobial drugs to treat tuberculosis. In light of the emergence of rifamycinresistant bacteria, development of new RNA polymerase inhibitors that kill rifamycinresistant bacteria with high bioavailability is urgent. Structural analysis of bacterial RNA polymerase in complex with inhibitors by crystallography and cryo-EM indicates that RNA polymerase inhibitors function through five distinct molecular mechanisms:inhibition of the extension of short RNA; competition with substrates; inhibition of the conformational change of the'bridge helix'; inhibition of clamp opening;inhibition of clamp closure. This article reviews the research progress of these five groups of RNA polymerase inhibitors to provide references for the modification of existing RNA polymerase inhibitors and the discovery of new RNA polymerase inhibitors.
Antitubercular Agents ; therapeutic use ; Bacteria ; drug effects ; enzymology ; DNA-Directed RNA Polymerases ; metabolism ; Drug Discovery ; trends ; Drug Resistance, Bacterial ; Enzyme Activation ; drug effects ; Enzyme Inhibitors ; pharmacology ; Humans ; RNA, Bacterial ; Tuberculosis ; drug therapy ; enzymology

Most of the intra-abdominal infections are benign and critical diseases caused by trauma, surgery and gastrointestinal diseases, which require the attention of surgeons. The increase of drug resistance of pathogens is a common clinical problem. The intra-abdominal infection caused by multidrug-resistant bacteria is a huge challenge faced by clinicians, and is mainly found in hospital-acquired abdominal infections, of which gram-negative bacteria are the most common. This paper firstly summarizes the common types, early diagnosis and risk factors of multidrug-resistant bacteria according to the literature, and then describes the treatment strategy of intra-abdominal infection caused by multidrug-resistant bacteria from four aspects: anti-infective medication, infection source control, resuscitation and organ support, and nutritional support treatment. In addition, we should promote gastrointestinal function recovery through nutritional support treatment and prevent intestinal source infection, on the basis of understanding the risk factors of multidrug-resistant infection, rational use of anti-infective medication and infection source control measures. At the same time, proper organ function support can help to improve the success rate in the treatment of multidrug-resistant intra-abdominal infection.
Abdominal Cavity ; Anti-Bacterial Agents ; Bacteria ; drug effects ; Bacterial Infections ; microbiology ; prevention & control ; therapy ; Cross Infection ; Drug Resistance, Bacterial ; Drug Resistance, Multiple ; Humans ; Intraabdominal Infections

OBJECTIVE: To investigate the phylogenetics and prevalence of bloodstream infections with ST131, the antimicrobial resistance profiles of the pathogens, and the clinical features. METHODS: Non-duplicate isolates were collected from 144 patients with bloodstream infections in our hospital between January and December, 2016.The phylogenetic groups of the isolates were analyzed using multiplex PCR, and O serotyping of ST131 strains was performed by allele-specific PCR.The clinical characteristics of the 144 patients were analyzed to define the differences in the clinical features between patients with ST131 infection and those with non-ST131 infection.Antibiotic susceptibility of the isolates was determined using the Vitek 2 compact system. RESULTS: The phylogenetic group analysis showed a domination by group B2 (41.0%[59/144]), followed by group F, group B1 and group E, which accounted for 16.7%(24/144), 13.9%(20/144), and 13.2% (19/144), respectively.Nine strains (6.3%) of were identified to be ST131 strains, among which 8 were O25b-B2-ST131 strains and 1 was O16-B2-ST131 strain.Of the 9 cases of ST131 infection, 7(77.8%) were found to occur in a nosocomial setting.The demographic characteristics and clinical features of the ST131-infected patients were similar to those of non-ST131-infected patients.ST131 strains were sensitive to piperacillin/tazobactam, imipenem, ertapenem, and amikacin, but showed high resistance rates to cefazolin, ceftriaxone, ciprofloxacin, levofloxacin, gentamicin, and trimethoprim/ sulfamethoxazole (all over 50%).The positivity rate of ESBLs in the ST131 strains was 77.8%, and the multidrug resistance rate reached 88.9%, which was higher than that of non-ST131 isolates, but the difference was not statistically significant. CONCLUSIONS The most common phylogenetic groups of isolates from patients with bloodstream infections are group B2 and F, and the positivity rate of ST131 is low.We for the first time detected O16-ST131 in patients with blood-borne infections in China.The clinical features of ST131-infected patients are similar to those of non-ST131-infected patients.The positivity rate of ESBLs and the multidrug resistance rate are high in ST131 strains, which may raise concerns in the future.
Anti-Bacterial Agents ; therapeutic use ; Bacteremia ; drug therapy ; epidemiology ; microbiology ; China ; Drug Resistance, Bacterial ; Escherichia coli ; classification ; drug effects ; genetics ; Escherichia coli Infections ; drug therapy ; epidemiology ; microbiology ; Genotype ; Humans ; Microbial Sensitivity Tests ; Molecular Epidemiology ; Phylogeny ; Species Specificity