Infection and Drug Resistance最新文献

Purpose: New economic, rapid, and efficient diagnostic methods are desirable for the control of tuberculosis. This study aimed to evaluate the performance of a dual-gene qPCR melting curve assay (DGPMC) in detecting tuberculosis among patients with suspected pulmonary tuberculosis.

Patients and methods: The DGPMC assay based on rpoB and IS6110 gene sequences has been established for detection of Mycobacterium tuberculosis. A prospective study was conducted among adult patients with suspected pulmonary tuberculosis from June 2021 to September 2023 at Shanghai Pulmonary Hospital, China. All patients received symptom assessment, high-resolution chest CT scan, and bronchoscopy. Bronchoalveolar lavage fluid was collected for mycobacterial culture and acid-fast staining, GeneXpert MTB/RIF, and DGPMC assay. The diagnostic performance of DGPMC assay was evaluated against the composite reference standard.

Results: Overall, 240 patients were included in this trial, including 80 (33.3%) asymptomatic patients. Clinical diagnosis of tuberculosis was confirmed in 191 (79.6%) patients and 49 (20.4%) patients were confirmed without tuberculosis. The overall sensitivity of the DGPMC assay was 55.0% (95% CI: 47.6-62.1%), and the corresponding specificity was 85.7% (95% CI: 72.1-93.6%) in the diagnosis of tuberculosis. The sensitivity of DGPMC assay was higher than that of GeneXpert test (55.0% vs 47.1%, P = 0.038). The Youden index and weighted Youden index of the DGPMC assay were 40.7% and 28.4%, respectively. Subgroup analyses demonstrated that the sensitivity was 32.4% (95% CI: 22.3-44.4%) in the individuals with negative results for both culture and GeneXpert test. The DGPMC assay performed significantly better than the melting curves based on rpoB gene or IS6110 gene alone (P = 0.0000; P = 0.0020).

Conclusion: The DGPMC assay is an alternative tool favorable for the detection of tuberculosis in patients with suspected pulmonary tuberculosis, especially in the patients with low bacterial load.

Purpose: This study aimed to investigate and elucidate the clinical characteristics, immune status, infection types and patterns, treatment responses, and disease progression in patients with positive anti-interferon-gamma (IFN-γ) autoantibodies in combination with Mycobacterium infections.

Patients and methods: We conducted a retrospective analysis of clinical data from patients with positive anti-IFN-γ autoantibodies and concurrent Mycobacterial infections, including Mycobacterial infections (MTB) and non-tuberculous mycobacteria (NTM). The study included cases treated at the Fourth People's Hospital of Nanning, Guangxi, from 2018 to 2023. Data collected comprised symptoms, clinical signs, laboratory test results, imaging findings, and other relevant clinical information. Patients were also followed up to evaluate treatment responses and long-term therapeutic outcomes.

Results: A total of 30 patients with MTB and NTM infections were analyzed. The majority presented with common symptoms, such as cough, sputum production, weight loss, extrapulmonary tuberculosis (TB), and a range of opportunistic infections. Laboratory and imaging studies revealed complex infection patterns and various pathological changes. Treatment primarily involved targeted anti-infective therapy combined with immunosupportive measures. However, frequent treatment relapses and side effects were observed, resulting in two deaths.

Conclusion: Immune deficiency associated with positive anti-IFN-γ autoantibodies resembles the immunosuppression seen in advanced stages of human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS), rendering patients highly susceptible to opportunistic infections. These infections were predominantly caused by NTM, followed by MTB and Talaromyces marneffei (TM). This represents a novel immune deficiency syndrome that predisposes patients to a spectrum of opportunistic infections.

Purpose of the study: This study investigated post-coronavirus disease 2019 (COVID-19) sequelae among a sample of the Chinese population, and determined the statistical significance of correlations between age, sex, number of COVID-19 vaccinations, number of SARS-CoV-2 infections, development of pneumonia, use of specific drugs (namatevir/ritonavir, azvudine, molnupiravir), chronic underlying diseases, and post-COVID-19 sequelae.

Methods: Data from 869 patients, who visited the Emergency Department of Beijing Shijitan Hospital (Beijing, China) between December 7, 2022 to January 31, 2024, were collected. The criteria for admission: Age ≥ 14 years old, and diagnosed with ≥ 1 positive result on nucleic acid or antigen tests. Retrospectively analyzed the main manifestations of sequelae, statistical analysis of the relationship between age; sex; underlying diseases; number of COVID-19 vaccinations received; use of specific antiviral drugs for COVID-19 and prognosis, and statistical analyses, including logistic regression, were performed. Differences with P < 0.05 were considered to be statistically significant. Before entering the model, variables are screened using stepwise regression to ensure that the selected variables are the main ones related to the research question, thereby controlling for confounding factors. SPSS version 27 (IBM Corp. Armonk, NY, USA) was used for statistical analysis. In this study, the duration of sequelae ranged from 2 to 13 months.

Results and conclusions: This study retrospectively analyzed 869 patients (415 male, 454 female), with an average age of 61.52 ± 23.09 years. There were 401 patients without underlying conditions and 468 patients with one or more underlying conditions. Regarding COVID-19 vaccination status, 320 patients were unvaccinated, while 576 patients received at least one dose of the COVID-19 vaccine. Additionally, 514 patients received antiviral medication, while 355 did not receive antiviral treatment. The primary manifestations of post-COVID-19 included shortness of breath, dizziness and weakness, chronic pneumonia, asthma, and reduced sense of smell. Individuals ≥ 70 years of age were more prone to COVID-19 pneumonia. Patients with underlying disease(s) exhibited statistically higher mortality rates after diagnosis of COVID-19. Vaccination against COVID-19 and the use of specific drugs had a statistically significant effect on mortality and the occurrence of post-COVID-19 sequelae. There was no statistically significant difference in COVID-19 infection rates between males and females, although males were more prone to COVID-19 pneumonia. Young women with COVID-19 often experienced no sequelae, and elderly males exhibited a high mortality rate.

Purpose: This study evaluates and compares the eradication rates of Helicobacter pylori (H. pylori) achieved through susceptibility-guided therapy (SGT) based on resistance genotyping and empirical therapy (ET).

Patients and methods: A retrospective study was conducted at Beijing Chaoyang Hospital (2021-2023) on patients with H. pylori infection receiving initial eradication therapy. Resistance genotypes for clarithromycin and levofloxacin were identified using fluorescent PCR of gastric biopsy samples. Patients underwent a 14-day bismuth-containing quadruple therapy (BQT) and were evaluated via the C13 urea breath test (UBT). Based on genotyping or clinical judgment, 550 patients were assigned to SGT (n = 125) or ET (n = 425). The SGT group received personalized treatment based on genotype testing results, avoiding the use of antibiotics to which the bacteria were resistant. The ET group received the standard bismuth-containing quadruple therapy (BQT). Additionally, 29 ET patients underwent follow-up genotypic testing and eradication rates were analyzed retrospectively.

Results: SGT achieved higher eradication rates than ET (ITT: 94.4% vs 86.1%, P = 0.012; PP: 95.2% vs 87.6%, P = 0.016). In levofloxacin-resistant strains, SGT showed significantly higher eradication rates in the PP analysis (95.7% vs 50.0%, P = 0.049).

Conclusion: SGT exhibited remarkably superior eradication rates, notably in levofloxacin-resistant strains, proposing a compelling alternative for the treatment of H. pylori, particularly in instances of antimicrobial resistance.

The toxin-antitoxin (TA) system is widespread in prokaryotes and archaea, comprising toxins and antitoxins that counterbalance each other. Based on the nature and mode of action of antitoxins, they are classified into eight groups (type I to VIII). Both the toxins and the antitoxins are proteins in type II TA systems, and the antitoxin gene is usually upstream of the toxin gene. Both genes are organized in an operon and expression of which is regulated at the transcriptional level by the antitoxin-toxin complex, which binds the operon DNA through the DNA-binding domain of the antitoxin. The TA system plays a crucial role in various cellular processes, such as programmed cell death, cell growth, persistence, and virulence. Currently, Type II TA systems have been used as a target for developing new antibacterial agents for treatment. Therefore, the focus of this review is to understand the unique response of Type II TA in Escherichia coli to stress and its contribution to the maintenance of resistant strains. Here, we review the Type II TA system in E. coli and describe their regulatory mechanisms and biological functions. Understanding how TA promotes phenotypic heterogeneity and pathogenesis mechanisms may help to develop new treatments for infections caused by pathogens rationally.

Objective: This study investigated the distribution and antibiotic resistance profiles of common bacteria isolated from clinical specimens at a hospital's microbiology laboratory between 2020 and 2022.

Methods: A retrospective analysis was conducted on microbial culture results from clinical specimens collected over three years, including sample types, departmental distribution, pathogen species, and resistance profiles.

Results: A total of 13,048 unique pathogenic strains were isolated, predominantly from respiratory and urine specimens. Secretion specimens exhibited the highest positive detection rate (73.6%), while blood specimens showed a lower rate (9.7%). The five most frequently isolated pathogens were: Klebsiella pneumoniae (K. pneumoniae) (19.6%), Pseudomonas aeruginosa (P. aeruginosa) (14.7%), Escherichia coli (E. coli) (9.2%), Acinetobacter baumannii (A. baumannii) (8.0%), and Candida albicans (C. albicans) (7.0%). Gram-negative bacteria constituted 53.7% of all isolates (7009/13,048). A total of 7590 multidrug-resistant organisms (MDRO) were identified, corresponding to a detection rate of 21.3% (7590/35,613). The detection rates of carbapenem-resistant Enterobacteriaceae (CRE) increased annually: 7.2% (2020), 8.6% (2021), and 14.4% (2022).

Conclusion: The annual detection rate of CRE increased during the study period, while the rate of methicillin-resistant Staphylococcus aureus (MRSA) declined. Timely and effective interventions targeting pathogenic bacteria are essential for controlling and mitigating nosocomial infection risks.

Objective: In the real clinical world, both surgery and medication are used to treat pulmonary aspergillosis (PA), but the prognosis of different treatments is unclear. The purpose of this study was to investigate the diagnosis and treatment, follow-up results and prognostic factors of PA patients in the real world, so as to deepen our understanding of PA and improve the prognosis of PA patients.

Materials and methods: Eligible patients with pathologically diagnosed PA (n = 125) were retrospectively enrolled and followed up. Further comparisons and subgroup analyses were performed between patients receiving surgical and nonsurgical treatments. Univariate and multivariate logistic regression analyses were used to investigate the factors associated with treatment failure.

Results: A total of 125 patients with PA were included in the study. Of these, 49 (39.2%) received surgical treatment (25 of whom also received postoperative antifungal therapy), while 76 (60.8%) received antifungal therapy alone. The median age was 59 years (46.5-67 years). Compared with the nonsurgical group, the surgical group had lower inflammatory cell counts and less inflammatory response, and higher hemoglobin and albumin levels. Multivariate logistic regression analysis showed that white blood cell (WBC) levels >9.5×10⁹/L and C-reactive protein (CRP) levels >8 mg/L were independent predictors linked to treatment failure.

Conclusion: PA patients with severe inflammation and poor general health are usually treated with antifungal drugs only. Risk factors including elevated WBC levels and high CRP levels can help identify PA patients who may have a less favorable response to treatment at an early stage. It should be noted that increasing the dose and duration of antifungal therapy may improve patient prognosis.

Background: The prevalence of third-generation cephalosporin-resistant and extended-spectrum beta-lactamases (ESBL) producing Escherichia coli poses a significant global public health concern due to their resistance to multiple antibiotics; however, their prevalence and epidemiological patterns in China are not very well investigated.

Objective: This study aimed to investigate the molecular epidemiology, and antimicrobial susceptibility of ESBL-producing E. coli among clinical isolates in China.

Methods: Phenotypic ESBL-producing E. coli isolates were collected from in-patients at a non-tertiary hospital in Suzhou from 2018.06.01 -2019.11.30. All isolates were identified and analyzed by conventional microbiological methods, and antimicrobial susceptibility testing was determined. Genes associated with resistance to β-lactamases, fluoroquinolone, aminoglycosides, sulfonamides, sequence types (STs), and genetic relationship were characterized through whole-genome sequencing (WGS) data.

Results: Eighty-six isolates were collected and sequenced, and genomic analysis identified twenty-five different sequence types (STs). The most prevalent STs were ST131 (n=22, 25.6%), ST1193 (n=16, 18.6%), ST38 (n=9, 10.5%) and ST167 (n=6, 7.0%). blaCTX-M genotypes were the most dominant, comprising a variety of subtypes (eg, blaCTX-M-14, blaCTX-M-15, blaCTX-M-27, blaCTX-M-55) and blaTEM-type among ESBL-producing E. coli in our study. All cases of co-carriage of β-lactamase genes showed a strong link to amoxicillin/sulbactam resistance, while the co-carriage of blaCTX-M-15/TEM-1B or blaCTX-M-15/OXA-1 were strongly linked to resistance against cefepime, ceftazidime, and aztreonam. In addition, genes associated with resistance to fluoroquinolone, aminoglycosides, and sulfonamides were also detected.

Conclusion: Our findings highlighted the prevalence of globally circulating ESBL-producing E. coli clones, such as ST131 and ST1193, in Suzhou, China. These clones and sublineages are also resistant to quinolones. No predominant blaCTX-M subtypes were detected, while the coexistence of different ESBL types was strongly linked to resistance to amoxicillin/sulbactam, cefepime, ceftazidime, and aztreonam, suggesting the widespread circulation of diverse blaCTX-M genes within the Suzhou community. In clinical cases of ESBL resistance, carbapenem therapy is recommended as most (>90%) isolates were susceptible.

The increasing incidence of antibiotic resistance in Staphylococcus aureus (S. aureus) poses a substantial threat to global public health. In recent decades, the evolution of bacteria and the misuse of antibiotics have led to a progressive development in drug resistance of S. aureus, resulting in a worldwide rise in methicillin-resistant S. aureus (MRSA) infection rates. Understanding the molecular mechanisms underlying staphylococcal drug resistance, the treatments for staphylococcal infections, and the efficacy of nanomaterials in addressing multi-drug resistance is crucial. This review explores the resistance mechanisms, which include limiting drug uptake, target modification, drug inactivation through the production of degrading enzymes, and active efflux of drugs. It also examines the current therapeutic strategies, such as antibiotic combination therapy, phage therapy, monoclonal antibody therapy, and nanoparticle therapy, with a particular emphasis on the role of silver-based nanomaterials. Nanoparticles possess the ability to overcome multi-drug resistance, offering a novel avenue for the management of drug-resistant bacteria. The nanomaterials have demonstrated potent antibacterial activity against S. aureus through various mechanisms, including cell membrane disruption, generation of reactive oxygen species (ROS), and inhibition of essential cellular processes. It also highlights the need for further research to optimize nanoparticle design, enhance their antibacterial potency, and ensure their biocompatibility and biodegradability. The review ultimately concludes by emphasizing the importance of a multifaceted approach to treatment, including the development of new antibiotics, investment in stewardship programs to prevent antibiotic misuse, and the exploration of natural compounds and bacteriocins as potential antimicrobial agents.

Purpose: This study aimed to investigate the epidemiology and dissemination of mcr-positive Enterobacteriaceae in urban sewage in Yangzhou, China.

Methods: A total of 366 sewage samples were collected from the Yangzhou Wastewater Treatment Plant in Jiangsu Province. Colistin-resistant Enterobacteriaceae was identified through PCR targeting mcr-1 to mcr-10 genes. The isolates underwent antimicrobial susceptibility testing, and whole-genome sequencing was performed to analyze their genomic features. Additionally, conjugation experiments were conducted to assess the transferability of mcr-positive plasmids.

Results: Three mcr-positive Enterobacteriaceae isolates were identified, representing an isolation rate of 0.82%. These included one mcr-1-positive Escherichia coli (ST167) and two mcr-10-positive Klebsiella pneumoniae complex strains with novel sequence types ST6801 and ST6825. The mcr-1 gene was located on an IncI2 plasmid (pYZ22WS208_3) and successfully transferred to recipient strains. In contrast, the mcr-10 gene was carried on IncF plasmids (pYZ22WS067_1 and pYZ22WS223_1) but was not transferable in this study. Phylogenetic analysis revealed that the mcr-1-positive E. coli strain clustered within Clade II, alongside strains from various countries and sources. Phylogenomic analysis of mcr-10-positive isolates showed their sporadic distribution across 13 countries, with associations to diverse hosts and environments, indicating potential for widespread transmission.

Conclusion: This study demonstrates the presence of mcr-1 and mcr-10-positive Enterobacteriaceae in wastewater, emphasizing the importance of wastewater surveillance for tracking antibiotic resistance. The horizontal transfer of mcr-1 and potential spread of mcr-10 across various hosts underscore the need for ongoing monitoring and preventive measures.