Frontiers in Cellular and Infection Microbiology最新文献

Introduction: Multidrug-resistant Pseudomonas aeruginosa (MDRPA) is a life-threatening infection with limited treatment options. As a novel combination drug of cephalosporin and beta-lactamase inhibitor, ceftazidime/avibactam (CAZ/AVI) is not much used in clinical treatment of MDRPA infections. To fill in this knowledge gap, a single-center real-world study was conducted.

Methods: This single-center retrospective observational study included MDRPA-infected patients treated with CAZ/AVI or other antimicrobial agents between January 2019 and April 2021. Propensity score-matched and binary logistic regression analysis was used to compare the clinical and microbiological efficacy between CAZ/AVI and other antimicrobial agents.

Results: Totally 363 patients with MDRPA infection were enrolled, including 49 patients treated with CAZ/AVI and 314 patients treated with other antimicrobial agents. The CAZ/AVI group exhibited a reduced failure rate of clinical treatment (P = 0.012, OR = 0.381, 95% CI 0.180 - 0.807). Subgroup analysis showed single lung infection was a significant risk factor for clinical treatment failure in patients treated with other antimicrobial agents (P = 0.023, OR = 2.568, 95% CI 1.138 - 5.796). No significant discrepancy was observed in microbiological efficacy between the two groups (P = 0.159, OR = 0.587, 95% CI 0.280 - 1.232), or in clinical and microbiological efficacy between CAZ/AVI monotherapy and combination therapy.

Conclusions: CAZ/AVI demonstrates superior clinical efficacy against MDRPA in comparison to other antimicrobial agents. However, the administration of CAZ/AVI as part of combination therapy does not provide any clear benefits over monotherapy. Patients with single pulmonary infection caused by MDRPA show better clinical efficacy with CAZ/AVI. Further larger studies are needed to substantiate our findings.

Introduction: Extrapulmonary tuberculosis (EPTB) is characterized by atypical clinical symptoms, difficult diagnosis, and high mortality, so it is very important to know the prevalence and drug resistance (DR) status.

Methods: This study analyzed 427 isolates of EPTB from a Chinese hospital. Drug susceptibility testing for widely used anti-TB drugs was performed. All isolates were subjected to whole-genome sequencing (WGS) to explore the molecular characteristics of resistance and to perform phylogenetic analysis. Clinical characteristics and DR patterns associated with Mycobacterium tuberculosis (MTB) lineages were evaluated using chi-square analysis, and associations with DR-EPTB were assessed using multinomial logistic regression.

Results: The number of EPTB strains exhibited a general upward trend, and most EPTB cases in this study were accompanied by PTB. The predominant types were tuberculosis of urinary system (29.98%), tuberculous meningitis (23.65%), and lymph node tuberculosis (22.72%). Quadratic regression revealed a decline in urinary system cases and an increase in lymph node cases. Lineage 2 accounted for 83.60% of isolates and was significantly associated with isoniazid (INH) and streptomycin (STR) resistance. Overall resistance rates were 13.58% for INH and 7.73% for rifampicin (RIF). Male sex was associated with higher DR risk (aOR = 1.63, p = 0.046). Common resistance mutations included katG Ser315Thr, rpoB Ser450Leu, and gyrA mutations. The clustering rate was 19.67%, indicating limited recent transmission.

Discussion: The predominance of lineage 2 and high rates of anti-tuberculosis drug resistance indicate that EPTB remains a clinically and epidemiologically significant problem.

Purpose: Cryptococcal meningitis (CM) is a devastating central nervous system infection with substantial mortality, particularly when diagnosis is delayed. This study aims to evaluate the diagnostic performance of metagenomic next-generation sequencing (mNGS) for CM detection in comparison with conventional tests.

Methods: We enrolled 23 consecutive patients with suspected CM at a tertiary center. All patients met a composite reference standard (CRS) based on CSF cryptococcal antigen (CrAg), CSF/sterile-site culture for Cryptococcus, or CNS histopathology; mNGS was excluded from the CRS. Primary outcomes were CRS-based sensitivity (computed only among CRS-positive patients who underwent each assay) and turnaround times (TATs); pairwise agreement metrics (PPA/NPA) between mNGS and conventional assays were estimated in co-tested subsets.

Results: mNGS identified Cryptococcus in 18/23 (78.3%) cases and detected viral co-pathogens (EBV/CMV/HIV-1) in 5 patients. CRS-based sensitivities were: CrAg LFA (CSF) 83.3% (5/6), Alcian blue 72.7% (16/22), India ink 50.0% (3/6), and CSF culture 66.7% (8/12). Pairwise agreement favored mNGS against culture and CrAg (e.g., PPA 100% vs culture 8/8] and vs CSF CrAg [5/5]), with limited NPA where denominators were small. Median (IQR) TATs were 0.5 (0.5-0.5) days for CrAg LFA, 1 (0.5-1) day for India ink, 5 (3-8) days for first positive culture, and 2 (1-4) days for mNGS.

Conclusion: CSF mNGS complements CrAg, microscopy, and culture by increasing Cryptococcus detection and revealing mixed infections, with particular utility in atypical, pretreated, or complex hosts. Larger studies are warranted to validate clinical utility and define optimal integration with existing workflows.

Background: Probiotics are live microorganisms that may enhance or restore gut microbiota. They are often recommended during pregnancy and infancy for potential benefits, but evidence is inconclusive. This study aimed to investigate probiotic supplementation's effects on maternal and infant gut and milk microbiota and its link to nutrient intake during pregnancy.

Method: A total of 23 pregnant women were enrolled and divided into a probiotic group (n = 11) and a non-probiotic control group (n=12). Probiotic effects were evaluated through fecal and milk microbiota analysis via 16S rRNA gene sequencing. Nutrient intake data were collected to assess differences linked to probiotics. Key microbiota diversity and richness were analyzed using linear discriminant analysis effect size (LEfSe) and weighted gene co-expression network analysis (WGCNA) to explore associations with diet and sample characteristics. Predictive microbial pathway characteristics were identified using time series analysis, random forest algorithms, and logistic regression models.

Results: Nutrient intake did not significantly differ between groups, and overall microbial diversity and richness were stable. However, LEfSe revealed distinct genera in both maternal gut and milk microbiota linked to probiotic intake. WGCNA identified microbial modules correlated with specific nutrient patterns and sampling conditions. Predictive genus clusters associated with probiotics demonstrated robust classification performance, suggesting functional shifts in microbial communities with potential implications for immune programming in early life.

Conclusion: Probiotic supplementation during pregnancy may modulate key microbial taxa in maternal gut and milk, potentially influencing microbial recognition and immune signaling in the maternal-infant dyad. These findings highlight complex diet-microbiota-immune interactions within reproductive and lactational systems, offering insights into strategies for enhancing maternal and neonatal health resilience.

Invasive fungal infections (IFI) primarily occur in immunocompromised patients, particularly those in intensive care units (ICU). Due to the use of immunosuppressive agents, invasive therapeutic procedures, and advancements in diagnostic technologies, the detection rate of IFI has shown a significant upward trend. This review aims to explore epidemiological changes in the field of IFI, early detection techniques, and the application of artificial intelligence (AI) technologies. We conducted a literature review using PubMed data up to April 2025, focusing on studies related to IFI. Specifically, we focus on three aspects of IFI research: first, the epidemiology of IFI is undergoing significant changes, with Candida auris rapidly spreading across more than 40 countries worldwide, and rare fungal infections such as Mucor spp. and Fusarium spp. becoming increasingly prevalent; simultaneously, resistance to antifungal drugs among various pathogens continues to rise. Second, breakthroughs have been achieved in early detection technologies, including molecular detection techniques, biomarker testing, imaging technologies, and other emerging diagnostic methods, significantly enhancing the sensitivity and specificity of diagnosis. Thirdly, with the widespread application of AI technology, the development of clinical predictive models, the establishment of scoring rules, and the formulation of AI-based treatment decision-making tools are advancing the exploration of early diagnosis for IFI. In summary, as early diagnostic technologies for IFI continue to advance and AI algorithms are integrated into clinical practice, there is potential to improve the early diagnosis and treatment outcomes for critically ill patients with IFI.

Background: Carbapenem-resistant Gram-negative bacteria (CRGNB) pose a severe global health threat, yet comprehensive bibliometric analyses in this field remain limited. This systematic review employs a bibliometric methodology to identify research hotspots and emerging trends from 2020 to 2025.

Method: Literature published between January 1, 2020, and October 31, 2025, was retrieved from the Web of Science Core Collection (WoSCC), Scopus, and PubMed for bibliometric analysis. Analytical tools, including VOSviewer, CiteSpace, and the Bibliometrix package, were used to assess publications by number, country, institution, journal, author, and keywords.

Results: The bibliometric analysis revealed that global CRGNB research has experienced a fluctuating growth trend. China was the leading contributor, with 2,950 publications (25.5% of the total), and demonstrated significant collaboration with the USA and the UK. Major research clusters encompassed hypervirulent CRGNB strains (particularly carbapenem-resistant Klebsiella pneumoniae and Escherichia coli), resistance mechanisms (particularly carbapenemase-producing), antibiotic resistance, emerging therapeutic strategies (such as novel β-lactam/β-lactamase inhibitors, siderophore antibiotics, phage therapy, and antimicrobial peptides) and One Health perspectives (addressing environmental reservoirs). Thematic analysis identified evolving research priorities, including hypervirulent CRGNB strains, artificial intelligence, and early diagnosis and rapid screening of carbapenem resistance, exemplified by clustered regularly interspaced short palindromic repeats-based detection and artificial intelligence-driven matrix assisted laser desorption ionization-time of flight analysis. Randomized controlled trials indicated promising outcomes for several new antimicrobial agents, such as cefiderocol, sulbactam-durlobactam, and imipenem-relebactam. However, safety concerns, particularly in critically ill patients, remain a significant challenge.

Conclusion: CRGNB research is increasingly directed toward elucidating resistance mechanisms, improving diagnostic tools, and exploring non-antibiotic therapeutic options. Strengthening international collaboration and fostering multidisciplinary approaches are imperative to advance high-quality research and address this growing threat.

Introduction: Older women experience a significant decline in estrogen levels due to ovarian dysfunction, leading to a series of health issues such as lipid metabolism disorders, obesity, and increased risk of cardiovascular disease. Previous studies have shown that vitamin D deficiency can increase the risk of metabolic diseases.

Methods: This study used older female mice fed a high-fat diet as research subjects to investigate the effects of vitamin D on lipid metabolism abnormalities in older female mice and whether these effects are related to the regulation of the gut microbiota.

Results: Our results indicate that vitamin D supplementation reduces body weight, blood lipid levels, and mild inflammation in older female mice, improves hepatic steatosis and fibrosis, regulates the expression of fatty acid metabolism genes, and increases the expression of tight junction proteins in the gut. HepG2 fatty liver cells also validated these findings. Gut microbiota sequencing results showed that vitamin D supplementation significantly regulated the overall composition of the gut microbiota, reducing the abundance of microbiota associated with obesity and inflammation, increasing the abundance of beneficial bacteria, and reversing gut microbiota dysbiosis caused by a high-fat diet. Additionally, Spearman correlation analysis indicated that key microbial communities regulated by vitamin D were highly correlated with metabolic markers.

Conclusions: These results suggest that vitamin D could serve as a potential candidate drug for preventing lipid metabolism abnormalities caused by obesity in older female mice by regulating the gut microbiota.