Infection and Drug Resistance最新文献

Purpose: Septic shock is a severe complication in critically ill patients with COVID-19, often associated with poor prognosis. Predictive factors for septic shock remain undetermined. Our objective was to develop an early predictive model for septic shock in severe COVID-19 patients to assist emergency and critical care physicians in resource allocation and medical decision-making.

Patients and methods: The training cohort was sourced from the cases admitted to Northern Jiangsu People's Hospital between December 2022 and February 2023, while the validation cohort was retrieved from the MIMIC-IV dataset. The Least Absolute Shrinkage and Selection Operator (LASSO) analysis was used to screen for predictors. A multivariate logistic regression was employed to build the predictive model, which was then represented as a nomogram. The performance of the nomogram was evaluated using the Receiver Operating Characteristic (ROC) curve, calibration plot, and Decision Curve Analysis (DCA). External validation was conducted by assessing the model's performance in the validation cohort.

Results: A collective of 274 patients and 75 patients were respectively enrolled as the training cohort and the validation cohort in this study. The predictors included in the nomogram were albumin, mean arterial pressure, lactate, and the Sequential Organ Failure Assessment (SOFA) score. The area under the ROC curve (AUC) for the modeling set was 0.800 (95% CI 0.741-0.858), and for the validation set, it was 0.775 (95% CI 0.651-0.899). Additionally, the calibration curve indicated a correlation between predicted and observed outcomes, and DCA highlighted the clinical utility of the nomogram.

Conclusion: We developed and validated a diagnostic nomogram model for septic shock in critically ill COVID-19 patients, incorporating four parameters: SOFA score, albumin, mean arterial pressure, and lactate. This model demonstrates significant potential in predicting septic shock among critically ill COVID-19 patients.

We present the case of an 18-year-old previously healthy female diagnosed with Mycoplasma pneumoniae pneumonia who developed marked elevation in D-dimer and fibrinogen degradation products, along with de novo positivity for both IgG and IgM anticardiolipin antibodies, shortly after initiating intravenous omadacycline therapy. These findings occurred in the absence of known antiphospholipid syndrome or other autoimmune conditions. The patient also experienced gastrointestinal symptoms and skin rashes. After discontinuation of omadacycline and supportive care, her condition improved. This case highlights the temporal association between omadacycline administration and the emergence of immune-coagulative dysregulation. Given that Mycoplasma pneumoniae infection itself can cause similar extrapulmonary manifestations, a definitive causal link cannot be established. This case suggests a probable, though rare, association between omadacycline and immune-coagulative dysregulation. Clinicians should be vigilant for such signals, particularly in patients developing early cutaneous or gastrointestinal symptoms during therapy.

Background: Chikungunya fever has emerged as a significant public health concern in tropical and subtropical regions worldwide. Understanding the epidemiological patterns and clinical features of chikungunya virus infection is crucial for developing effective disease surveillance and management strategies.

Methods: We conducted a retrospective analysis of 311 laboratory-confirmed chikungunya fever cases presenting to a tertiary hospital in Foshan, Guangdong Province, China, from June to September 2025.

Results: The study population had a median age of 32.35 years (interquartile range: 10-53 years), with females comprising 56.3%. Fever occurred in 85.9% of patients, with 49.2% experiencing moderate to high-grade fever. Joint symptoms were present in 76.5% of patients, with 48.6% developing moderate to severe arthralgia. Rash was a significant clinical manifestation with an incidence of 73%, of which 44.1% of patients presented with severe rash. Laboratory abnormalities included leukopenia (6.4%), lymphopenia (64.6%), and elevated C-reactive protein (66.2%). Multivariate analysis identified rash presence, joint symptoms, and younger age as factors significantly associated with moderate-severe disease presentations. However, as rash and joint symptom severity were incorporated into the severity scoring system, these associations should be interpreted as descriptive characterization rather than independent prediction.

Conclusion: This study characterizes the clinical features of acute chikungunya fever, with age-related severity differences and specific clinical and laboratory markers associated with disease severity. Rash emerges as a significant clinical manifestation associated with disease severity, highlighting its value in clinical assessment of chikungunya fever. These findings support the development of risk stratification tools and evidence-based management protocols for chikungunya fever patients.

Purpose: Carbapenem-resistant Enterobacteriaceae (CRE) colonization poses a major threat to the success of allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, evidence on its long-term impact and the role of decolonization strategies remains limited.

Methods: This study included 240 allo-HSCT recipients prospectively screened for pre-transplant rectal CRE colonization (colonized n=80; non-colonized n=160; 1:2 matching). Inverse probability of treatment weighting (IPTW) was applied to achieve covariate balance (standardized mean difference <0.10). Key outcomes included CRE bloodstream infection (BSI) incidence, hematopoietic engraftment time, graft-versus-host disease (GVHD) onset, and 3-year overall survival (OS), analyzed using Kaplan-Meier curves and Cox proportional hazards models. Strain and carbapenemase enzyme concordance between colonizing and infecting isolates were evaluated in BSI cases.

Results: CRE BSI occurred almost exclusively in colonized patients (26.6%, 21/79), with 81.0% strain concordance (predominantly Escherichia coli and Klebsiella pneumoniae) and 77.8% enzyme profile concordance (mainly metallo-β-lactamase/NDM) between pre-transplant colonizing and post-transplant infecting isolates. An 81.0% concordance rate was observed between CRE strain types isolated from perianal colonization samples and those from bloodstream infections. BSI-attributable 100-day mortality was 34.8% (8/23). Colonized patients exhibited delayed engraftment (neutrophils: 14 vs 13 days, P=0.044; platelets: 15 vs 14 days, P=0.014) and earlier chronic GVHD onset (150 vs 235 days, P=0.004), with comparable GVHD incidence. Both unweighted and IPTW-adjusted 3-year OS were markedly lower in colonized patients (62.5%/58% vs 85.0%/83%; HR 3.49, 95% CI 1.91-6.38, P<0.001).

Conclusion: Pre-transplant CRE colonization is strongly associated with poorer allo-HSCT outcomes, including increased CRE BSI incidence and 100-day mortality, delayed engraftment, accelerated cGVHD onset, and approximately threefold higher 3-year mortality risk. These findings position CRE colonization as a potentially modifiable driver of both early and long-term morbidity, highlighting the critical need for routine screening and targeted decolonization strategies to improve survival in this high-risk population.

Background: Anti-interferon-γ autoantibodies (AIGAs) immunodeficiency syndrome is a rare acquired disorder characterized by impaired IFN-γ signaling, predisposing patients to severe intracellular infections. While disseminated non-tuberculous mycobacteria (NTM) and Talaromyces marneffei (TM) are well-documented pathogens, the clinical and immunological features of Salmonella coinfection remain poorly characterized.

Methods: This retrospective study analyzed 12 HIV-negative patients with AIGAs-positive status and confirmed Salmonella infection at the First Affiliated Hospital of Guangxi Medical University, China (2021-2024). Data included demographics, clinical manifestations, laboratory findings, co-infections, treatment, and outcomes. AIGAs were detected via ELISA and Western blot, with neutralizing activity confirmed by STAT1 phosphorylation inhibition.

Results: The cohort was predominantly composed of middle-aged males (83.3%, mean age 55.75 ±8.06 years). The most common symptoms were fever, fatigue and cough (each 91.7%), followed by poor appetite (83.3%), systemic symptoms (chills, weight loss; 58.3%) and dyspnea (58.3%). Bone or joint pain occurred in 41.7% and gastrointestinal complaints (abdominal pain, diarrhea or distension) in 25%. Five patients (41.7%) developed septic shock, three requiring vasopressors and two mechanical ventilations. All had high AIGAs titres (1:2500) and hyper-inflammation (median WBC17.3×10⁹/L, CRP138.1mg/dL, PCT1.28ng/mL). Bacteraemia was present in 91.7% and mortality was 16.7% (2/12). Polymicrobial co-infection was universal; notably cytomegalovirus (50%) and TM (25%). Immunological profiling showed hyperglobulinaemia (IgG23.5±10.6g/L) and elevated IgE (257.5[79.7-598.2]IU/mL). Despite broad-spectrum antibiotics (83.3% survival), both fatalities occurred in patients who had not undergone NGS-based diagnosis.

Conclusion: This study is the first to define AIGAs-associated Salmonella infection as a distinct clinical syndrome, characterized by severe bacteremia, paradoxical hyperinflammation, universal polymicrobial coinfections, and immune dysregulation. Our findings underscore the critical importance of comprehensive pathogen detection, particularly via NGS, for timely diagnosis and improved patient outcomes.

Purpose: This study aimed to explore the resistance mechanisms and molecular characteristics of linezolid-non-susceptible Enterococcus faecium isolates (LNSEFM) from a tertiary hospital in Beijing, China, focusing on novel findings with significant clinical and epidemiological implications.

Patients and methods: LNSEFM strains isolated from clinical specimens between January 2011 and December 2023 were collected and screened for resistance genes, including rplC, rplD, rplV, 23s rRNA, optrA, poxtA, and cfr using polymerase chain reaction (PCR) and DNA sequencing. Molecular epidemiological analysis was performed using multi-locus sequence typing (MLST). Isolates carrying optrA and those harboring poxtA were subjected to whole-genome sequencing (WGS).

Results: Among 2384 clinical E. faecium isolates, 19 (0.80%) were linezolid-non-susceptible (MIC 4-32 mg/L). Among these, two vancomycin-resistant Enterococcus (VRE) strains exhibited an intermediate susceptibility to linezolid. Two distinct optrA variants (designated as KLDK and KLDP) were detected in separate LNSEFM isolates. The KLDK-positive isolate was found to co-harbor the vanM gene cluster despite maintaining vancomycin susceptibility. Additionally, one linezolid-resistant isolate carried a G2576T mutation in the 23S rRNA gene, whereas the other harbored the poxtA gene. MLST revealed 13 sequence types (STs) among the isolates, including a novel type ST2709.

Conclusion: This study identified key notable findings in LNSEFM: identification of linezolid intermediate VRE in China, clinical detection of the optrA KLDK variant in enterococci, optrA-vanM co-presence in vancomycin-susceptible E. faecium, and a novel sequence type (ST2709). These findings enrich our understanding of the molecular epidemiology of LNSEFM and provide critical insights into clinical antimicrobial management and infection control.

Purpose: This study aimed to evaluate the diagnostic accuracy and clinical applicability of metagenomic next-generation sequencing (mNGS) in pulmonary infections by comparing it with traditional culture methods in a Traditional Chinese Medicine (TCM) hospital setting.

Methods: This retrospective cohort study enrolled 67 consecutively admitted patients with radiologically and clinically confirmed pulmonary infections from the Department of Respiratory Infectious Diseases at Xinchang Hospital of Traditional Chinese Medicine between December 2022 and September 2024. Clinical specimens included blood, bronchoalveolar lavage fluid (BALF), sputum, hydrothorax and cerebrospinal fluid (CSF). mNGS and conventional culture were performed to compare detection rates and microbial community profiles.

Results: Among 67 cases, mNGS identified pathogens in 89.55% (60/67), compared to 20.90% (14/67) by traditional culture. Of 14 dual-positive cases, only 1 (1/14, 7.14%) showed complete concordance, while most exhibited discordance or partial genus-level overlap. mNGS further detected viral co-infections in 44.78% (30/67) and identified fastidious/non-culturable pathogens such as enterovirus, human herpesvirus type 1, and Mycobacterium tuberculosis. Patients with chronic diseases were more susceptible to EB virus infections.

Conclusion: mNGS significantly enhances pathogen detection in pulmonary infections, supports targeted antimicrobial therapy, and holds potential for contributing to clinical outcomes and reducing antibiotic resistance.

Background: Chlamydia abortus is a zoonotic pathogen that commonly causes abortion, pelvic inflammatory disease, or septicemia during pregnancy in humans. It can occasionally lead to pneumonia.

Case presentation: We report a 35-year-old male with pneumonia complicated by psychiatric symptoms and pneumomediastinum. Initial treatment with cefotaxime and piperacillin-tazobactam failed. On admission, chest CT revealed bilateral pulmonary inflammation, pneumomediastinum, and cervical subcutaneous emphysema. Bronchoalveolar lavage fluid underwent Targeted Next-Generation Sequencing, identifying Chlamydia abortus. Treatment with doxycycline and moxifloxacin led to resolution of fever, psychiatric symptoms, and pulmonary lesions. The patient continued oral doxycycline post-discharge, and follow-up CT showed near-complete recovery.

Conclusion: Chlamydia abortus infection can cause pneumonia with psychiatric symptoms, pneumomediastinum, and cervical emphysema-complications not previously reported. Targeted Next-Generation Sequencing (Targeted NGS) plays a crucial role in the early and precise detection of Chlamydia abortus, improving diagnostic accuracy and treatment timeliness. Doxycycline is effective in the treatment of Chlamydia abortus infection and contributed to the patient's recovery.

Background: Scedosporium aurantiacum is a rare opportunistic pathogen distributed worldwide. S. aurantiacum can cause invasive infections in both immunocompromised and immunocompetent individuals following exposure to contaminated environments. The risk associated with wastewater exposure is an important public health concern. Owing to its multi-drug resistance, the treatment of S. aurantiacum infection is very challenging.

Case presentation: We report a case of a 44-year-old Chinese male with disseminated infection and endocarditis caused by S. aurantiacum after falling into a nearly dry wastewater pool. S. aurantiacum isolated from blood cultures was identified using nanopore sequencing technology of internal transcribed spacer 1 (ITS1) and matrix-assisted laser desorption ionization/time-of-flight mass spectrometry (MALDI-TOF MS). In vitro antifungal susceptibility testing indicated that voriconazole was the most active agent with a minimum inhibitory concentration (MIC) of 0.5 μg/mL. Despite receiving appropriate antifungal therapy, the patient died 12 days after fungal isolation because of uncontrolled infection and systemic organ failure.

Conclusion: This is the first reported clinical case of S. aurantiacum endocarditis in China. This case highlights that even in immunocompetent patients, S. aurantiacum infection should be considered. For clinicians, understanding a detailed history of the contaminated environments that the patient has been exposed to is crucial for early diagnosis. Nanopore sequencing offers a new option for identifying S. aurantiacum. Drug susceptibility testing is essential for determining the most appropriate antimycotic agent.

Streptococcus pneumoniae (S.pn) is the predominant bacterial pathogen affecting children under 5 years old. Its polysaccharide capsule is the primary virulence factor, enabling the bacteria to evade the immune system and defining the serotypes that current vaccines target. Recently, nonencapsulated Streptococcus pneumoniae (NESp) have emerged as significant causes of conjunctivitis, otitis media, and invasive diseases worldwide. This report provides the first integrated genomic and phenotypic analysis of two NESp strains identified in China. The NESp colonies are characterized by their rough texture and small size, and they exhibit a slower growth rate compared to other serotypes. Whole-genome sequencing has identified these NESps strains as belonging to the ST10236 type. Notably, these strains demonstrate multidrug resistance. In comparison to encapsulated strains, NESps possess fewer coding genes related to cell wall biogenesis and basal metabolism. However, they still retain crucial virulence genes including the pspK gene. Our findings highlight the clinical significance of NESps and emphasize the need for ongoing surveillance of these "capsule-free" clones in the post-PCV era.