Journal of Microbiology Immunology and Infection最新文献

Background: Viral infection plays an important role in driving activity of autoimmune diseases. Preceding SARS-CoV-2 infection has been observed to trigger disease flares in systemic lupus erythematosus (SLE). Besides cytomegalovirus, SARS-CoV-2 can induce pulmonary capillaritis to develop diffuse alveolar hemorrhage (DAH), a respiratory emergency of SLE.

Objective: Owing to lack of comprehensive studies for SARS-CoV-2-triggered DAH in SLE, we conducted a monocentric analysis with mechanistic investigation.

Methods: Hospitalized SLE patients were retrospectively analyzed for the DAH manifestation in the COVID-19 era since December 2019, focusing on those with preceding SARS-CoV-2 infection. Peripheral blood (PB) and lung tissues samples and immune/alveolus cell lines were used for mechanistic research.

Results: Twenty-five DAH episodes were identified in 21 SLE patients (3% occurrence), all in disease flares with high activity scores. During the domestic omicron variant outbreak, 7 patients (33%) had preceding SARS-CoV-2 infection, 3 to 7 weeks earlier to the onset of DAH, while they had elevated IL-6, nitro-oxidative stress- and cell death-associated molecules levels in PB and lung tissues with enhanced apoptosis formation. IL-6-stimulated alveolus/immune cells exhibited a dose-dependent increase in nitro-oxidative stress- and cell death-associated molecules levels, up-regulated p38MAPK/NF-κB-p65 phosphorylation, raised ROS expression and enhanced apoptosis formation. These findings implicated cell death induced by IL-6-activated nitro-oxidative stress to generate circulating immune complexes with pulmonary deposition as the mechanism for DAH preceded by SARS-CoV-2 infection in SLE.

Conclusion: The DAH manifestation preceded by SARS-CoV-2 infection is observed in SLE with disease flares, requiring careful monitor and management of COVID-19 in such patients.

Pertussis, caused by Bordetella pertussis, remains a substantial public health threat despite long-standing vaccination programs. Widespread non-pharmaceutical interventions (NPIs) during COVID-19 were accompanied by marked declines in reported pertussis activity in many settings. However, relaxation of containment measures has been followed by resurgence, characterized by atypical outbreak patterns and shifts in case distribution, bacterial genotypes, and affected populations. Emerging evidence suggests that these changes are multifactorial, including altered contact patterns and immunity gap, disruptions and recovery in routine immunization and surveillance, waning or suboptimal vaccine-induced protection, pathogen adaptation, and improved case detection through expanded diagnostic capabilities. Addressing these challenges will require coordinated strategies to restore and optimize immunization delivery, strengthen surveillance and laboratory capacity (including resistance monitoring), and update clinical management guidance in the context of macrolide-resistant B. pertussis. Continued research is needed to define setting-specific drivers and to inform next-generation vaccines and integrated control strategies in the post-pandemic era.

Background: Kawasaki disease (KD) is an acute febrile systemic vasculitis characterized by vascular inflammation. Its pathogenesis has been linked to the infiltration of IgA⁺ plasma cells within the respiratory tract, suggesting the upper airway may act as a potential portal of entry. However, evidence connecting respiratory infections to KD remains limited. This study aimed to explore the relationship between oral microbiota and KD development.

Methods: Oral swab samples were collected from 25 KD patients before and after intravenous immunoglobulin (IVIG) treatment, as well as from 25 healthy controls. Metagenomic sequencing was performed to characterize overall microbial composition and identify potential microbial markers associated with KD.

Results: Significant alterations in oral microbiota composition were observed between KD patients and healthy controls. The diversity of oral microbiota in KD patients was markedly lower than that in healthy controls, and exhibited an upward trend following IVIG treatment. Elevated levels of Streptococcus, Prevotella, and Veillonella, along with reduced levels of Haemophilus, Neisseria, and Rothia, were closely associated with KD development. Putative novel pathogen Abiotrophia defectiva was significantly enriched in patients with KD. Correlation analysis revealed that the relative abundances of several Haemophilus species were positively correlated with albumin levels in KD patients before IVIG treatment. Additionally, the anti-inflammatory bacterium Rothia mucilaginosa may play a protective role against the development of coronary artery lesions in KD.

Conclusion: These findings provide new evidence that distinct alterations in the oral microbiome are associated with KD development. Oral microbiota-based biomarkers may represent a potential strategy for KD therapy.

Background: Fragmented and siloed nature of healthcare data leads to insufficient recognition of infection control priorities and poor adherence to preventive measures. We evaluated the impact of a visualized and integrated online information system on the infection control practice and incidence of multidrug-resistant organisms (MDROs), antimicrobial consumptions, and clinical outcomes in a medical intensive care unit (ICU).

Methods: Patients hospitalized in one medical ICU during July 1, 2023, to November 30, 2024, were collected, and were analyzed by clinical outcomes, the incidence rate of healthcare-associated MDROs, and the antimicrobial consumptions before and after the implementation of Infection Control Map (ICM). Another ICU was selected as comparison.

Results: A total of 775 patients were included and divided into two periods: Pre-intervention period (n = 262), and Intervention period (n = 513). There were no statistical differences among demographics except the Acute Physiologic Assessment and Chronic Health Evaluation II (APACHE II) score, which was higher in the Intervention period than that of Pre-intervention period (30.0 vs 25.0, p = 0.000). The incidence rate of MDROs decreased over time (tau = -0.53, p = 0.019), especially the methicillin-resistant Staphylococcus aureus (1.5 vs 0.3 per 1000 patient-days, incidence rate ratio = 0.2, p = 0.012), as well as the consumption of meropenem (tau = -0.53, p = 0.003). There was significant decrease in 30-day all-cause mortality after the ICM use by multivariate analysis.

Conclusion: The implementation of the ICM significantly strengthened infection control practices, resulting in a marked reduction in healthcare-associated MRSA incidence, targeted antimicrobial usage, and 30-day all-cause mortality.

Background: Respiratory tract infections (RTIs) remain a major concern in pediatric care, as they can pose life-threatening risks to children. While SARS-CoV-2 receives substantial public concern, identifying other respiratory pathogens in SARS-CoV-2-negative patients is crucial for guiding clinical management.

Methods: In this study, the etiology of RTIs among 156 SARS-CoV-2-negative children in 2022 was analyzed using BIOFIRE® FilmArray® Respiratory Panel 2.1 assay, VIASURE rhinovirus + enterovirus detection kit, and an in-house realtime-PCR for human bocavirus.

Results: Of the 156 samples tested with the FilmArray®, 96 (61.5%) were positive for viral pathogens, with human rhinovirus/enterovirus (HRV/EV) being the most prevalent (92.7%). Targeted PCR assay confirmed that 97.8% of HRV/EV detections were rhinoviruses, which were significantly associated with asthma (OR = 9.0, 95% CI = 2.0-14.2, P = 0.005). Human bocavirus (HBoV) was detected in 40 out of 144 samples (27.8%) using real-time PCR. Multivariable analysis identified age as the only factor associated with HBoV detection (OR = 0.8, 95% CI: 0.7-1.0, P = 0.014), although it was noted 45.5% of pneumonia cases were HBoV-positive. Overall, 75.7% of co-detections involved HBoV, most frequently with HRV/EV. Co-detections were significantly associated with male gender (OR = 2.9, 95% CI = 1.2-7.3, P = 0.024) and fever (OR = 6.3, 95% CI = 2.0-19.8, P = 0.002).

Conclusion: Our study demonstrates the occurrence of viral co-detections in pediatric patients with non-SARS-CoV-2 RTIs during the pandemic. The frequent detection of rhinovirus and HBoV warrants further investigation into their clinical significance in Taiwanese children with RTIs.