Journal of Infection and Chemotherapy最新文献

Objectives: In antimicrobial therapy, early intravenous-to-oral switch (IVOS) is recommended for eligible patients to minimize complications and optimize pharmacoeconomic outcomes. This study aimed to evaluate the impact of a clinical pharmacist-led multimodal intervention strategy on IVOS rates.

Methods: A prospective before-and-after study was conducted between January and June 2024, including observation and intervention periods. Hospitalized adults receiving IV antimicrobials were included. A two-round expert panel was convened prior to data collection to identify the criteria for IVOS. During the observation period, IV antimicrobial utilization patterns were monitored without intervention. The intervention period involved the implementation of a standardized IVOS protocol, targeted education for infectious disease physicians, and switch recommendations for eligible treatments. The primary endpoint was the difference in IVOS rates between study periods among eligible treatments.

Results: Among 962 IV antimicrobial courses evaluated, 213 (22.1%) met the eligibility criteria for IVOS. Among patients who met IVOS eligibility criteria, the proportion undergoing overall IVOS increased from 29.0% in the observation period to 54.0% in the intervention period (p < 0.001). Among 113 IVOS-eligible cases, pharmacists recommended switching in 57 (50.4%), with a 59.6% physician acceptance rate (34/57). No significant differences were observed between periods for: microbiological cure rates, Clostridioides difficile infection incidence, intensive care unit admission rates, antimicrobial reinitiation within 48 h of treatment cessation, 15- and 30-day readmission and mortality rates. Antimicrobial costs decreased significantly from $15,600.30 (all-parenteral baseline) and $14,997.40 (adjusted baseline) to $8333.81 post intervention.

Conclusions: The intervention was associated with a substantial increase in overall IVOS among eligible patients, supporting its effectiveness in promoting timely de-escalation from intravenous therapy. Clinical pharmacist-led initiatives optimize appropriate switching and antimicrobial utilization in stewardship.

Introduction: Positive preoperative urine culture is a risk factor for infection after ureteroscopic lithotripsy (URSL). However, the effectiveness of tailoring antimicrobial prophylaxis (AP) to pathogens identified in preoperative urine culture remains unclear. This study aimed to evaluate whether three AP strategies reduce bloodstream infections and sepsis following URSL.

Methods: This single-center retrospective observational study was conducted between April 2019 and March 2025 at Komaki City Hospital, Japan. AP was classified into three categories: guideline-compliant AP (GC-AP, which do not cover all detected pathogens), pathogen-directed AP (PD-AP, which cover all pathogens but is non-guideline-compliant), and enhanced GC-AP (GC-AP or AP with an extended spectrum of antibiotics to which all pathogens detected in the preoperative urine culture are susceptible). The incidences of bloodstream infections and sepsis after URSL were compared among the three groups. The risk factors for postoperative sepsis were analyzed using multivariable logistic analysis.

Results: The enhanced GC-AP group had fewer bloodstream infections than the GC-AP group (0.67% [1/149] vs. 8.11% [6/74], p = 0.0059). No bloodstream infections were observed in the PD-AP group. However, the incidence of sepsis was significantly higher in the PD-AP group than in the enhanced GC-AP group (28.6% [8/28] vs. 10.7% [16/149], p = 0.030). Multivariable analysis showed that enhanced GC-AP significantly reduced the incidence of sepsis after URSL (odds ratio: 0.41, 95% confidence interval: 0.18-0.93, p = 0.023).

Conclusions: Enhanced GC-AP reduced bloodstream infections and sepsis after URSL.

Introduction: Marine microorganisms are rich in bioactive compounds having biotechnological significance. Hydrothermal vents are specifically home to unique microbial communities that have the ability to produce diverse compounds with therapeutic potential. This study aimed to isolate and characterize bioactive proteins from marine Bacillus sp. with antibacterial and anti-inflammatory properties and to evaluate their efficacy.

Methods: Bacillus sp. isolated from hydrothermal vents, have been grown optimally, with the partially purified extracellular protein fraction separated by ammonium sulfate precipitation and Sephadex G-10 gel filtration. The antimicrobial property was determined against the Methicillin-resistant Staphylococcus aureus (MRSA) and Vibrio vulnificus, with temperature stability studies conducted on the proteins. Zebrafish infection assays, together with lipopolysaccharide (LPS) challenges, served to determine the biological activity.

Results: A thermostable protein with a molecular weight of ⁓ 55 kDa showed strong inhibitory effects against MRSA and V. vulnificus. In the infection models using zebrafish, administration of the protein extract led to a substantial increase in survival rates (P < 0.01). Besides, a reduction in mRNA expression of pro-inflammatory cytokines (IL-1β, IL-6, TNF-α) was observed using RT-PCR analysis.

Conclusion: The thermostable Bacillus sp. protein exhibited both antibacterial and anti-inflammatory properties, indicating its potential for scale-up and biotherapeutic use.

Cutibacterium acnes is a low-virulence skin commensal that can cause late-onset prosthetic graft infections. We report the case of a 60-year-old man with diabetes who presented with fever and bilateral chest pain 10 months after an ascending aortic graft replacement. Computed tomography revealed right-sided pleural effusion and perigraft fluid collections; extended incubation of the pleural fluid and blood samples revealed C. acnes. Seven weeks after the intravenous antibiotic therapy, the patient underwent mediastinal irrigation, explantation of the infected graft, replacement with a rifampicin-soaked prosthesis, and omental flap coverage. Extended incubation of intraoperative specimens resulted in C. acnes in both samples. Following four additional weeks of intravenous antibiotic therapy, long-term oral amoxicillin suppression was initiated. At one-year follow-up, the patient remained clinically stable without evidence of recurrence. This case highlights the importance of extended incubation, vigilant diagnostic evaluation, and combined surgical and antimicrobial management in delayed C. acnes vascular graft infections. We also reviewed relevant literature on C. acnes prosthetic vascular infections to contextualize this case.

Background: In adults, cefepime is proposed as a treatment option for infections associated with a risk of AmpC β-lactamase overproduction; however, data in pediatric populations are limited. We aimed to compare clinical outcomes between cefepime versus carbapenem as definitive therapy for bacteremia caused by Enterobacterales with a relatively high risk of chromosomal AmpC production (AmpC-E) in children.

Methods: This retrospective cohort study was conducted at a tertiary children's hospital between 2010 and 2024. Eligible patients were <21 years old with blood cultures positive for AmpC-E. The primary outcome was 30-day mortality. Secondary outcomes included 30-day recurrence, time to negative blood culture and treatment-related toxicity.

Results: 51 children met the inclusion criteria. The median age was 11 months (IQR: 3-63), with 54.9% male patients. Cefepime and meropenem were administered as definitive therapy in 38 (74.5%) and 13 (25.5%) cases. Baseline characteristics of the patients were comparable. Isolated organisms included Enterobacter cloacae complex (47.1%), Serratia marcescens (29.4%) and Klebsiella aerogenes (19.6%). The cefepime group had a higher prevalence of Klebsiella aerogenes (26.3%, p = 0.048) and Serratia marcescens (39.5%, p = 0.006). The 30-day mortality was 2.6% (1/38) in the cefepime group and 15.4% (2/13) in the meropenem group (p = 0.156). No recurrence of bacteremia or treatment-related toxicity were observed. The median time to negative blood cultures was 2 days (IQR: 1-3) in the cefepime group and 1 day (IQR: 1-5) in the meropenem group (p = 0.949).

Conclusion: Cefepime and meropenem as definitive therapy demonstrated comparable outcomes for AmpC-E bacteremia. Further prospective studies are warranted.

Purpose: Small-colony variants (SCVs) are a slow-growing subset of bacteria that exhibit unusual colony morphology and unique biochemical characteristics. They are associated with chronic and persistent infections. CO₂-dependent SCVs of Staphylococcus aureus have been rarely isolated from clinical specimens. This study aimed to characterize the CO₂-dependent phenotype of S. aureus SCV isolated from pacemaker leads and to determine the genetic basis underlying this trait.

Methods: CO₂-dependent S. aureus SCV-5700 isolated from pacemaker leads of a patient with a pacemaker infection was used in this study. Phenotypic testing, antimicrobial susceptibility testing, and mecA polymerase chain reaction of the isolate were performed. Moreover, whole-genome sequencing was conducted for multilocus sequence typing and comparative genomic analysis.

Results: CO₂-dependent S. aureus SCV-5700 grew poorly under ambient air conditions; however, tiny colonies formed after 48 h incubation. The isolate was sequence type 45 and did not harbor the mecA. The isolate was identified as S. aureus by biochemical characterization in a 5 % CO₂ atmosphere. Comparative genomic analysis revealed that the isolate had a nonsense mutation (c.565C>T) in the mpsB; however, the revertant strain, Rev-5700, had no such mutation.

Conclusion: The CO₂-dependent phenotype of clinical S. aureus isolates can be attributed, in part, to loss of MpsB function.