Infection and Chemotherapy最新文献

Background: The coronavirus disease 2019 (COVID-19) pandemic has led to many changes in medical practice. For example, some adult studies have reported that the strict implementation of universal precautions increased blood culture contamination rates. However, little evidence exists in children, and its relevance to pediatrics remains unclear.

Materials and methods: This retrospective observational study was conducted at a tertiary children's hospital in Japan where the emergency department (ED) physicians receive active monthly feedback for changes in blood culture contamination rates. The data were extracted from medical records of children under 18 years old. The number of patients who visited the ED, number of blood culture bottles drawn, results of positive blood cultures, and sources of infection were compared between the pre-COVID-19 (1/2017-12/2019) and COVID-19 (1/2020-12/2022) periods.

Results: During each period, 83,224 and 57,742 patients visited the ED, and 12,571 and 9,409 blood cultures were obtained, respectively. The contamination rates were unchanged, with average rates of 1.0% in both periods (P=0.54). Occult bacteremia decreased (from 36 to 9 cases; P=0.015), and the proportion of bacteremia attributable to respiratory pathogens also declined (P=0.015).

Conclusion: Active feedback is likely to maintain low contamination rates during the pandemic. The decrease in occult bacteremia suggests that enhanced infection control measures influenced pediatric infectious disease patterns.

Background: Data on coinfection with Aspergillus and Mucorales are limited, although identifying such coinfection is important for its management. The diagnosis of mucormycosis remains challenging owing to the lack of reliable antigen tests and the low sensitivity of fungal culture, especially when biopsy is not feasible. Thus, we investigated mucormycosis coinfection in cases of proven or probable aspergillosis, using plasma Mucorales polymerase chain reaction (PCR).

Materials and methods: Adult patients with proven or probable aspergillosis who consented to blood sampling were prospectively enrolled at a tertiary hospital between January 2017 and April 2020, and again between June 2023 and February 2025. Aspergillosis was classified according to the European Organization for Research and Treatment of Cancer/Mycosis Study Group (EORTC/MSG) criteria. Plasma 18S PCR was performed to detect Aspergillus- and Mucorales-specific DNA.

Results: A total of 82 patients (28 with proven and 54 with probable aspergillosis) were analyzed. No Mucorales were detected in sterile or non-sterile cultures. Among the 28 patients with proven aspergillosis, 4 (14.3%) showed evidence of mucormycosis coinfection: 2 had a positive Mucorales-specific PCR result, and 2 had positive PCR results for both Aspergillus and Mucorales. Among the 54 patients with probable aspergillosis, 12 (22.2%) showed evidence of mucormycosis coinfection: 7 had a positive Mucorales-specific PCR result, and 5 had positive results for both Aspergillus and Mucorales. Overall, 16 (19.5%) of the 82 patients with proven or probable aspergillosis showed molecular evidence of possible mucormycosis coinfection. In-hospital mortality did not significantly differ between patients with mucormycosis coinfection who were treated with voriconazole and those with aspergillosis alone treated with voriconazole (38.5% [5/13] vs. 30.6% [15/49]; P=0.74).

Conclusion: Approximately 10-20% of patients with proven or probable aspergillosis had molecular evidence of possible mucormycosis coinfection, as detected by plasma Mucorales PCR.

The Korean Society of Infectious Diseases has regularly updated its adult immunization guidelines, including the coronavirus disease 2019 (COVID-19) vaccination recommendations in 2023 and the 2024-2025 seasonal update. This article provides a comprehensive update as of September 2025, reflecting the latest evidence and international guidance. Focusing on the 2025-2026 season, it reviews vaccines currently authorized in Korea and their effectiveness against predominant JN.1 sublineage variants, including LP.8.1, NB.1.8.1, and XFG. The updated recommendations prioritize vaccination with LP.8.1-adapted vaccines for high-risk groups-adults aged 65 years and older, individuals aged 6 months and older at increased risk for severe disease, and residents of facilities vulnerable to infection-while vaccination remains available for all individuals aged 6 months and older. A single-dose strategy is generally recommended, although older adults and immunocompromised individuals may consider an additional dose at 6-month intervals in consultation with healthcare professionals. These updates aim to refine Korea's COVID-19 vaccination strategy and sustain protection in high-risk populations, with recommendations remaining subject to revision as new evidence and epidemiological conditions evolve.

Background: Beta-lactam allergy (BLA) labels are common in pediatric patients but are often inaccurate, leading to unnecessary use of second-line antibiotics. While direct oral challenge tests (OCTs) are effective for de-labeling, their implementation in inpatient pediatric settings remains underexplored. This study aimed to evaluate the feasibility and barriers of an inpatient pediatric BLA de-labeling program, from bedside OCT to long-term follow-up and integration into electronic medical records (EMRs).

Materials and methods: We conducted a prospective interventional study in the pediatric ward between 2019 and 2024. Hospitalized children with a documented BLA were screened and eligible patients underwent a 2-step graded OCT. In-house pediatricians completed surveys to assess beliefs and barriers regarding inpatient OCT implementation. Long term follow-up included caregiver surveys and review of hospital and Health Maintenance Organization (HMO) EMRs to evaluate de-labeling documentation and subsequent beta-lactam use.

Results: Of 192 eligible BLA-labeled patients, 32 (16.6%) were recruited, 93.8% carrying an amoxicillin allergy label and the vast majority without other drug allergy labels. All patients had a history of a mild reaction, 100% presented with a benign rash. 30/32 (93.4%) had a negative OCT. Pediatricians faced challenges such as workload pressures, staff shortages and overestimation of severe reaction risks, all serving as barriers for patient recruitment. At follow-up (median 37 months), 35.7% of caregivers reported de-labeling, while EMRs documented higher rates (HMO: 80%l; hospital: 70%). Despite successful OCTs, discrepancies between caregiver understanding, physician attitudes, and EMR documentation persisted.

Conclusion: While direct OCTs are proved to be effective in de-labeling BLA, significant challenges persist in implementing inpatient de-labeling and ensuring their long-term success. These include low recruitment rates, pediatricians' misconceptions and incomplete integration into EMRs. Addressing these barriers requires targeted education, improved communication, and streamlined processes to improve de-labeling outcomes and support antibiotic stewardship.

Background: Non-alcoholic fatty liver disease is increasing worldwide, and sepsis remains a major global health challenge owing to its high mortality. Given the lack of specific therapeutic agents for sepsis, identifying high-risk populations and implementing preventive measures are critical. This study aimed to investigate the association between a single-time fatty liver index (FLI) measurement and the long-term risk of sepsis.

Materials and methods: The cohort included participants from the 2009 Korean National Health Screening Program with no excessive alcohol consumption or acute or chronic liver diseases. The FLI was calculated at baseline and categorized into three groups: low (<30), moderate (30-60), and high (>60). The subjects were followed-up for up to 10 years until sepsis diagnosis or death. Patients with sepsis identified during the washout and one-year lag periods were excluded.

Results: Of 3,222,171 participants, 64,226 (2.0%) developed sepsis during the follow-up period. The incidence rates per 1,000 person-years in the low-, moderate-, and high-FLI groups were 1.68, 2.52, and 2.58, respectively. In the multivariable Cox regression model, the high-FLI group had a significantly increased risk of sepsis, with an adjusted hazard ratio of 1.52 (95% confidence interval, 1.49-1.55) compared with the low-FLI group. Restricted cubic spline analysis showed a J-shaped nonlinear relationship between FLI and sepsis with increased sepsis risk above an FLI of 23.6.

Conclusion: This large-scale, long-term observational study demonstrated a significant association between single-time FLI measurement and sepsis risk, highlighting the potential role of FLI in early risk stratification and the prevention of sepsis.

Owing to concern that carbapenemase-producing strains among carbapenem-resistant Pseudomonas aeruginosa (CRPA) isolates is on the rise, we investigated the genetic epidemiology and antimicrobial susceptibilities of clinical CRPA isolates collected in four academic hospitals in Korea. Carbapenemase genes were detected in 46 of 63 CRPA isolates (73.0%) collected between 2021 and 2024, and bla_NDM ST773 was the most common genotype (27 isolates, 42.9%), followed by bla_NDM ST644 (9 isolates, 14.3%) and bla_IMP ST235 (7 isolates, 11.1%). Overall susceptibility to ceftazidime/avibactam was only 17.5%, and none of the carbapenemase-producing isolates were susceptible to it. All ST644 strains were also resistant to aztreonam.