Infection and Chemotherapy最新文献

Treatment with eculizumab increases the risk of invasive meningococcal infection (IMI). We evaluated tetravalent meningococcal vaccine responses in pediatric hematopoietic cell transplant (HCT) recipients with eculizumab for veno-occlusive disease (eculizumab group, n=4) and compared to patients with asplenia/polysplenia (asplenia/polysplenia group, n=2). Among the eculizumab group, two patients had a partial and full antibody response, respectively; two had no response. In contrast, the asplenia/polysplenia group showed full responses. These findings suggest poor vaccine response in HCT patients receiving eculizumab during the early post-HCT period, indicating limited meningococcal vaccine response and a need for antibiotic prophylaxis to prevent IMI in this group.

Background: Group B Streptococcus (GBS) is a major cause of invasive bacterial diseases, including sepsis, meningitis, and pneumonia, particularly in newborns and infants. Pregnant adults, those with pre-existing conditions, and older adults are particularly susceptible. Ongoing research is focused on developing various vaccines utilizing different antigens, including capsular polysaccharides and alpha-like proteins (Alps). Epidemiological data on these antigens in GBS is essential for predicting the effectiveness of these vaccines. However, no epidemiological studies on Alps genotype have been conducted in Korea. This study aimed to fill this gap by investigating the distribution and characteristics of the alp genotype in domestic clinical strains.

Materials and methods: We analyzed 386 GBS strains isolated from various clinical specimens between April 2000 and November 2018. The serotype of each strain was initially verified using a slide latex agglutination reaction, then confirmed by polymerase chain reaction to determine the presence of the genes bca, rib, alp1, alp2, alp3, and alp4 associated with Alps. Strains were then classified as invasive or non-invasive based on the type of clinical specimen. The distribution of serotypes and alp genotype was analyzed across these classifications.

Results: We analyzed 386 bacterial strains to assess their clinical characteristics, serotypes, and alp genotype distributions. Of these strains, 47.1% (182 strains) were invasive primarily isolated from blood samples (43.3%, 167 strains), whereas non-invasive strains were more frequently isolated from sites such as the vagina and urethra. Serotype III was the most prevalent across both invasive and non-invasive strains, comprising 28.2% (109 strains) of all isolates. Notably, 79.5% (307 strains) of all isolates were encompassed by the hexavalent vaccine (serotype Ia, Ib, II, III, and V) formulations. Furthermore, the rib genotype was the most common, detected in 39.4% (152 strains) of all isolates, with a higher prevalence in non-invasive samples (44.1%, 90 strains).

Conclusion: Although the distribution of alp genotypes differed between invasive and non-invasive strains, the proportion of bca and rib was substantial. Therefore, Alp protein vaccine containing Rib and Cα antigens is expected to provide protection against prevalent GBS strains in Korea. Additional epidemiological studies on GBS vaginal colonization in pregnant women and invasive neonatal strains are needed to support early neonatal sepsis prevention in these high-risk groups.

Background: The increasingly widespread use of antiretroviral drugs (ARV) to manage human immunodeficiency virus (HIV) infection has significantly reduced mortality. Accordingly, the number of patients with HIV with a life expectancy >50 years is increasing. With advanced age, the risk of non-communicable diseases (NCD) increases. According to a study in Uganda in 2017, the prevalence of at least one NCD in patients with HIV was 20.7%, with 11-30% of deaths due to NCDs, especially cardiovascular disease. This emphasizes that NCDs in patients with HIV are of clinical concern, as are the factors that increase the risk of these diseases. However, most studies on HIV and NCDs focus on African countries, while research in Asia is limited. Differences in genetics, lifestyle, and co-existing health burdens may influenced NCD prevalence and risk factors. This study aimed to determine the prevalence of and risk factors for NCDs in patients with HIV.

Materials and methods: This was an analytical cross-sectional study conducted at the outpatient clinic of the Ngoerah Hospital from June 8, 2023, to July 7, 2023. Descriptive and multivariate analyses were performed.

Results: In total, 1,644 patients with HIV were included in this study. The prevalence of NCDs was 1.9% for hypertension, 1.1% for diabetes mellitus, 0.7% for dyslipidemia, 1.0% for kidney disorders, 0.1% for stroke, 0.3% for cancer, 0.3% for cardiovascular disease, and 0.2% for autoimmune diseases. After conducting a multivariate test, we found that age >50 years increased the risk of comorbid NCDs by 7.886 times, while male sex increased the risk by 2.568 times, and an ARV regimen of two nucleoside reverse transcriptase inhibitors (NRTIs) + non-NRTI (NNRTI) decreased the risk by 2.625 times.

Conclusion: Hypertension was the most common NCD in patients with HIV, followed by diabetes mellitus. Male patients and those aged >50 years were at a greater risk of developing NCDs, whereas a history of using the two NRTIs + NNRTI regimen was associated with a lower risk of NCDs.

Background: Phylogenetic studies are essential for understanding the virulence and resistance factors of bacteria, especially in evaluating their distribution within specific populations for effective infection control. Urinary tract infections (UTIs) caused by Escherichia coli are highly prevalent and pose significant health challenges from childhood to adulthood. The rising incidence of multidrug-resistant (MDR) strains highlights the urgent need for research aimed at developing preventive measures and epidemiological control strategies. This study aimed to analyze phylogenetically uropathogenic E. coli strains and their resistance phenotypes in children.

Materials and methods: A retrospective analysis was conducted on 111 urine culture samples collected from June 2023 to February 2024 at the Pediatric Emergency Hospital (PEH) in Lima, Peru. The phylogroups of E. coli were identified using Clermont's protocol based on polymerase chain reaction.

Results: UTIs were predominantly observed in females (85.6%) and infants under two years old (42.3%). The most frequent uropathogenic E. coli phylogroups were B2 (30.6%), D (29.7%), and A (25.2%). These phylogroups showed significant correlation with MDR and the production of extended spectrum beta-lactamases (ESBL).

Conclusion: At PEH, UTIs in children are primarily caused by uropathogenic E. coli from the B2 and D phylogroups, which demonstrate high virulence and resistance factors. The correlation between these phylogroups, MDR, and ESBL production, along with the increasing infection rates associated with phylogroup A, suggests a potential for horizontal gene transfer. This underscores the urgent need for vigilant control measures.

Background: Severe acute respiratory syndrome coronavirus 2, an RNA virus, exhibits variations in transmission power, severity rate, and vaccine effectiveness due to its mutable nature. We investigated the field epidemiological characteristics of the delta and omicron variants of coronavirus disease 2019 (COVID-19) clusters in a long-term care hospital.

Materials and methods: This study aimed to investigate the incidence, fatality, and vaccination effectiveness of confirmed COVID-19 cases caused by delta and omicron variants. The investigation focused on patients admitted to two long-term care hospitals in a Seoul autonomous district, comparing and analyzing relevant factors.

Results: Among the COVID-19 cases, 101 (34.3%) exhibited delta variants, while 193 (65.4%) showcased omicron variants. The incidence rate of omicron variants, compared to delta variants, was 2.24 times higher (95% confidence interval [CI], 1.68-3.00). This elevation was particularly notable in women across all age groups, patients, workers, and individuals with a history of three or more vaccinations. Deaths were reported in 13 cases (52.0%) with the delta variant and 12 cases (48.0%) with the omicron variant. The fatality rate of the omicron variant, in comparison to the delta variant, was 0.09 times (95% CI, 0.44-2.26), indicating no significant difference. No discernible variations in variables were observed.

Conclusion: The noteworthy surge in outbreaks among female patients, workers engaged in outdoor activities, and the apparent ineffectiveness of vaccination against omicron mutations underscore the need for careful consideration in formulating quarantine measures.

We report linezolid-resistant coagulase-negative Staphylococcus (LRCoNS) bacteremia at a tertiary hospital. LRCoNS with linezolid and tedizolid minimum inhibitory concentrations of >32 and 4-32 mg/L, respectively, were isolated from blood cultures of seven elderly patients who died post-bacteremia detection. Linezolid was administered to six of these patients at the time of LRCoNS isolation. Linezolid-resistant S. epidermidis ST5 isolates (LRSE) harboring mecA were isolated in seven of the nine episodes. Linezolid resistance is associated with mutations in the 23S rRNA, L3 and L4 ribosomal proteins, indigenous methyltransferases RlmN, and the presence of the cfr gene. All LRSE-ST5 genomes formed a single phylogenetic cluster.

Respiratory syncytial virus (RSV) poses a significant threat to infants and young children in Korea and globally. Current preventive measures, such as palivizumab, have limitations, necessitating the exploration of new strategies. Nirsevimab, a long-acting monoclonal antibody, has emerged as a promising option for protecting all infants from RSV. Clinical trials and real-world evidence support its effectiveness in reducing RSV-related hospitalizations. The economic burden of RSV infection in Korea underscores the need for cost-effective interventions. While several RSV vaccines are under development, none are currently available in Korea. Maternal immunization programs and vaccines for older infants offer potential avenues for expanding protection. This review highlights the evolving landscape of RSV prevention, with a shift towards nirsevimab and future vaccines. Further research is crucial to understand the long-term consequences of RSV infection and develop comprehensive prevention strategies tailored to the Korean population.

Background: This study compared the mortality rates within 30 days of 2 different doses of sulbactam (6 g and 9-12 g daily) when used in colistin (COL)-based treatment regimens and COL monotherapy for carbapenem-resistant Acinetobacter baumannii (CRAB).

Materials and methods: This retrospective cohort study included 234 participants diagnosed with severe pneumonia due to CRAB infection at Phramongkutklao Hospital, Thailand, from July 1, 2011, to April 30, 2023. Participants were categorized into three groups: COL monotherapy, COL with 6 g of sulbactam daily (COL+S6g), and COL with 9-12 g of sulbactam daily (COL+SHD). Following the exclusion of patients with renal impairment (serum creatinine ≥1.5 mg/dl), a 1:2 propensity score (PS) matching was used to ensure comparable groups, with the COL group designated as the control. The matching variables included age, APACHE II scores, serum creatinine, intensive care units admission, and bacteremia. The number of participants in each group was as follows: 19 in COL, 32 in COL+S6g, and 38 in COL+SHD. The primary outcomes assessed were all-cause mortality rates at 7, 14, and 30 days. Kaplan-Meier survival curves and the Log-rank test were used to evaluate differences between groups, while multivariate Cox regression models were applied to determine the impact of treatment regimens.

Results: The unmatching PS analysis indicated that the COL+SHD regimen significantly reduces mortality compared to the COL regimen; hazard ratios (HR) were 0.18 (95% confidence interval [CI], 0.06-0.55) for 7-day mortality and 0.53 (95% CI,-0.29-0.97) for 30-day mortality. In addition, the COL+SHD regimen also lowered mortality more than the COL+S6g regimen within 7 days (HR, 0.29; 95% CI, 0.11-0.75). After PS matching, the COL+SHD regimen significantly reduced 7-day mortality compared to the COL regimen (adjusted HR, 0.24; 95% CI, -0.07-0.82). However, COL+S6g did not differ in mortality from either COL+SHD or COL for 7-day mortality. At 14 days and 30 days, there were no significant regimens to reduce mortality.

Conclusion: Combining COL+SHD effectively reduced death in 7 days from severe pneumonia in CRAB infection treatment.