{"title":"Refractory invasive pulmonary aspergillosis caused by two Aspergillus species in an allogeneic hematopoietic stem cell transplantation recipient","authors":"Mizuki Haraguchi , Otoya Watanabe , Muneyoshi Kimura , Sho Ogura , Takashi Umeyama , Yasunori Muraosa , Ami Koizumi , Takayuki Shinohara , Yoshitsugu Miyazaki , Go Yamamoto , Hideki Araoka , Naoyuki Uchida","doi":"10.1016/j.jiac.2025.102751","DOIUrl":"10.1016/j.jiac.2025.102751","url":null,"abstract":"<div><div>Invasive fungal infections are critical complications in patients with hematological malignancies. Herein, we report a case of refractory invasive pulmonary aspergillosis (IPA) caused by two <em>Aspergillus</em> species in a recipient of hematopoietic stem cell transplantation. Repeated sputum cultures revealed causative pathogens, which were identified as <em>Aspergillus terreus</em> and <em>Aspergillus flavus</em>. The antifungal susceptibility testing showed that these <em>Aspergillus</em> species had a high minimal inhibitory concentration against amphotericin B, suggesting that they caused the refractory infection in this patient. Although the patient was treated with a combination of isavuconazole and micafungin, the IPA worsened, and the patient died due to multiple organ failure. The findings from this case highlight the complexity of refractory invasive fungal infections, wherein multiple fungal species can simultaneously affect patients, particularly those with severely compromised immune function. Further investigation is urgently required to improve the management strategies for refractory IPA, including early pathogen identification and novel antifungal agent development.</div></div>","PeriodicalId":16103,"journal":{"name":"Journal of Infection and Chemotherapy","volume":"31 8","pages":"Article 102751"},"PeriodicalIF":1.9,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144275107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mayuko Kawamura , Daisuke Ono , Takayuki Kawamura , Kazuyuki Mimura , Eiyu Ebata , Bin Chang , Yukihiro Akeda , Akihiro Yoshitake , Kotaro Mitsutake , Hideaki Oka
{"title":"A case of infectious endocarditis and vertebral discitis caused by Streptococcus pneumoniae serotype 23A","authors":"Mayuko Kawamura , Daisuke Ono , Takayuki Kawamura , Kazuyuki Mimura , Eiyu Ebata , Bin Chang , Yukihiro Akeda , Akihiro Yoshitake , Kotaro Mitsutake , Hideaki Oka","doi":"10.1016/j.jiac.2025.102749","DOIUrl":"10.1016/j.jiac.2025.102749","url":null,"abstract":"<div><div><em>Streptococcus pneumoniae</em>, is a Gram-positive diplococcus, causes various community-acquired infections. Although pneumococcal vaccination has reduced the incidence of invasive pneumococcal disease, relative incidence of non-vaccine serotype-associated infections has increased. Herein, we report a case of pneumococcal infectious endocarditis and vertebral discitis diagnosed concurrently. A 73-year-old man presented with a 1-week history of fever and back pain (day 0). Laboratory tests revealed elevated inflammatory markers and magnetic resonance imaging confirmed vertebral osteomyelitis. Empirical intravenous cefazolin and vancomycin were initiated, considering appropriate coverage for common causative organisms of vertebral osteomyelitis. On day 1, blood cultures yielded <em>S. pneumoniae</em>— later identified as penicillin G susceptible serotype 23A belonging to sequence type 5242 —and antibiotics were switched to ceftriaxone and vancomycin. On the same day, the patient developed worsening oxygenation and a systolic murmur. Echocardiography revealed a mitral valve vegetation with severe regurgitation. Cefepime and vancomycin were initiated on day 2, followed by meropenem and vancomycin on day 4 for potential nosocomial pneumonia. On day 6, cefepime monotherapy was continued after methicillin-resistant <em>Staphylococcus aureus</em> was not detected in sputum culture. To address persistent respiratory failure, mitral valve replacement was performed on day 7. Cultures of tissue removed from the mitral valve were negative; 16S rRNA sequencing using the excised valve confirmed <em>S. pneumoniae</em> infection. Postoperatively, ceftriaxone was resumed, followed by oral levofloxacin, and a 42-day antimicrobial course was completed. The patient recovered without any recurrence. Continued surveillance of pneumococcal serotypes and antimicrobial resistance is warranted.</div></div>","PeriodicalId":16103,"journal":{"name":"Journal of Infection and Chemotherapy","volume":"31 8","pages":"Article 102749"},"PeriodicalIF":1.9,"publicationDate":"2025-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144254121","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Candida auris clade I isolates from ear discharge in Japan demonstrated comparable virulence to invasive clade I isolates against Galleria mellonella","authors":"Sayoko Oiki , Masahiro Abe , Sota Sadamoto , Kazuki Amemiya , Takayuki Shinohara , Amato Otani , Ami Koizumi , Takashi Umeyama , Koichi Makimura , Yoshitsugu Miyazaki","doi":"10.1016/j.jiac.2025.102747","DOIUrl":"10.1016/j.jiac.2025.102747","url":null,"abstract":"<div><h3>Introduction</h3><div><em>Candida auris</em> is one of the most serious fungal pathogens in the world due to its characteristics of multidrug resistance and causing outbreaks in hospitals. Based on genetic analysis through whole-genome sequencing, <em>C. auris</em> has been classified into four major clades. In Japan, most strains were isolated from noninvasive ear discharge and classified into clade II, whereas clades I, III, and IV are typically detected in patients with invasive candidiasis worldwide. However, three strains, NIIDFCaurisB0004, LSEM 3732, and LSEM 4020, were isolated from ear discharge in Japan and classified into clade I, and their virulence remains unknown. Here, we demonstrate the virulence of these ear discharge-derived clade I strain using the <em>Galleria mellonella</em> infection model.</div></div><div><h3>Methods</h3><div>Survival analysis, histopathological analysis, and colony count measurements of <em>G. mellonella</em> larvae infected with <em>C. auris</em> were conducted to compare the virulence of ear discharge-derived clade I strains, ear discharge-derived clade II strains, and non-ear discharge-derived clade I strains.</div></div><div><h3>Results</h3><div>Ear discharge-derived clade I strains exhibited higher mortality rates than ear discharge-derived clade II strains, comparable to those of invasive clade I strains. Histopathological analysis and colony count measurements revealed that the ear discharge-derived clade I strain, NIIDFCaurisB0004, exhibited significantly more growth than clade II strains in <em>G. mellonella</em>.</div></div><div><h3>Conclusion</h3><div>Even if <em>C. auris</em> is isolated from ear discharge in Japan, there exists a possibility that it can be classified into clade I with high virulence. Therefore, detailed identification of the clade is essential.</div></div>","PeriodicalId":16103,"journal":{"name":"Journal of Infection and Chemotherapy","volume":"31 8","pages":"Article 102747"},"PeriodicalIF":1.9,"publicationDate":"2025-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144248264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Vancomycin-associated acute kidney injury and its clinical and economic impact: a retrospective cohort study using two Japanese healthcare databases","authors":"Shutaro Murakami , Azusa Ishiyama , Sayuri Otogawa , Ryoko Sakai , Manabu Akazawa","doi":"10.1016/j.jiac.2025.102744","DOIUrl":"10.1016/j.jiac.2025.102744","url":null,"abstract":"<div><h3>Background</h3><div>Previous studies examining vancomycin-associated acute kidney injury (AKI) were methodologically limited. We herein investigated the AKI incidence, clinical outcomes, and economic impact of this condition on Japan's aging population using a robust, methodological approach to analyze information from two, large-scale, Japanese, healthcare databases.</div></div><div><h3>Methods</h3><div>This retrospective cohort study analyzed data on 2007 and 2607 patients aged ≥18 years and registered with the Medical Data Vision (MDV) database and the JMDC, Inc. database, respectively, who received vancomycin ≥4 days. Target trial emulation was employed with 1:1 propensity score matching to compare the outcomes of patients with and without AKI. The primary outcomes included 30-day in-hospital mortality, length of hospital stay (LOS), and direct medical costs. The KDIGO guidelines’ definition of AKI was used.</div></div><div><h3>Results</h3><div>AKI occurred in 19.4 % (MDV) and 14.9 % (JMDC) of the cohorts with the median onset being five days. After propensity score matching (386 and 387 pairs for MDV and JMDC, respectively), the AKI group demonstrated significantly higher 30-day in-hospital mortality (odds ratio: 3.82 [95 % confidence interval (CI): 2.52–5.79] for MDV; 4.36 [95 % CI: 2.89–6.57] for JMDC; both P < .001), prolonged LOS (hazard ratio: 1.45 [95 % CI: 1.22–1.72] for MDV; 1.79 [95 % CI: 1.35–2.37] for JMDC; both P < .001), and higher daily direct medical costs per patient (cost ratio: 1.39 [95 % CI: 1.19–1.62] for MDV; 1.33 [95 % CI: 1.18–1.50] for JMDC; both P < .001).</div></div><div><h3>Conclusions</h3><div>Vancomycin-associated AKI significantly increased mortality, prolonged hospitalization, and elevated healthcare costs. These findings can provide further impetus to effective vancomycin stewardship.</div></div>","PeriodicalId":16103,"journal":{"name":"Journal of Infection and Chemotherapy","volume":"31 7","pages":"Article 102744"},"PeriodicalIF":1.9,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144223142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Multifocal pyogenic arthritis and osteomyelitis with bacteremia caused by Streptobacillus notomytis: A case report and comprehensive literature review","authors":"Shun Yonezaki , Masumi Suzuki Shimizu , Takashi Sugimoto , Shotaro Ide , Yusuke Nakazoe , Akihiko Yonekura , Yasuhide Kawamoto , Norihiko Akamatsu , Kosuke Kosai , Katsunori Yanagihara , Koya Ariyoshi , Akitsugu Furumoto","doi":"10.1016/j.jiac.2025.102746","DOIUrl":"10.1016/j.jiac.2025.102746","url":null,"abstract":"<div><div><em>Streptobacillus notomytis</em>, recently recognized as a distinct species from <em>Streptobacillus moniliformis—</em>the primary causative agent of rat-bite fever—has been implicated in rare human infections. To date, there are no documented cases of femoral and tibial osteomyelitis attributable to this pathogen. Herein, we report a case of multifocal pyogenic arthritis and osteomyelitis involving the femur and tibia with bacteremia caused by <em>S. notomytis</em>, alongside a review of human infections associated with this organism. A 73-year-old woman initially presented with left knee pain at another hospital, where a filamentous gram-negative bacillus was isolated from joint aspirate and blood cultures. After developing sepsis, she was transferred to our facility. On admission, she had tenderness in both shoulder joints and swelling in the right fingers and wrist. Arthroscopic lavage was performed, and empirical antibiotics were initiated. Further analysis of the original isolates using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) identified <em>S. moniliformis</em> with a low confidence score of 1.6. Magnetic resonance imaging confirmed osteomyelitis of the femur and tibia. After 9 weeks of targeted therapy, the patient fully recovered ambulatory function. Subsequent 16S rRNA gene sequencing definitively identified the pathogen as <em>S. notomytis</em>. These findings highlighted that in cases of pyogenic arthritis with unclear etiology and potential rodent exposure, <em>Streptobacillus</em> spp., including <em>S. notomytis</em>, should be considered. Comprehensive diagnostics, including 16S rRNA sequencing, are essential for accurate pathogen identification, and careful monitoring for complications like osteomyelitis is crucial during management.</div></div>","PeriodicalId":16103,"journal":{"name":"Journal of Infection and Chemotherapy","volume":"31 8","pages":"Article 102746"},"PeriodicalIF":1.9,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144234343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Pharmacokinetics of ganciclovir for prevention of cytomegalovirus infection in a lung transplant recipient on veno-arterial extracorporeal membrane oxygenation: A case report and literature review","authors":"Yusuke Kojima , Yoshiki Katada , Shunsaku Nakagawa , Keisuke Umemura , Yurie Katsube , Daiki Hira , Masahiro Tsuda , Hiroki Ishimura , Katsuyuki Matsumura , Machiko Hirai , Miki Nagao , Satona Tanaka , Daisuke Nakajima , Hiroshi Date , Tomohiro Terada","doi":"10.1016/j.jiac.2025.102745","DOIUrl":"10.1016/j.jiac.2025.102745","url":null,"abstract":"<div><div>Ganciclovir (GCV) plays an important role in preventing cytomegalovirus (CMV) infection after lung transplantation. Because of the large inter-individual and intra-individual variabilities in GCV pharmacokinetics, it has been suggested that individualized dosages based on blood levels are required. However, GCV pharmacokinetics during veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is unknown. Here, we describe a case in which blood levels of GCV were measured during ECMO after lung transplantation. Additionally, we compared the blood levels of GCV in this case with those of 11 lung transplant recipients who were not on ECMO. A woman in her 40s who underwent deceased-donor bilateral lung transplantation was treated with prolonged VA-ECMO postoperatively. Prophylactic administration of GCV (2.5 mg/kg/12 h) was initiated on postoperative day (POD) 7. The GCV trough concentration during ECMO (PODs 8–28) was 940 ± 854 ng/mL. Thrombocytopenia and renal dysfunction were observed on POD 23. Conversely, 11 adult patients who underwent lung transplantation in the same year as the present patient, but without ECMO, had a GCV trough concentration of 445 ± 263 ng/mL on PODs 8–28. This is the first report of GCV trough concentrations in a patient receiving VA-ECMO after lung transplantation. Compared with lung transplant patients not receiving ECMO, this patient undergoing ECMO exhibited elevated GCV blood trough concentrations, along with acute kidney injury and thrombocytopenia. When GCV is administered during VA-ECMO, therapeutic drug monitoring may be necessary to prevent adverse reactions and account for intra-individual variability.</div></div>","PeriodicalId":16103,"journal":{"name":"Journal of Infection and Chemotherapy","volume":"31 8","pages":"Article 102745"},"PeriodicalIF":1.9,"publicationDate":"2025-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144225617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Comparison of adverse reactions to COVID-19 XBB.1.5 and influenza vaccination in the 2023-24 Japanese influenza season","authors":"Naoki Kawai , Hideyuki Ikematsu , Takuma Bando , Woon Joo Lee , Shinro Matsuura , Maeda Tetsunari , Mariko Echizen , Takashi Kawashima","doi":"10.1016/j.jiac.2025.102728","DOIUrl":"10.1016/j.jiac.2025.102728","url":null,"abstract":"<div><h3>Introduction</h3><div>Adverse reactions to the most recent XBB.1.5 monovalent COVID-19 and seasonal influenza vaccines administered from September to December in 2023 were compared.</div></div><div><h3>Methods</h3><div>Outpatients were administered the COVID-19 and/or influenza vaccine. Patients reported five local and six systemic solicited adverse reactions for seven days through a self-report diary. The data from 217 diaries for the COVID-19 vaccine and 140 diaries for the influenza vaccine were collected and analyzed, including 43 diaries from subjects who received both vaccines and recorded a diary, for a total of 357 diaries from 314 subjects.</div></div><div><h3>Results</h3><div>Among the systemic reactions, fatigue, headache, and myalgia were more frequent with the COVID-19 vaccine (p < 0.001, p < 0.01, p < 0.001, respectively). The local adverse reactions of redness and swelling were significantly more frequent with the influenza vaccine (p < 0.001 and p < 0.05, respectively). For both vaccines, most of the systemic and local reactions were less frequent in subjects 65 years or over than in those under 65. No significant increase in adverse reactions was observed for vaccinations within 14 days compared to those more than 14 days apart or the COVID-19 vaccine alone. Multiple regression analysis also showed that systemic reactions including fatigue, headache, and myalgia, to COVID-19 vaccine, were negatively correlated with age (p < 0.001, p < 0.001 and p = 0.005, respectively).</div></div><div><h3>Conclusions</h3><div>These findings suggest that there are significant differences between the COVID-19 and influenza vaccines in terms of the composition of the adverse reactions and there is a lower incidence of adverse reactions for persons 65 years or older.</div></div>","PeriodicalId":16103,"journal":{"name":"Journal of Infection and Chemotherapy","volume":"31 8","pages":"Article 102728"},"PeriodicalIF":1.9,"publicationDate":"2025-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144208716","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rasha M. Abdel-Hamid , Rasha M. Allam , Lobna Refaat , Hend A. Nooh , Farida M. Mahmoud , Ahmed Bayoumi , Safaa S. Hassan
{"title":"Unraveling mortality risks in pediatric oncology: Exploring bloodstream coinfections and inflammatory biomarkers in COVID-19","authors":"Rasha M. Abdel-Hamid , Rasha M. Allam , Lobna Refaat , Hend A. Nooh , Farida M. Mahmoud , Ahmed Bayoumi , Safaa S. Hassan","doi":"10.1016/j.jiac.2025.102741","DOIUrl":"10.1016/j.jiac.2025.102741","url":null,"abstract":"<div><h3>Background</h3><div>Pediatric oncology patients face heightened mortality rates, primarily due to bacteremia exacerbated by the ongoing COVID-19 pandemic. Given hyperinflammation's role in coronavirus pathogenesis and the importance of inflammatory biomarkers in adults, we aim to explore 60-day mortality predictors in children with cancer, where research remains limited. This study aimed to investigate predictors of mortality in pediatric oncology patients with COVID-19, focusing on bacteremia and inflammatory biomarkers.</div></div><div><h3>Methods</h3><div>Sixty pediatric cancer patients with COVID-19 and 60 with bacteremia (no COVID-19) were included. Bloodstream coinfections were identified, and causative species with antimicrobial sensitivities were characterized. Various inflammatory indices were calculated. Survival analyses identified risk factors for COVID-19 patients’ mortality. Mortality factors in bacteremia patients were examined.</div></div><div><h3>Results</h3><div>The 60-day OS rate of COVID-19 pediatrics was 81.7 %. Worse outcomes were associated with solid tumors, ICU admission, moderate/severe COVID-19, lymphopenia, high NLR, high CLR, and Gram-negative bacteremia (<em>p</em>-values = 0.002, 0.025, 0.042, 0.013, 0.047, 0.052, and 0.025). Multivariate analysis identified solid tumors, high NLR, and high CLR as independent factors for lower OS (<em>p</em>-values = 0.003, 0.046, and 0.046). Bacteremia was revealed in 24 COVID-19 patients (40 %). In patients with bacteremia (n = 84), non-survivors exhibited higher rates of ICU admission, fever, Gram-negative bacteria (GNB), and elevated CRP (<em>p</em>-values = 0.007, 0.038, <0.001, and 0.006), with multivariate analysis identifying GNB and ICU as independent mortality risk factors (<em>p</em>-values = 0.002 and 0.031). <em>Conclusions</em>: NLR and CLR predict mortality in pediatric oncology patients with COVID-19, with solid tumors heightening risk. Infection severity, GNB, and patient condition significantly influence outcomes of bacteremia cancer patients.</div></div>","PeriodicalId":16103,"journal":{"name":"Journal of Infection and Chemotherapy","volume":"31 7","pages":"Article 102741"},"PeriodicalIF":1.9,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144191897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Impact of the COVID-19 pandemic on the regional epidemiology of methicillin-resistant Staphylococcus aureus in the Kumamoto region","authors":"Keiichi Yamamoto , Hideyuki Hayashi , Kanako Mizuta , Rika Fukushima , Kenyu Hashimoto , Hirotomo Nakata , Hitomi Maeda , Tomohiro Sawa , Tatsuya Kawaguchi , Hiroyasu Tsutsuki","doi":"10.1016/j.jiac.2025.102743","DOIUrl":"10.1016/j.jiac.2025.102743","url":null,"abstract":"<div><div>The COVID-19 pandemic caused the collapse of various health systems globally. Several studies have examined the impact of the increase in COVID-19 patients on antimicrobial resistance, but conclusions are controversial. This study aimed to clarify the impact of the COVID-19 pandemic on MRSA trends in the Kumamoto region. We analyzed the detection trends of MRSA using bacterial surveillance data from facilities in the Kumamoto Healthcare-associated Infection Prevention and Control Network from 2017 to 2022. Compared to pre-pandemic data, MRSA detection rates since 2020 have decreased. This was thought to be due to a decrease in the number of bacteriological tests of respiratory specimens, in which MRSA was frequently detected before the pandemic. On the other hand, that of skin and soft tissue specimens were not affected by the pandemic. The MRSA detection rate in these specimens showed a downward trend, suggesting that the increased awareness of infection control measures, including hand hygiene during the pandemic possibly had an impact. We further performed POT method analysis using a clinically isolated MRSA library from Kumamoto University Hospital. The monthly detection rate of the predominant POT type fluctuated from FY2020 to FY2022, and this clonal shift may have contributed to the decline in the MRSA detection rate in the Kumamoto region during the pandemic period. Throughout the pandemic, MRSA clones continued to evolve. Notably, the prevalence of clone 106-247-33, which was dominant in the early phase, may have fluctuated, potentially in relation to variations in the stringency of infection control measures. Therefore, further reductions in MRSA can be expected with maintaining robust implementation of infection control.</div></div>","PeriodicalId":16103,"journal":{"name":"Journal of Infection and Chemotherapy","volume":"31 8","pages":"Article 102743"},"PeriodicalIF":1.9,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144191895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Stability of a blaGES-5-carrying plasmid in a Serratia marcescens nosocomial outbreak","authors":"Shoko Komatsu, Ryohei Nomoto, Noriko Nakanishi","doi":"10.1016/j.jiac.2025.102742","DOIUrl":"10.1016/j.jiac.2025.102742","url":null,"abstract":"<div><div>In 2020, an outbreak of <em>bla</em><sub>GES-5</sub>-carrying plasmid, p2020-O-9, harboring <em>S. marcescens</em> occurred in an intensive care unit in Kobe City, Japan [1]. During the outbreak, strains with and without p2020-O-9 were simultaneously isolated from three patients; hence, we evaluate the stability of p2020-O-9 and its contribution to carbapenem resistance. Growth and transcriptional expression of <em>bla</em><sub>GES-5</sub> were affected by the presence of p2020-O-9 at a meropenem concentration of at least 4 μg/mL. The <em>bla</em><sub>GES-5</sub>-harboring plasmid could be transformed into <em>Escherichia coli</em> via electroporation, but not conjugation. The p2020-O-9 plasmid was highly unstable, and complete loss was observed at the 25th serial passage when antibiotic pressure was withdrawn. Therefore, the <em>bla</em><sub>GES-5</sub>-harboring plasmid p2020-O-9 was unstable and non-conjugative, and contributed to meropenem resistance in a concentration-dependent manner in the previously reported <em>S. marcescens</em> nosocomial outbreak.</div></div>","PeriodicalId":16103,"journal":{"name":"Journal of Infection and Chemotherapy","volume":"31 7","pages":"Article 102742"},"PeriodicalIF":1.9,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144191896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}