Journal of Infection and Chemotherapy最新文献

{"title":"Structured framework for the application of metagenomic next-generation sequencing in the whole-process management of lower respiratory tract infections","authors":"Meihua Zhao ,&nbsp;Xisheng Yu ,&nbsp;Meizeng Zhao ,&nbsp;Guoqing Zhang","doi":"10.1016/j.jiac.2026.102910","DOIUrl":"10.1016/j.jiac.2026.102910","url":null,"abstract":"<div><h3>Objectives</h3><div>This study aims to assess the impact of metagenomic next-generation sequencing (mNGS) on optimizing diagnostic-therapeutic pathways for lower respiratory tract infections (LRTIs).</div></div><div><h3>Methods</h3><div>This retrospective observational study analyzed 42 consecutive LRTI patients at Jiading Branch of Shanghai General Hospital (June 2023–October 2024). Comprehensive clinical data were evaluated including demographic features, laboratory result, radiological findings, mNGS interpretation, treatment modifications, and outcomes.</div></div><div><h3>Results</h3><div>The mNGS detected pathogens in 37/42 patients (88.1 %), despite the fact that 38 patients (90.5 %) had received ineffective empirical antibiotic therapy prior to mNGS testing. More than half the patients (22/42, 52.4 %) had comorbidities and about half the cases were within the normal range in the level of inflammatory biomarker. Pathognomonic CT features suggesting specific pathogens were observed in 33.3 % (14/42) of cases. With regard to the interpretation of mNGS reports combaining the clinical characteristics, the results were consistent with the final diagnosis in 30 (30/42, 71.4 %) patients. Crucially, 92.9 % (39/42) underwent treatment modifications: 66.7 % (28/42) transitioned to targeted/narrower-spectrum antibiotics and 26.2 % (11/42) discontinued antimicrobial therapy following infection exclusion. Patients receiving targeted regimens demonstrated universal clinical improvement with radiological resolution, particularly in complex infections.</div></div><div><h3>Conclusion</h3><div>While mNGS provides robust pathogen detection, its clinical application requires integration with multidimensional patient data. The standardized protocol proposed in this study has the potential to enhances diagnostic efficiency and resource utilization in LRTI management.</div></div>","PeriodicalId":16103,"journal":{"name":"Journal of Infection and Chemotherapy","volume":"32 2","pages":"Article 102910"},"PeriodicalIF":1.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145998288","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":"Clinical and Microbiological Characteristics of macrolide-resistant Bordetella pertussis Infection: A case series in Osaka, Japan (2024–2025)","authors":"Kimihiro Taniguchi ,&nbsp;Takahiro Yamaguchi ,&nbsp;Kenichi Isoda ,&nbsp;Masashi Shiomi ,&nbsp;Yasuhiro Kawasaki ,&nbsp;Kiyoko Amo ,&nbsp;Yuki Wakabayashi ,&nbsp;Ryuji Kawahara ,&nbsp;Masatoshi Nozaki","doi":"10.1016/j.jiac.2026.102916","DOIUrl":"10.1016/j.jiac.2026.102916","url":null,"abstract":"<div><h3>Background</h3><div>Although macrolide antibiotics are an effective first-line treatment for pertussis, the global emergence and spread of macrolide-resistant <em>Bordetella pertussis</em> (MRBP) presents a significant threat to antimicrobial treatment strategies. However, the current status of MRBP in Japan remains unclear due to the lack of a surveillance system. This study aimed to highlight the emergence and clinical impact of MRBP in Osaka, Japan.</div></div><div><h3>Methods</h3><div>We retrospectively reviewed cases of patients with pertussis whose <em>B. pertussis</em> strains were analyzed at the Osaka Institute of Public Health between August 2024 and January 2025. Information on the patients’ clinical characteristics, therapeutic interventions, antimicrobial susceptibility, and molecular analysis of <em>B. pertussis</em> strains was collected. During the study period, eight <em>B. pertussis</em> strains were analyzed.</div></div><div><h3>Results</h3><div>Seven of the eight (87.5 %) <em>B. pertussis</em> strains were macrolide resistant. All of the MRBP strains were highly resistant to macrolide antibiotics and carried the A2047G mutation in domain V of the 23S rRNA gene. Seven of the patients were pediatric; four of whom had not been fully vaccinated due to their young age. One unvaccinated 31-day-old infant experienced clinical and microbiological treatment failure following macrolide administration, resulting in severe hypoxia and lymphocytosis.</div></div><div><h3>Conclusions</h3><div>This descriptive analysis of recent pertussis cases in Osaka identified a high proportion of macrolide-resistant strains among the analyzed cases. Notably, one infant developed severe disease despite macrolide treatment. These findings support the urgent need for nationwide surveillance of macrolide resistance in Japan and the establishment of an appropriate initial antimicrobial strategy for suspected MRBP.</div></div>","PeriodicalId":16103,"journal":{"name":"Journal of Infection and Chemotherapy","volume":"32 2","pages":"Article 102916"},"PeriodicalIF":1.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146078890","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":"Promoting COVID-19 vaccination: Results of a 2024 Japanese survey of outpatient intention to vaccinate","authors":"Takuma Bando,&nbsp;Hideyuki Ikematsu,&nbsp;Kazuya Hamada,&nbsp;Masako Negami,&nbsp;Hiroyuki Fujii,&nbsp;Ken-ichi Doniwa,&nbsp;Naoki Kawai","doi":"10.1016/j.jiac.2026.102911","DOIUrl":"10.1016/j.jiac.2026.102911","url":null,"abstract":"<div><h3>Objectives</h3><div>This study aimed to examine outpatient perceptions of voluntary, routine coronavirus disease (COVID-19) vaccinations scheduled for fall and winter of 2024.</div></div><div><h3>Methods</h3><div>A questionnaire was administered to the patients of five Japanese general medicine clinics.</div></div><div><h3>Results</h3><div>A total of 692 questionnaires were returned. Of the respondents, 38.5 % intended to receive vaccination. The intention to be vaccinated was significantly higher among respondents aged ≥60 years and those with high-risk underlying conditions, and was lower among those with a history of COVID-19. Intention increased as the number of past vaccinations increased. Multivariable logistic regression analysis revealed a significantly lower intention for women than for men. A higher number of past vaccinations was significantly associated with greater intention. The most frequently cited reason for hesitancy was concerns about adverse reactions, particularly among women (44.3 %). Of the respondents, &gt;90 % preferred a vaccination fee of &lt;3000 JPY.</div></div><div><h3>Conclusion</h3><div>To encourage COVID-19 vaccination, it is essential to provide clear information on adverse effects, particularly for women and individuals with fewer prior vaccinations. Reducing the out-of-pocket cost of vaccination to 3000 to 5000 JPY or less through public subsidies would likely improve coverage.</div></div>","PeriodicalId":16103,"journal":{"name":"Journal of Infection and Chemotherapy","volume":"32 2","pages":"Article 102911"},"PeriodicalIF":1.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146018758","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":"Pneumonia in frail older adults: from diagnosis to optimized management","authors":"Kosaku Komiya ,&nbsp;Yuki Yoshimatsu ,&nbsp;Akihiko Hagiwara ,&nbsp;Ryohei Kudoh ,&nbsp;Hisayuki Shuto ,&nbsp;Izumi Yamatani ,&nbsp;Akihiko Goto","doi":"10.1016/j.jiac.2026.102914","DOIUrl":"10.1016/j.jiac.2026.102914","url":null,"abstract":"<div><div>In the context of global population aging, pneumonia in older adults has become increasingly prevalent; frequently fatal; and remains challenging to diagnose, treat, and manage in alignment with patient goals. This narrative review synthesized contemporary evidence on pneumonia, particularly aspiration pneumonia, in older adults, integrating perspectives from diagnosis, antimicrobial management, prognosis, prevention, and end-of-life care. In this population, pneumonia often presents with atypical or nonspecific manifestations. Aspiration events are rarely directly observed, and current diagnostic definitions remain imprecise. Outcomes are predominantly driven by host-related factors, including frailty, dysphagia, multimorbidity, functional decline, and malnutrition, and conventional severity scores perform sub-optimally. Evidence from large observational studies indicated that early broad-spectrum or anaerobic-covering antibiotics provided limited survival benefit and may contribute to antimicrobial resistance, underscoring the importance of distinguishing colonization from true infection and adopting a stewardship-oriented approach. Preventive strategies include oral hygiene, postural and dietary modification, judicious medication review, and vaccination against major respiratory pathogens. In individuals with advanced frailty or recurrent pneumonia, multidisciplinary, ethically grounded, and shared decision-making on oral intake, eating and drinking with acknowledged risk, clinically assisted nutrition and hydration, and the role of antibiotics is required. Overall, pneumonia in older adults, particularly aspiration pneumonia, should be regarded as both an infectious disease and a clinical phenotype of age-associated vulnerability, which warrant a multidimensional approach that integrates geriatric assessment, antimicrobial stewardship, targeted prevention, and end-of-life care planning.</div></div>","PeriodicalId":16103,"journal":{"name":"Journal of Infection and Chemotherapy","volume":"32 2","pages":"Article 102914"},"PeriodicalIF":1.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146044197","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":"Severe gastroenteritis caused by Vibrio cholerae serogroup O24 in an immunocompromised patient: A case report","authors":"Tomoko Azuma ,&nbsp;Yoshinori Takahashi ,&nbsp;Megumi Oshima ,&nbsp;Megumi Ikeda ,&nbsp;Daiki Hayasi ,&nbsp;Hatsumi Otani ,&nbsp;Akiko Maekawa ,&nbsp;Hiroyasu Oe ,&nbsp;Aya Noguchi ,&nbsp;Mika Mori ,&nbsp;Hajime Kanamori","doi":"10.1016/j.jiac.2026.102906","DOIUrl":"10.1016/j.jiac.2026.102906","url":null,"abstract":"<div><div>Non-O1 and non-O139 <em>Vibrio cholerae</em> (NOVC) strains rarely harbor the cholera toxin gene and are typically associated with mild, self-limiting gastroenteritis. However, an increasing number of reports in recent years have described severe gastroenteritis or extraintestinal infections with fatal outcomes, particularly in immunocompromised individuals, such as those with underlying conditions including cirrhosis. Here, we describe a case of severe gastroenteritis caused by <em>V. cholerae</em> serogroup O24, following the consumption of seafood during prolong prednisolone treatment for systemic lupus erythematosus. Stool culture upon admission yielded yellow colonies on thiosulfate-citrate-bile salt-sucrose agar, and Gram staining of the colonies revealed Gram-negative, curved, comma-shaped rods, suggestive of <em>Vibrio</em> species. Although matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) yielded low-confidence identifications, suggesting either <em>Vibrio mimicus</em> or <em>Vibrio albensis</em>, the isolate was ultimately identified as NOVC based on its biochemical characteristics and salt tolerance. Subsequent genetic analysis confirmed the isolate as <em>V. cholerae</em> serogroup O24, a strain not included in the MALDI-TOF MS identification database. This case underscores the diagnostic value of conventional methods, such as biochemical profiling, in identifying <em>V. cholerae</em> strains not detectable by current mass spectrometry-based systems.</div></div>","PeriodicalId":16103,"journal":{"name":"Journal of Infection and Chemotherapy","volume":"32 2","pages":"Article 102906"},"PeriodicalIF":1.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145928990","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":"Diagnostic utility of urinalysis parameters in predicting urine culture positivity: A gender-stratified evaluation","authors":"Fatih Çubuk ,&nbsp;Caner Öksüz ,&nbsp;Murtaza Öz","doi":"10.1016/j.jiac.2026.102904","DOIUrl":"10.1016/j.jiac.2026.102904","url":null,"abstract":"<div><h3>Objective</h3><div>A substantial proportion of urine cultures in patients with suspected urinary tract infections (UTIs) yield negative results. This study aimed to evaluate whether parameters from automated urinalysis could predict the likelihood of significant bacterial growth, thereby aiding in reducing unnecessary cultures.</div></div><div><h3>Methods</h3><div>A total of 696 patients (402 females, 294 males) undergoing urinalysis with the FUS-200 automated analyzer were evaluated. Urine cultures were processed using the BD Phoenix 100 system. Demographic data and urinalysis parameters were compared according to culture results.</div></div><div><h3>Results</h3><div>Among culture-negative patients, females were younger (median age: 45 vs. 58 years, p = 0.000) and had significantly higher leukocyte, erythrocyte, and bacterial counts (p = 0.000). In culture-positive cases, females were younger than males (55 vs. 72.5 years, p = 0.000), though they had lower leukocyte counts (p = 0.029). Gram-negative infections were associated with significantly higher leukocyte and bacterial counts compared to gram-positive infections (p &lt; 0.05), along with increased nitrite and leukocyte esterase positivity. ROC analysis identified optimal cut-off values for predicting significant culture growth: leukocyte count ≥16.5 (sensitivity, 79.5 %; specificity, 79.9 %) and bacterial count ≥2.5 (sensitivity, 77.6 %; specificity, 79.3 %). Cut-off values were higher in females (leukocytes: 23.5, bacteria: 5.5) than in males (leukocytes: 11.5, bacteria: 0.5).</div></div><div><h3>Conclusion</h3><div>The practical utility of the defined normal range values for urinary leukocyte count is limited. The predictive power of urinalysis parameters for culture results is affected by patient gender. For predicting significant bacterial growth in males, we recommend leukocyte and bacteria cut-off values of 11.5/HPF and 0.5/HPF, respectively (with &gt;85 % sensitivity and specificity). In females, leukocyte and bacterial counts in urine provide poor predictive value for culture positivity.</div></div>","PeriodicalId":16103,"journal":{"name":"Journal of Infection and Chemotherapy","volume":"32 2","pages":"Article 102904"},"PeriodicalIF":1.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145903896","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":"In vitro activity of cefiderocol against carbapenem-resistant Gram-negative pathogens in Japan","authors":"Kenjiro Matsui ,&nbsp;Aki Sakurai ,&nbsp;Yasufumi Matsumura ,&nbsp;Takuya Hosoda ,&nbsp;Masahiro Suzuki ,&nbsp;Sho Saito ,&nbsp;Ryota Hase ,&nbsp;Hideaki Kato ,&nbsp;Takehiro Hashimoto ,&nbsp;Takashi Matono ,&nbsp;Naoya Itoh ,&nbsp;Momoko Mawatari ,&nbsp;Kohei Uemura ,&nbsp;Kayoko Hayakawa ,&nbsp;Hiroyasu Ito ,&nbsp;Yohei Doi","doi":"10.1016/j.jiac.2026.102905","DOIUrl":"10.1016/j.jiac.2026.102905","url":null,"abstract":"<div><h3>Introduction</h3><div>Carbapenem-resistant Gram-negative bacteria (CRGNB) pose a major clinical threat. This study evaluated the <em>in vitro</em> activity of cefiderocol and other recently approved β-lactam/β-lactamase inhibitor combinations against major CRGNB.</div></div><div><h3>Materials and methods</h3><div>A total of 292 CRGNB clinical isolates were analyzed, comprising 146 Enterobacterales, 106 <em>Pseudomonas aeruginosa</em>, and 40 <em>Stenotrophomonas maltophilia</em>, all collected from hospitals across Japan. Antimicrobial susceptibility testing was performed by broth microdilution (BMD). Disk diffusion testing was also conducted for cefiderocol, and categorical agreement with BMD was assessed. Whole-genome sequencing (WGS) was used for species confirmation and characterization of resistance determinants.</div></div><div><h3>Results</h3><div>Carbapenemase producers accounted for 64.4 % of Enterobacterales (94/146) and 8.5 % of <em>P. aeruginosa</em> (9/106), with metallo-β-lactamase (MBL) producers comprising 92.6 % (87/94) and 77.8 % (7/9), respectively. Based on CLSI breakpoints, 94.5 % (276/292) of isolates were susceptible to cefiderocol, including 91.8 % of Enterobacterales, 99.1 % of <em>P. aeruginosa</em>, and 92.5 % of <em>S. maltophilia</em>. Ceftolozane-tazobactam, ceftazidime-avibactam, and imipenem-relebactam were active against 12.3 %, 44.5 % and 45.9 % of Enterobacterales, and 89.6 %, 86.8 % and 72.6 % of <em>P. aeruginosa</em>, respectively. Categorical agreement between cefiderocol disk diffusion and BMD exceeded 92 % across all groups, although very major errors occurred in Enterobacterales (n = 2) and <em>S. maltophilia</em> (n = 3). Cefiderocol-non-susceptible Enterobacterales isolates frequently harbored carbapenemase and extended-spectrum β-lactamase (ESBL) genes, together with mutations in <em>ftsI</em> (encoding PBP3), <em>ompK35</em>, or siderophore receptor genes (<em>cirA, tonB</em>).</div></div><div><h3>Discussion</h3><div>Cefiderocol showed potent <em>in vitro</em> activity against CRGNB in Japan, including MBL producers. Disk diffusion correlated well with BMD results; however, confirmatory BMD testing should be considered when resistance is clinically suspected.</div></div>","PeriodicalId":16103,"journal":{"name":"Journal of Infection and Chemotherapy","volume":"32 2","pages":"Article 102905"},"PeriodicalIF":1.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145933602","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":"Evaluation of Japan-specific cefiderocol susceptibility testing methods in multidrug-resistant gram-negative isolates from Japan and Bangladesh","authors":"Takashi Okanda ,&nbsp;Niinyo Nakajima ,&nbsp;Takuro Koshikawa ,&nbsp;Tadatomo Oyanagi ,&nbsp;Tomonori Takano ,&nbsp;Tetsuo Yamaguchi ,&nbsp;Hiroyuki Kunishima ,&nbsp;Mitsuo Kaku ,&nbsp;Hiromu Takemura","doi":"10.1016/j.jiac.2026.102903","DOIUrl":"10.1016/j.jiac.2026.102903","url":null,"abstract":"<div><h3>Background</h3><div>Cefiderocol (CFDC) exhibits potent in vitro activity against multidrug-resistant Gram-negative bacilli (MDR-GNB), yet standardized susceptibility testing remains technically demanding. This study evaluated the reproducibility and categorical agreement (CA) of broth microdilution (BMD), MIC dry plate (DP), and disk diffusion (DD) using MDR-GNB from Japan and Bangladesh. To our knowledge, this is the first systematic assessment of Japan-specific commercial platforms for CFDC testing.</div></div><div><h3>Methods</h3><div>A total of 452 MDR-GNB isolates, including 272 Enterobacterales and 180 non-fermenters (<em>Pseudomonas aeruginosa</em>, <em>Acinetobacter baumannii</em>, <em>Stenotrophomonas maltophilia</em>), were tested using BMD and two commercial platforms. Reproducibility was assessed in triplicate, and essential agreement, CA, and error rates were determined with BMD as the reference.</div></div><div><h3>Results</h3><div>BMD demonstrated &gt;90 % reproducibility across species. DP and DD showed reduced reproducibility and agreement for NDM-producing Enterobacterales, with CA of 54 % for DP and 63 % for DD. Most discrepancies were minor errors. Trailing effects and visual artifacts contributed to elevated MICs, particularly in DP.</div></div><div><h3>Conclusions</h3><div>The performance of simplified CFDC susceptibility methods varies by species and resistance mechanism, with notable limitations for NDM producers. While DP and DD remain practical tools for routine laboratories, their use requires caution. Parallel DP–DD testing does not replace BMD but can help identify discrepant results requiring confirmation, particularly for NDM-producing isolates.</div></div>","PeriodicalId":16103,"journal":{"name":"Journal of Infection and Chemotherapy","volume":"32 2","pages":"Article 102903"},"PeriodicalIF":1.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145952232","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":"Microbiologic clearance in macrolide-resistant Bordetella pertussis: An infant treated with sulfamethoxazole-trimethoprim — A case timeline","authors":"Yu Kuramochi ,&nbsp;Meiwa Shibata ,&nbsp;Mikako Morinaga ,&nbsp;Tomoyuki Tame ,&nbsp;Kazue Kinoshita ,&nbsp;Osamu Saito ,&nbsp;Yuho Horikoshi","doi":"10.1016/j.jiac.2026.102907","DOIUrl":"10.1016/j.jiac.2026.102907","url":null,"abstract":"<div><div>Amid a large-scale resurgence of pertussis in Japan in 2025, concern is growing about the spread of macrolide-resistant <em>Bordetella pertussis</em> (MRBP)—prevalent in China—posing a clinical challenge, particularly in infants. We describe a term 6-week-old unvaccinated infant with life-threatening MRBP. Diagnosis was confirmed by culture and multiplex PCR. The isolate harbored the 23S rRNA A2047G mutation. Daily microbiology (Gram stain, culture, quantitative PCR) was performed on nasopharyngeal swabs and lower-airway aspirates. The infant received empiric azithromycin and a 14-day course of sulfamethoxazole–trimethoprim (SMX-TMP) and recovered without sequelae. Nasopharyngeal cultures became negative by Day 2 of SMX-TMP therapy, and lower-airway aspirate cultures by Day 3. Nasopharyngeal quantitative PCR was below the detection limit by Day 7. Lower-airway quantitative PCR declined through Day 7, and sampling ceased after extubation. These observations suggest that bacteriologic clearance with SMX-TMP may occur on a time frame similar to that used to discontinue precautions for macrolide-susceptible disease, commonly five days after starting effective therapy. During the current resurgence in Japan, transmission appears concentrated among school-aged children, whereas the national vaccination program targets only those under two years of age. Introducing booster doses at 5–6 and 11–12 years may help reduce school-based transmission. In addition, maternal booster vaccination during pregnancy could protect young infants through the transplacental transfer of maternal pertussis antibodies.</div></div>","PeriodicalId":16103,"journal":{"name":"Journal of Infection and Chemotherapy","volume":"32 2","pages":"Article 102907"},"PeriodicalIF":1.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145952276","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":"Orbital cellulitis with emm1-type M1UK sublineage group A Streptococcus detected in a blood culture: a case report","authors":"Aya Tateishi ,&nbsp;Takeru Kanazawa ,&nbsp;Kazuhiko Matsuhashi ,&nbsp;Ryo Karato ,&nbsp;Yoshifusa Abe ,&nbsp;Ayumi Tada ,&nbsp;Yuho Horikoshi","doi":"10.1016/j.jiac.2026.102913","DOIUrl":"10.1016/j.jiac.2026.102913","url":null,"abstract":"<div><div>Invasive group A streptococcal infection (iGAS) increases in Europe and it causes skin and soft-tissue infection, including orbital cellulitis. In this study, we report a case of a 7-year-old girl with orbital cellulitis and invasive <em>emm</em>1-type M1_UK sublineage group A <em>Streptococcus</em> (GAS) detected in a blood culture. The patient was initially treated with a combination of cefotaxime (CTX) and clindamycin (CLDM). We changed antibiotics from CTX to ampicillin after susceptibility results were known. After discharge, oral clavulanic acid/amoxicillin was continued as an oral medication, and antibiotics were administered for a total of 21 days. The bacterium was isolated from a blood culture and identified as an <em>emm</em>1-type M1_UK sublineage GAS. This case is unusual in that it involved bloodstream infection in a pediatric orbital cellulitis, and M1_UK's highly toxin-producing and highly transmissible may have been implicated. In rapidly exacerbating orbital cellulitis, iGAS infection should be considered.</div></div>","PeriodicalId":16103,"journal":{"name":"Journal of Infection and Chemotherapy","volume":"32 2","pages":"Article 102913"},"PeriodicalIF":1.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146044175","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}