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BACKGROUND: Coronavirus disease 2019 (COVID-19)-associated pulmonary aspergillosis (CAPA) is one of the noticeable complications of COVID-19 and its incidence varies widely. In Japan, research on the incidence, risk factors and mortality associated with CAPA is limited. OBJECTIVES: This study aimed to explore the incidence and potential risk factors for CAPA in patients with severe or critical COVID-19 and evaluate the relationship between CAPA and mortality of patients with severe or critical COVID-19. METHODS: We investigated the incidence of CAPA in patients with severe and critical COVID-19 using administrative claims data from acute care hospitals in Japan. We employed multivariable regression models to explore potential risk factors for CAPA and their contribution to mortality in patients with severe and critical COVID-19. RESULTS: The incidence of CAPA was 0.4%-2.7% in 33,136 patients with severe to critical COVID-19. Age, male sex, chronic lung disease, steroids, immunosuppressants, intensive care unit admission, blood transfusion and dialysis were potential risk factors for CAPA in patients with severe to critical COVID-19. CAPA was an independent factor associated with mortality. CONCLUSIONS: CAPA is a serious complication in patients with severe and critical COVID-19 and may increase mortality.
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COVID-19 , Aspergilose Pulmonar , Humanos , Masculino , COVID-19/complicações , COVID-19/epidemiologia , COVID-19/mortalidade , Feminino , Fatores de Risco , Pessoa de Meia-Idade , Idoso , Japão/epidemiologia , Incidência , Adulto , Aspergilose Pulmonar/epidemiologia , Aspergilose Pulmonar/complicações , SARS-CoV-2 , Idoso de 80 Anos ou mais , Adulto JovemRESUMO
BACKGROUND: Human cytomegalovirus (HCMV) infection occurs in immunosuppressed individuals and is known to increase mortality. Patients with coronavirus disease 2019 (COVID-19) are often treated with steroids, require intensive care unit (ICU) treatment, and may therefore be at risk for HCMV infection. However, which factors predispose severely ill patients with COVID-19 to HCMV infection and the prognostic value of such infections remain largely unexplored. This study aimed to examine the incidence and potential risk factors of HCMV infection in patients with severe or critical COVID-19 and evaluate the relationship between HCMV infection and mortality. METHODS AND FINDINGS: We used administrative claims data from advanced treatment hospitals in Japan to identify and analyze patients with severe or critical COVID-19. We explored potential risk factors for HCMV infection using multivariable regression models and its contribution to mortality in patients with COVID-19. Overall, 33,151 patients who progressed to severe or critical COVID-19 illness were identified. The incidence of HCMV infection was 0.3-1.7 % depending on the definition of HCMV infection. Steroids, immunosuppressants, ICU admission, and blood transfusion were strongly associated with HCMV infection. Furthermore, HCMV infection was associated with patient mortality independent of the observed risk factors for death. CONCLUSIONS: HCMV infection is a notable complication in patients with severe or critical COVID-19 who are admitted to the ICU or receive steroids, immunosuppressants, and blood transfusion and can significantly increase mortality risk.
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INTRODUCTION: Obesity is a risk factor for aggravation of and mortality from coronavirus disease 2019 (COVID-19). We aimed to investigate the relationship between COVID-19 and Body Mass Index (BMI) in the Japanese population. METHODS: We used administrative claims data from an advanced treatment hospital in Japan and extracted data from patients hospitalized for COVID-19. The exposure variable was BMI measured at the time of admission, and the study outcomes were progression to critical illness and death. Analyses were performed for each age group. RESULTS: Overall, 58,944 patients met the inclusion criteria. The risk of critical illness increased monotonically with higher BMI. In contrast, the relationship between BMI and mortality follows a J-shaped curve; being underweight and obese are risk factors for mortality. When stratified by age, similar trends were observed for both critical illness and mortality. CONCLUSION: A higher BMI is a risk factor for the progression of COVID-19 severity, whereas both lower and higher BMIs are risk factors for mortality in the Japanese population.
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To evaluate the antibody response following the initial four doses of mRNA vaccines (BNT162b2 or mRNA-1273) in SARS-CoV-2-naïve healthy adults and investigate factors influencing antibody titer increases, this prospective cohort study was conducted in Japan from March 2021. The study included participants who received either the 1st and 2nd doses (n = 467), 3rd dose (n = 157), or 4th dose (n = 89). Blood samples were collected before and up to 6 months after each dose, and anti-receptor-binding domain antibody levels were measured. Multivariate analysis (usin multiple linear regression or linear mixed models) revealed several factors significantly associated with higher post-vaccination antibody levels, including mRNA-1273 vaccine (after the 1st and 2nd dose), male gender (after the 3rd and 4th doses), younger age (after the 1st and 2nd dose), non-smoking status (after the 2nd dose), non-use of immunosuppressive agents (after the 1st dose), higher pre-vaccination antibody titers (after the 2nd, 3rd, and 4th doses), and higher post-vaccination fever (after the 2nd and 4th doses). Furthermore, longer intervals since the last dose were significantly associated with higher antibody levels after the 3rd and 4th doses. These findings provide valuable insights for optimizing vaccination strategies.
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Vacina de mRNA-1273 contra 2019-nCoV , COVID-19 , Adulto , Masculino , Humanos , SARS-CoV-2 , Vacina BNT162 , Vacinas contra COVID-19 , Estudos Prospectivos , COVID-19/prevenção & controle , Anticorpos , Febre , RNA Mensageiro , Anticorpos Antivirais , VacinaçãoRESUMO
High photovoltaic performance and light stability are required for the practical outdoor use of lead-halide perovskite solar cells. To improve the light stability of perovskite solar cells, it is effective to introduce a self-assembled monolayer (SAM) between the carrier transport layer and the perovskite layer. Several alternative approaches in their molecular design and combination with multiple SAMs support high photovoltaic conversion efficiency (PCE). Herein, we report a new structure for improving both PCE and light stability, in which the surface of an electron transport layer (ETL) was modified by combining a fullerene-functionalized self-assembled monolayer (C60SAM) and a suitable gap-filling self-assembled monolayer (GFSAM). Small-sized GFSAMs can enter the gap space of the C60SAM and terminate the unterminated sites on the ETL surface. The best GFSAM in this study was formed using an isonicotinic acid solution. After a light stability test for 68 h at 50 °C under 1 sun illumination, the best cell with C60SAM and GFSAM showed a PCE of 18.68% with a retention rate of over 99%. Moreover, following outdoor exposure for six months, the cells with C60SAM and GFSAM exhibited almost unchanged PCE. From the valence band spectra of the ETLs obtained using hard X-ray photoelectron spectroscopy, we confirmed a decrease in the offset at the ETL/perovskite interface owing to the additional GFSAM treatment on the C60SAM-modified ETL surface. Time-resolved microwave conductivity measurements demonstrated that the additional GFSAM improved electron extraction at the C60SAM-modified ETL/perovskite interface.
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ABSTRACTExtended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE) bacteremia can have poor clinical outcomes. Thus, determining the predictors of mortality from ESBL-PE bacteremia is very important. The present systematic review and meta-analysis aimed to evaluate studies to determine predictors associated with ESBL-PE bacteremia mortality. We searched PubMed and Cochrane Library databases for all relevant publications from January 2000 to August 2022. The outcome measure was mortality rate. In this systematic review of 22 observational studies, 4607 patients with ESBL-PE bacteremia were evaluated, of whom 976 (21.2%) died. The meta-analysis showed that prior antimicrobial therapy (RR, 2.89; 95% CI, 1.22-6.85), neutropenia (RR, 5.58; 95% CI, 2.03-15.35), nosocomial infection (RR, 2.46; 95% CI, 1.22-4.95), rapidly fatal underlying disease (RR, 4.21; 95% CI, 2.19-8.08), respiratory tract infection (RR, 2.12; 95% CI, 1.33-3.36), Pitt bacteremia score (PBS) (per1) (RR, 1.35; 95% CI, 1.18-1.53), PBS ≥ 4 (RR, 4.02; 95% CI, 2.77-5.85), severe sepsis (RR, 11.74; 95% CI, 4.68-29.43), and severe sepsis or septic shock (RR, 4.19; 95% CI, 2.83-6.18) were found to be mortality predictors. Moreover, urinary tract infection (RR, 0.15; 95% CI, 0.04-0.57) and appropriate empirical therapy (RR, 0.39; 95% CI, 0.18-0.82) were found to be a protective factor against mortality. Patients with ESBL-PE bacteremia who have the aforementioned require prudent management for improved outcomes. This research will lead to better management and improvement of clinical outcomes of patients with bacteremia caused by ESBL-PE.
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Bacteriemia , Infecções por Enterobacteriaceae , Sepse , Humanos , Infecções por Enterobacteriaceae/tratamento farmacológico , Enterobacteriaceae/genética , Bacteriemia/tratamento farmacológico , beta-Lactamases/genética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Estudos Retrospectivos , Resultado do TratamentoRESUMO
There exists decades-old evidence that some mycobacteria, including Mycobacterium avium and Mycobacterium smegmatis, produce hydrazidase, an enzyme that can hydrolyze the first-line antitubercular agent isoniazid. Despite its importance as a potential resistance factor, no studies have attempted to reveal its identity. In this study, we aimed to isolate and identify M. smegmatis hydrazidase, characterize it, and evaluate its impact on isoniazid resistance. We determined the optimal condition under which M. smegmatis produced the highest amount of hydrazidase, purified the enzyme by column chromatography, and identified it by peptide mass fingerprinting. It was revealed to be PzaA, an enzyme known as pyrazinamidase/nicotinamidase whose physiological role remains unknown. The kinetic constants suggested that this amidase with broad substrate specificity prefers amides to hydrazides as a substrate. Notably, of the five tested compounds, including amides, only isoniazid served as an efficient inducer of pzaA transcription, as revealed by quantitative reverse transcription PCR. Moreover, high expression of PzaA was confirmed to be beneficial for the survival and growth of M. smegmatis in the presence of isoniazid. Thus, our findings suggest a possible role for PzaA, and other hydrazidases yet to be identified, as an intrinsic isoniazid resistance factor of mycobacteria.
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Mycobacterium tuberculosis , Mycobacterium , Isoniazida/farmacologia , Antituberculosos/farmacologia , Mycobacterium smegmatis , AmidasRESUMO
INTRODUCTION: Genetic testing is gaining increasing importance as a part of antimicrobial stewardship (AS). Rapid identification and determination of methicillin susceptibility using the Xpert MRSA/SA BC assay can improve the management of Staphylococcus aureus bacteremia (SAB) and reduce inappropriate antibiotic use. However, few reports have described the effectiveness of this approach. METHODS: The present study aimed to assess the influence of AS using the Xpert MRSA/SA BC assay. Cases were classified into the pre-intervention group (n = 98 patients), in which SAB was identified by traditional culture (November 2017 to November 2019), and the post-intervention group (n = 97 patients), in which the Xpert MRSA/SA BC assay was performed when necessary (December 2019 to December 2021). RESULTS: Patient characteristics, prognosis, duration of antimicrobial use, and length of hospital stay were compared between the groups. The Xpert assay was performed in 66 patients in the post-intervention group (68.0%). The two groups showed no significant differences in severity and mortality. The rate of cases treated with anti-MRSA agents reduced following the intervention (65.3% vs. 40.4%, p = 0.008). The number of cases involving definitive therapy within 24 h was higher in the post-intervention group (9.2% vs. 24.7%, p = 0.007). The hospitalization rate at >60 days was lower in Xpert implementation cases among MRSA bacteremia cases (28.6% vs. 0%, p = 0.01). CONCLUSIONS: Thus, the Xpert MRSA/SA BC assay has potential as an AS tool, especially for early definitive treatment to SAB and reduction of long-term hospitalization in MRSA bacteremia cases.
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Gestão de Antimicrobianos , Bacteriemia , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Humanos , Centros de Atenção Terciária , Japão , Staphylococcus aureus Resistente à Meticilina/genética , Bacteriemia/diagnóstico , Bacteriemia/tratamento farmacológico , Antibacterianos/uso terapêutico , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/tratamento farmacológicoRESUMO
BACKGROUND: Klebsiella pneumoniae strains pose a significant threat to public health. Currently, it is inconclusive whether hypermucoviscous K. pneumoniae (hmKp; semi-quantitatively defined by a positive 'string test') bacteraemia is clinically more severe than non-hmKp bacteraemia. Hence, this systematic review and meta-analysis was conducted with the aim of drawing some conclusions on hypermucoviscosity and bacteraemia. METHODS: PubMed and Web of Science databases were searched for all relevant publications from January 2000 to March 2022. The outcome measures were mortality rate and abscess formation. RESULTS: Fourteen observational studies were included in this systematic review, comprising a total of 3092 patients with K. pneumoniae bacteraemia, including 746 (24.1%) patients with hmKp strains. The meta-analysis showed that hmKp bacteraemia did not account for a significant increase in the incidence of all-cause mortality compared with non-hmKp bacteraemia [pooled hazard ratio 1.30, 95% confidence interval (CI) 0.79-2.12; P=0.30]. However, hmKp bacteraemia was associated with a significant increase in the incidence of abscess formation compared with non-hmKp bacteraemia (pooled odds ratio 7.74, 95% CI 4.96-12.06; P<0.00001). CONCLUSIONS: Although mortality may not be dependent on the causative agent, this review reaffirms the importance of the string test to detect hmKp. There is a need for prudent management, especially for patients with hmKp, that should include investigations for liver abscess and/or metastatic spread, and measures for early and proper source control as this can improve the prognosis.
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Bacteriemia , Infecções por Klebsiella , Abscesso Hepático , Humanos , Klebsiella pneumoniae , Prognóstico , Bacteriemia/epidemiologia , Infecções por Klebsiella/epidemiologiaRESUMO
The multidrug-resistant pathogen Candida auris is characterized by its aggregation under certain conditions, which affects its biofilm formation, drug susceptibility, and pathogenicity. Although the innate tendency to aggregate depends on the strain, the mechanism regulating C. auris aggregation remains unclear. We found that the culture supernatant from one of the 95 Actinomyces strains isolated from a deep-sea environment (IMAs2016D-66) inhibited C. auris aggregation. The cells grown in the presence of IMAs2016D-66 exhibited reduced hydrophobicity, biofilm formation, and enhanced proteolytic activity. In addition, the efflux pump activity of the fluconazole-resistant C. auris strain LSEM 3673 was stimulated by IMAs2016D-66, whereas no significant change was observed in the fluconazole-susceptible strain LSEM 0643. As the relationship between aggregative tendency and virulence in C. auris is still unclear, IMAs2016D-66 can serve as a tool for investigating regulatory mechanisms of phenotype switching and virulence expression of C. auris. Understanding of phenotype switching may help us not only to understand the pathogenicity of C. auris, but also to design new drugs that target the molecules regulating virulence factors.
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Actinobacteria , Virulência , Candida auris , Fluconazol , BiofilmesRESUMO
Clostridium ramosum is one of the obligate anaerobes that constitute the intestinal microbiota, and one of the rare Clostridia. With Clostridium ramosum, very few data have been reported to investigate antimicrobial susceptibility for clinical isolates that have caused bacteremia. Here, we report two cases of Clostridium ramosum bacteremia. The first case was a 54-year-old Japanese man with taking 20mg hydrocortisone for hypopituitarism. He presented to the emergency department for an unknown cause cardiopulmonary arrest. At the hospital day 36, he had fever and a drop in blood pressure. Abdomen computed tomography (CT) revealed free air around the ascending colon, we diagnosed with intestinal perforation, and peritonitis. Blood culture revealed Clostridium ramosum. We administered conservative management by 6-week of antibiotic treatment. The second case was a 78-year-old Japanese man with no significant medical history. He was referred to our hospital with fever and abdominal pain. Abdomen CT revealed perforated appendicitis, and blood cultures revealed Clostridium ramosum. We performed emergency surgery, and administered one-week course of antibiotic treatment. This report demonstrates two cases of Clostridium ramosum bacteremia with intestinal perforation, and the antimicrobial susceptibility of each clinical strain. For the future, it is necessary to accumulate data on the susceptibility of clinical isolates in order to find an appropriate treatment.
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Anti-Infecciosos , Bacteriemia , Perfuração Intestinal , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Perfuração Intestinal/diagnóstico , Bacteriemia/diagnóstico , Bacteriemia/tratamento farmacológico , Antibacterianos/farmacologia , Antibacterianos/uso terapêuticoRESUMO
OBJECTIVES: In hypervirulent Klebsiella pneumoniae (hvKP), the hypermucoviscous capsule is known to be a major virulence determinant. We previously discovered that rifampicin (RFP), a bactericidal drug that binds to and inhibits the ß subunit of RNA polymerase (RpoB), elicits anti-mucoviscous activity against hvKP by suppressing rmpA, a regulator of capsule production. Here, we aimed to determine whether RFP exerts this effect at sub-growth-inhibitory concentrations via its binding to RpoB. METHODS: Five spontaneous RFP-resistant mutants (R1-R5) were prepared from an hvKP clinical isolate and subjected to whole genome sequencing and mucoviscosity analyses. Subsequently, a two-step allelic exchange procedure was used to create a rpoB mutant R6 and revertants with wild-type rpoB from R1-R5 (named R1'-R5'). Transcription levels of rmpA and the capsular polysaccharide polymerase gene magA and capsule thickness of R1-R5 and R1'-R5' grown without or with RFP were evaluated by quantitative reverse transcription polymerase chain reaction and microscopic observation using India ink staining. RESULTS: R1-R5 all had non-synonymous point mutations in rpoB and were highly resistant to the bactericidal effects and anti-mucoviscous activity of RFP. While the properties of R6 were similar to those of R1-R5, the responses of R1'-R5' to RFP were identical to those of the wild type. rmpA and magA transcription levels and capsule thickness correlated well with the mucoviscosity levels. CONCLUSIONS: RFP exerts anti-mucoviscous activity by binding to RpoB. The mechanism of how this causes rmpA suppression remains to be explored.
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Klebsiella pneumoniae , Rifampina , Rifampina/farmacologia , Fatores de Virulência/genética , Antibacterianos/farmacologia , RNA Polimerases Dirigidas por DNA/genéticaRESUMO
OBJECTIVE: Most non-tuberculous mycobacteria exhibit intrinsic resistance against the anti-tuberculosis drug isoniazid (INH). We previously found that a pyrazinamidase/nicotinamidase of Mycobacterium smegmatis, named PzaA, has an enzymatic activity to hydrolyze INH, which may contribute to intrinsic resistance. Furthermore, PzaA expression is strongly induced by INH under nitrogen-depleted conditions, although the precise mechanism of this phenomenon remains unclear. Here, we aimed to reveal the mechanism underlying the INH-dependent induction of PzaA using a transcriptomic approach. METHODS: RNA sequencing was performed to identify INH-inducible genes other than pzaA. 5' rapid amplification of cDNA ends analysis was employed to identify the transcription start sites of INH-induced transcription units. The function of a LuxR-like regulator gene (MSMEI_1050) found within the gene cluster containing pzaA was confirmed by gene deletion and complementation experiments involving INH hydrolysis assay and quantitative reverse transcription PCR. RESULTS: RNA sequencing revealed 23 genes that INH strongly induced under conditions of nitrogen depletion, 17 of which were in a gene cluster containing pzaA. This cluster comprised at least three transcription units, including a non-INH-inducible monocistronic unit containing MSMEI_1050. Deletion of this gene deprived M. smegmatis of the ability to respond to INH, and complementation restored this ability. CONCLUSIONS: MSMEI_1050 plays a key role in INH-dependent gene regulation. The precise mechanism of action is to be determined in future studies.
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Antituberculosos , Isoniazida , Mycobacterium tuberculosis , Antituberculosos/farmacologia , Proteínas de Bactérias/genética , Sequência de Bases , Isoniazida/farmacologia , Mycobacterium smegmatis/genética , Mycobacterium tuberculosis/genética , Transativadores/genéticaRESUMO
BACKGROUND: Although several assays are used to measure anti-receptor-binding domain (RBD) antibodies induced after severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) vaccination, the assays are not fully comparable in practice. This study evaluated the immunogenicity of the BNT162b2 mRNA vaccine in healthy adults using two immunoassays. METHODS: This prospective cohort study included SARS-CoV-2-naïve adults, predominantly healthcare workers, aged 20-64 years, who received two BNT162b2 vaccine doses between March and May 2021. Blood samples were collected before the first vaccination (S0), before the second vaccination (S1), 4 weeks after the second vaccination (S2), and 6 months after the second vaccination (S3). anti-RBD antibodies were measured using the Architect SARS-CoV-2 IgG II Quant (Abbott Laboratory) and Elecsys anti-SARS-CoV-2 S (Roche Diagnostics) assays. RESULTS: Among the 385 participants, the geometric mean antibody titers (GMTs) on the Architect assay (AU/mL) were 7.5, 693, 7007, and 1030 for S0, S1, S2, and S3, respectively. The corresponding GMTs on the Elecsys assay (U/mL) were 0.40, 24, 928, and 659, respectively. The GMT ratio (S3/S2) was 0.15 on the Architect and 0.71 on the Elecsys assay. The correlation between antibody titers measured with the two assays were strong at all time points after vaccination (Spearman's correlation coefficient: 0.74 to 0.86, P < 0.01 for all). GMT was significantly lower in the older age group after vaccination (P < 0.01), with no significant differences according to sex. Seroprotection (≥5458 AU/mL on the Architect assay and ≥ 753 U/mL on the Elecsys) at each time point was 0 %, 1 %, 67 %, and 1 % on the Architect assay and 0 %, 1 %, 62 %, and 43 % on the Elecsys, respectively. CONCLUSIONS: Two BNT162b2 vaccine doses resulted in adequate anti-RBD antibody response, which varied by age. As the two assays showed different kinetics, the results of single immunoassays should be interpreted with caution.
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COVID-19 , Vacinas Virais , Adulto , Idoso , Anticorpos Antivirais , Vacina BNT162 , COVID-19/prevenção & controle , Humanos , Imunoensaio , Japão , Estudos Prospectivos , SARS-CoV-2 , Vacinação , Vacinas Sintéticas , Vacinas de mRNARESUMO
BACKGROUND/PURPOSE: Klebsiella pneumoniae bacteremia-induced sepsis is a clinically important condition with a high mortality rate and various known virulence factors. However, studies on the association of these virulence factors with the occurrence of K. pneumoniae bacteremia-induced sepsis are scarce. We aimed to investigate clinical variables and virulence factors in patients with K. pneumoniae bacteremia-induced sepsis. METHODS: We retrospectively reviewed the medical records of 76 patients with K. pneumoniae bacteremia between January 2012 and July 2017. Patients were divided into sepsis (n = 25) and non-sepsis (n = 51) groups. Patient background characteristics, antimicrobial regimens, and prognosis were evaluated. We assessed the distribution of virulence factors related to K. pneumoniae, such as mucoviscosity, capsular polysaccharide, and siderophores. Siderophore production levels were determined by measuring the orange halo zone on chrome azurol S agar plate assay. RESULTS: There were no intergroup differences in male-to-female ratio and age. Multivariable analysis revealed that siderophore production level (p < 0.01) was an independent predictor of K. pneumoniae bacteremia-induced sepsis. Furthermore, the optimal cut-off point of siderophore production to predict sepsis was 9.6 mm (sensitivity, 86%; specificity, 76%; AUC, 0.81). CONCLUSION: Siderophore production was an independent predictor of sepsis caused by K. pneumoniae bacteremia. The optimal cut-off point for siderophore production for sepsis occurrence prediction was 9.6 mm. To improve outcomes, patients with K. pneumoniae bacteremia-induced sepsis with high siderophore production levels should be managed prudently.
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Bacteriemia , Infecções por Klebsiella , Sepse , Biomarcadores , Feminino , Humanos , Klebsiella pneumoniae , Masculino , Projetos Piloto , Estudos Retrospectivos , SideróforosRESUMO
OBJECTIVES: To characterize Acinetobacter baumannii OCU_Ac16a, a clinical isolate co-harbouring three acquired carbapenemase genes, bla NDM-1, bla TMB-1, and bla OXA-58, and assess the clinical significance of so-called multiple-carbapenemase producers. METHODS: OCU_Ac16a and its close relative, OCU_Ac16b, which lacks the bla NDM-1, were isolated from sputum cultures of a patient at Osaka City University Hospital. We subjected these strains to whole-genome analysis, particularly focusing on the genetic context of each carbapenemase gene. The transmissibility and functionality of each carbapenemase gene were analysed by conjugation and transformation experiments and antimicrobial susceptibility tests. RESULTS: bla TMB-1 was located in a class 1 integron on the chromosome, whereas bla NDM-1 and bla OXA-58 were found on plasmids named pOCU_Ac16a_2 and pOCU_Ac16a_3, respectively. pOCU_Ac16a_2 (which exhibited highly efficient self-transmissibility) and pOCU_Ac16a_3 (which did not show transmissibility but could be introduced into another A. baumannii strain via electroporation) could both confer carbapenem resistance (MICs ≥512 and ≥32 mg/L, respectively) on the recipient strain. The functionality of bla TMB-1 was evident from the high resistance of OCU_Ac16b to ceftazidime and cefepime (MICs ≥256 and 48 mg/L, respectively), and the high resistance of OCU_Ac16a to cefiderocol (MIC 32 mg/L) could be explained by the additive effect of bla NDM-1 and bla TMB-1. CONCLUSIONS: Our data revealed the genomic organization of OCU_Ac16a and demonstrated that all the carbapenemase genes are functional, each contributing to the extremely high broad-spectrum resistance of OCU_Ac16a to ß-lactams. As multiple-carbapenemase producers can be serious health threats as drug-resistant pathogens and disseminators of carbapenemase genes, close attention should be paid to their emergence.
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Febrile neutropenia, a serious complication that can occur during the treatment of hematological malignancies, can sometimes be fatal owing to fungal infection. Prospective randomized trials indicated the utility of liposomal amphotericin B or caspofungin as an empirical antifungal therapy. Itraconazole, a broad-spectrum tri azole antifungal agent, is poorly absorbed in the intestines after oral absorption and makes it difficult to achieve a stable serum drug concentration. Therefore, an intravenous formulation might offer a potentially safer and more effective alternative. To compare the efficacy and safety of empirical antifungal therapy, patients will be randomly assigned to either the liposomal amphotericin B 3.0 mg/kg once daily group or the intravenous itraconazole 200 mg dose group with five stratification factors (disease risk, previous antifungal prophylaxis, age, sex, and institute). The primary endpoint will be overall favorable response, comprising five secondary endpoints: successful treatment of baseline infection by the end of the treatment; absence of breakthrough infection; no discontinuation of the antifungal treatment due to drug-related toxicity; fever resolution during neutropenia; and 7-day survival after termination of the antifungal treatment. The target sample size of 850 subjects is sufficient to prove the non inferiority of itraconazole compared with liposomal amphotericin B, with a non-inferiority margin of 10%, one sided significance level of 5%, and power of 90%.
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Anfotericina B/efeitos adversos , Antifúngicos/efeitos adversos , Neoplasias Hematológicas/tratamento farmacológico , Itraconazol/efeitos adversos , Neutropenia/tratamento farmacológico , Anfotericina B/administração & dosagem , Antifúngicos/administração & dosagem , Estudos de Equivalência como Asunto , Febre de Causa Desconhecida/tratamento farmacológico , Neoplasias Hematológicas/complicações , Humanos , Itraconazol/administração & dosagem , Estudos Multicêntricos como Assunto , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Acinetobacter pittii isolate OCU_Ac17 was obtained from the venous blood of a patient at a hospital in Japan. We present its complete 4.108-Mbp genome sequence (1 chromosome plus 3 plasmids), analyzed by combining long-read (Flongle) and short-read (MiniSeq) sequencing.
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Here, we report the complete genome sequence of an Acinetobacter baumannii isolate harboring 11 plasmids, obtained at a hospital in Japan in 2016. The complete 4.07-Mbp genome sequence (1 chromosome and 11 plasmids) was analyzed by a combination of long-read (Flongle) and short-read (NovaSeq 6000) sequencing.
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[This corrects the article DOI: 10.1371/journal.pone.0204160.].