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Coronavirus disease 2019 (COVID-19) is associated with coagulopathy. However, the underlying mechanisms are not completely understood. We evaluated the association between COVID-19 coagulopathy and extracellular vesicle (EV) levels. We hypothesized that several EV levels would be higher in COVID-19 coagulopathy patients than in non-coagulopathy patients. This prospective observational study was conducted in four tertiary care faculties in Japan. We enrolled 99 COVID-19 patients (48 with coagulopathy and 51 without coagulopathy) aged ≥20 years who required hospitalization, and 10 healthy volunteers; we divided the patients into coagulopathy and non-coagulopathy groups according to the D-dimer levels (≥1 μg/mL and

We report a severe case of Chromobacterium haemolyticum pneumonia associated with near-drowning and detail the investigation of the pathogen and river water. Our genomic and environmental investigation demonstrated that river water in a temperate region can be a source of C. haemolyticum causing human infections.

Introduction. Bacillus cereus harbouring Ba813, a specific chromosomal marker of Bacillus anthtacis, is found in patients with severe manifestations and causes nosocomial outbreaks. Aim. We assessed the genetic characteristics and virulence of Ba813(+) B. cereus in a hospital setting. Methodology. Three neutropenic patients with haematological malignancy developed B. cereus bacteraemia within a short period. Fifteen B. cereus were isolated from different sites in a haematology ward. A total of 18 isolates were evaluated for Ba813- and B. anthracis -related virulence, food poisoning-related virulence, genetic diversity, bacteria motility and biofilm formation. Results. Ba813(+) B. cereus was detected in 33 % (1/3) of patients and 66 % (9/15) of the hospital environment. The 18 strains were divided into 2 major clusters (clade 1 and clade 2), and 14 strains were classified into clade 1. All Ba813(+) strains, including four sequence types, were classified into clade 1/the cereus III lineage, which is most closely related to the anthracis lineage. Two strains belonging to clade 1/non-cereus III carried the B. anthracis -associated cap gene, but not Ba813. B. cereus, including Ba813(+) strains, had significantly lower prevalence of enterotoxin genes than clade 2 strains. In clade 1, B. cereus , Ba813(+) strains showed significantly higher swimming motility and biofilm formation ability than Ba813(−) strains. Conclusion. Ba813(+) B. cereus , which are genetically closely related to B. anthracis , were abundant in a haematological ward. Ba813(+) B. cereus with high motility and biofilm formation abilities may spread easily in hospital environments, and could become a hospital-acquired infection.

Tuberculosis remains a major public health concern. Millions of tuberculosis cases and associated deaths have been reported worldwide. The Indo-Oceanic lineage Mycobacterium tuberculosis is common in Southeast Asia and causes extrapulmonary lesions. Only a few case studies on this lineage with genetic analysis using whole-genome sequencing have been reported in the literature. We present a case of disseminated tuberculosis, characterized by a variety of extrapulmonary lesions and paradoxical reactions, caused by the Indo-Oceanic lineage M. tuberculosis in a woman in Myanmar. A 22-year-old Burmese woman had arthritis in the right knee, with unknown aetiology, and was referred to our hospital. Computed tomography of the trunk revealed multiple nodular shadows in both lungs; swollen mediastinal lymph nodes; and small, low-density areas in the spleen. M. tuberculosis was detected in the sputum sample, joint aspirate, subcutaneous tumor, and exudate. She experienced a variety of paradoxical reactions together with aggressive tuberculosis dissemination in all areas of the body. Whole-genome sequencing of the DNA of MTB obtained from sputum and the right cervical subcutaneous abscess confirmed the Indo-Oceanic lineage of M. tuberculosis, the predominant strain in Myanmar. The Indo-Oceanic lineage M. tuberculosis causes disseminated tuberculosis all over the body including the periungual region. When patients show unusual symptoms, physicians should consider the introduction of new strains from foreign countries. Genetic analyses of the strains are recommended to define and confirm the lineages.

Highlights • Macrolides are invaluable for the treatment of MPD. • Clarithromycin therapy for MPD can cause severe side effects. • Azithromycin could be a good alternative to clarithromycin for the treatment of MPD., Macrolide-based combination chemotherapy is recommended for the treatment of Mycobacterium avium complex (MAC) pulmonary disease (MPD). The susceptibility of the MAC to macrolide antibiotics (MAs) determines the efficacy of treatment and clinical course of MPD. However, MAs cause several adverse effects, resulting in the discontinuation of macrolide-based combination chemotherapy. We encountered two women aged 65 years and 66 years diagnosed with MPD based on bronchoscopic examinations. They were initially treated with clarithromycin-based combination chemotherapy. However, neither patient could continue with chemotherapy owing to adverse events such as rash and edema. We switched clarithromycin with azithromycin, and the patients were able to continue chemotherapy without adverse events. Both patients completed their treatment successfully. Azithromycin, which also belongs to the class of MAs, can be a promising therapeutic option for MPD in case of clarithromycin intolerance.

The global incidence of nontuberculous mycobacterial pulmonary disease (NTM-PD) has been increasing [1]. Recently popularised microbiology tests, including 16S rRNA sequencing and matrix-assisted laser desorption ionisation–time-of-flight mass spectrometry, have made it possible to identify rare nonmycobacterial species previously unidentifiable using conventional methods [2, 3]. Transmission of Mycobacterium marinum to humans is mainly through direct contact with domesticated fish or through pre-existing wounds or abrasions on limbs exposed to contaminated water [4]. M. marinum causes swimming pool or fish tank granuloma [4]. The organism grows well at 30–32°C, but poorly or not at all at 37°C [4]. Most M. marinum infections do not invade deeper than the superficial cooler regions of the skin, and pulmonary infections are rarely reported [4]., Mycobacterium marinum can cause pulmonary infection and can grow at ≤32°C. Physicians should consider M. marinum when examining patients with pulmonary infection and low body temperature or anorexia nervosa, and grow the specimen at ≤32°C. https://bit.ly/3jkzBeq

We report a coronavirus disease 2019 (COVID-19) case with rheumatoid arthritis taking iguratimod. The patient who continued iguratimod therapy without dose reduction was treated with ciclesonide had an uneventful clinical course, but prolonged detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was observed after resolution of symptoms. The effects of disease-modifying antirheumatic drugs (DMARDs) and ciclesonide on clinical course and viral shedding remain unknown and warrant further investigation.

• COVID-19 patients tend to develop thrombosis. • Detect of hypercoagulopathy is sometimes difficult. • Rotational thromboelastometry is useful for screening.

Acute respiratory distress syndrome (ARDS) is a pathological condition that involves diffuse lung injury and severe hypoxemia caused by pulmonary and systemic diseases. We have established a mouse model of severe ARDS, developed by intratracheal injection of α-galactosylceramide (α-GalCer), an activator of natural killer T (NKT) cells, followed by LPS. In the present study, we used this model to investigate the regulatory mechanism in the early inflammatory response during acute lung injury. In α-GalCer/LPS-treated mice, the number of CD4+ CD25+ Foxp3+ regulatory T (Treg) cells and the expression of a Treg cell-tropic chemokine, secondary lymphoid-tissue chemokine (SLC), in the lungs was significantly lower than in mice treated with LPS alone. Giving recombinant (r)SLC increased the number of Treg cells in α-GalCer/LPS-treated mice. Treatment with anti-IFN-γ mAb enhanced the expression of SLC and the accumulation of Treg cells in the lungs of α-GalCer/LPS-treated mice, whereas giving recombinant (r)IFN-γ reduced the number of Treg cells in mice treated with LPS alone. IL-10 production was significantly lower in α-GalCer/LPS-treated mice than in mice treated with LPS alone. Giving rIL-10 prolonged survival and attenuated lung injury as a result of reduced production of inflammatory cytokines (such as IL-1β, IL-6, TNF-α, and IFN-γ) and chemokines (including MCP-1, RANTES, IP-10, Mig, MIP-2, and KC) in α-GalCer/LPS-treated mice. Treatment with anti-IFN-γ mAb enhanced IL-10 production in α-GalCer/LPS-treated mice. These results suggest that the attenuated accumulation of Treg cells may be involved in the development of severe ARDS through a reduction in the synthesis of IL-10.

Legionella pneumophila causes life-threatening pneumonia culminating in acute lung injury. Innate and adaptive cytokines play an important role in host defense against L. pneumophila infection. Interleukin-36 (IL-36) cytokines are recently described members of the larger IL-1 cytokine family known to exert potent inflammatory effects. In this study, we elucidated the role for IL-36 cytokines in experimental pneumonia caused by L. pneumophila Intratracheal (i.t.) administration of L. pneumophila induced the upregulation of both IL-36α and IL-36γ mRNA and protein production in the lung. Compared to the findings for L. pneumophila-infected wild-type (WT) mice, the i.t. administration of L. pneumophila to IL-36 receptor-deficient (IL-36R-/-) mice resulted in increased mortality, a delay in lung bacterial clearance, increased L. pneumophila dissemination to extrapulmonary organs, and impaired glucose homeostasis. Impaired lung bacterial clearance in IL-36R-/- mice was associated with a significantly reduced accumulation of inflammatory cells and the decreased production of proinflammatory cytokines and chemokines. Ex vivo, reduced expression of costimulatory molecules and impaired M1 polarization were observed in alveolar macrophages isolated from infected IL-36R-/- mice compared to macrophages from WT mice. While L. pneumophila-induced mortality in IL-36α- or IL-36γ-deficient mice was not different from that in WT animals, antibody-mediated neutralization of IL-36γ in IL-36α-/- mice resulted in mortality similar to that observed in IL-36R-/- mice, indicating redundant and overlapping roles for these cytokines in experimental murine L. pneumophila pneumonia.

We reviewed 18 listeriosis cases in Japan and performed molecular analysis of causative Listeria monocytogenes (LM) isolates. Strains genetically related to those from other countries caused various types of listeriosis, including vascular listeriosis in immunocompetent elderly people. Our results highlight the importance of integrated clinical and genomic analysis of LM.

Objectives The aim of this study was to determine the mutant selection window (MSW) of various disinfectants against Staphylococcus aureus and Pseudomonas aeruginosa clinical isolates to determine the tendency of these strains to acquire resistance to disinfectants. Methods A total of 60 S. aureus isolates [30 methicillin-resistant S. aureus (MRSA) and 30 methicillin-susceptible S. aureus (MSSA)] and 30 P. aeruginosa, including 2 multidrug-resistant P. aeruginosa (MDRP), were collected in Japan. The minimum inhibitory concentrations (MICs) and mutant prevention concentrations (MPCs) of disinfectants, including sodium hypochlorite (NaOCl), against these strains were established to determine the MSW. Results The MSW50, MSW80 and MSW100 for sodium hypochlorite against S. aureus and P. aeruginosa were 4×, 8× and 16× MIC, respectively. Strains surviving in the sodium hypochlorite MSW remained at a concentration of ≤0.3% (≤3072 μg/mL). Conclusions This is the first evaluation of the bactericidal activity against S. aureus and P. aeruginosa strains surviving in the MSW of disinfectants. Environmental disinfection at low concentrations of sodium hypochlorite does not kill micro-organisms. Proper use of sodium hypochlorite shows a bactericidal effect against various pathogenic micro-organisms and is inexpensive, making it frequently used globally.

Legionella pneumophila causes life-threatening pneumonia culminating in acute lung injury. Innate and adaptive cytokines play an important role in host defense against L. pneumophila infection. Interleukin-36 (IL-36) cytokines are recently described members of the larger IL-1 cytokine family known to exert potent inflammatory effects. In this study, we elucidated the role for IL-36 cytokines in experimental pneumonia caused by L. pneumophila. Intratracheal (i.t.) administration of L. pneumophila induced the upregulation of both IL-36α and IL-36γ mRNA and protein production in the lung. Compared to the findings for L. pneumophila-infected wild-type (WT) mice, the i.t. administration of L. pneumophila to IL-36 receptor-deficient (IL-36R(−/−)) mice resulted in increased mortality, a delay in lung bacterial clearance, increased L. pneumophila dissemination to extrapulmonary organs, and impaired glucose homeostasis. Impaired lung bacterial clearance in IL-36R(−/−) mice was associated with a significantly reduced accumulation of inflammatory cells and the decreased production of proinflammatory cytokines and chemokines. Ex vivo, reduced expression of costimulatory molecules and impaired M1 polarization were observed in alveolar macrophages isolated from infected IL-36R(−/−) mice compared to macrophages from WT mice. While L. pneumophila-induced mortality in IL-36α- or IL-36γ-deficient mice was not different from that in WT animals, antibody-mediated neutralization of IL-36γ in IL-36α(−/−) mice resulted in mortality similar to that observed in IL-36R(−/−) mice, indicating redundant and overlapping roles for these cytokines in experimental murine L. pneumophila pneumonia.

Excessive inflammation reactions with a cytokine storm in the lungs have historically been thought as the primary cause of fatal acute respiratory distress syndrome (ARDS). However, interruption of inflammatory cytokine activation failed to attenuate ARDS, suggesting that other therapies are required to treat this illness and improve survival. Etoposide (ET), a cytotoxic agent, and prednisolone (PSL), a corticosteroid with strong anti-inflammatory activity, have been used to treat other disease involving similar cytokine-activated macrophages and hemophagocytic activity. However, they have not been previously tested as ARDS therapeutics alone or in combination. In the present study, we used a fatal ARDS mouse model induced via administration of α-galactosylceramide and lipopolysaccharide, which resulted in the development of severe lung injury with hypercytokinemia and hemophagocytosis, all of which were observed in ARDS patients infected with highly pathogenic respiratory viruses. The ET and PSL combination therapy, but not ET or PSL alone, reduced the recruitment and activation of inflammatory cells including macrophages, natural killer T cells, and neutrophils, and significantly improved the survival rate in this model. Furthermore, whereas ET alone improved lung edema, it did not increase the survival rate, indicating the necessity of PSL in the treatment of ARDS. Surprisingly, combination therapy did not reduce the production of cytokines and chemokines in the lungs, demonstrating that inflammatory cells, rather than hypercytokinemia, are the direct target of these compounds and primary cause of ARDS-related death. Thus, combination therapy with ET and PSL that targets inflammatory cells has the potential to attenuate fatal ARDS.

Removal of bacteria by handwashing with ozonated water was evaluated using the ASTM E1174 standard test method. Thirty healthy volunteers were assigned randomly to three groups: ozonated water, antimicrobial soap and water, and non-antimicrobial soap and water. A 3 log10 cfu reduction was achieved by washing hands with ozonated water or antimicrobial soap and water. However, ozonated water was not significantly superior to non-antimicrobial soap and water. Ozonated water may remove bacteria from the hands to at least a similar extent as that by non-antimicrobial soap and water in the absence of visible dirt or body fluid contamination.

Introduction. This is the first case report of septic abortion due to β-lactamase-negative ampicillin-resistant (BLNAR) non-typeable Haemophilus influenzae infection. In Japan, BLNAR H. influenzae is widespread and has become a clinical concern, especially in paediatrics and otolaryngology, but H. influenzae has not been previously recognized as a causative agent of obstetric or gynaecological infection. Case presentation. A 31-year-old pregnant woman presented at 17 weeks and 6 days of gestation with a high fever; she was admitted with a diagnosis of threatened premature delivery. Despite tocolytic treatment, she aborted spontaneously 2 h after admission and then entered septic shock. BLNAR H. influenzae was detected in both blood and vaginal cultures. Her condition gradually improved after several days of treatment with cefotaxime, and she was ultimately discharged without sequelae or complaints. Conclusion. Although penicillin with a β-lactamase inhibitor is currently recommended for the treatment of septic abortion, this combination will probably lead to treatment failure in the case of BLNAR H. influenzae infection. As this study reveals, H. influenzae can cause septic abortion; hence, future efforts should be undertaken to detect and therapeutically target this pathogen during pregnancy.

Acute respiratory distress syndrome (ARDS) is a pathological condition that involves diffuse lung injury and severe hypoxemia caused by pulmonary and systemic diseases. We have established a mouse model of severe ARDS, developed by intratracheal injection of α-galactosylceramide (α-GalCer), an activator of natural killer T (NKT) cells, followed by LPS. In the present study, we used this model to investigate the regulatory mechanism in the early inflammatory response during acute lung injury. In α-GalCer/LPS-treated mice, the number of CD4

To the Editor: Infected abdominal aortic aneurysm (IAAA) is uncommon, but life-threatening; the mortality rate ranges from 25% to30% (1,2). Identification of the pathogen is essential for diagnosis and treatment. Previous studies have shown that species of the genera Salmonella, Staphylococcus, and Streptococcus are the most common pathogens associated with IAAA, but a causative organism is not identified in 14%–40% of patients (1,2). Helicobacter cinaedi has mainly been isolated from immunocompromised patients with bacteremia, cellulitis, and septic arthritis (3,4). Here, we report 3 cases of IAAA caused by H. cinaedi detected by 16S ribosomal RNA (16S rRNA) gene analysis. The 3 patients (case-patients 1–3) were referred to Tohoku University Hospital, Sendai, Japan, for surgical treatment of IAAA in 2013. None had a history of disease known to cause immunodeficiency. Because their abdominal aneurysms enlarged rapidly, all 3 patients underwent resection of the aneurysm and extensive local debridement and irrigation. Histopathologic examination of the surgical specimens revealed severe atherosclerosis and inflammation, consistent with a diagnosis of IAAA. For each case-patient, blood culture (BacT/ALERT; bioMerieux Industry, Tokyo, Japan) was negative, as was culture of surgically removed tissue on HK semisolid agar (Kyokuto Pharmaceutical Industrial Co., Ltd., Tokyo, Japan) at 35°C under aerobic conditions for 7 days for enrichment of microorganisms, and on chocolate agar at 35°C under 5% CO2 for 48 h. We then used 16S rRNA gene analysis to identify a pathogen. We extracted DNA from resected tissues using a QIAamp DNA Mini kit (QIAGEN K.K., Tokyo, Japan), amplified it using PCR, and sequenced it using universal primers for 16S rRNA (5). We used the EzTaxon-e Database for sequence analysis (http://eztaxon-e.ezbiocloud.net/), which revealed that the 16S rRNA gene sequence of bacteria in the aneurysmal tissues was identical to that of H. cinaedi. For case-patient 3, we cultured microaerophilic tissue at 35°C using Trypticase Soy Agar II with 5% sheep blood (Kyokuto Pharmaceutical Industrial Co.) and an Anaero Pouch-MicroAero (Mitsubishi Gas Chemical Co., Inc., Tokyo, Japan) to detect H. cinaedi. We observed bacterial colonies, after Gram staining, which showed gram-negative spiral rods. By 16S rRNA gene analysis, we confirmed that the isolate was H. cinaedi. For each of the 3 case-patients, species identification was further confirmed by sequence analysis of 23S ribosomal RNA (23S rRNA) (DNA Data Bank of Japan: http://blast.ddbj.nig.ac.jp/blastn?lang = ja) and amplification of the gyrB gene region that is specific to H. cinaedi (6,7). In samples from the 3 patients, there were mutations of the 23S rRNA gene and amino acid substitutions in GyrA related to macrolide and fluoroquinolone resistance, respectively (6,8). After identifying the pathogen, we selected antimicrobial agents based on the reported drug susceptibility profile of H. cinaedi (6,8). The patients survived and are being followed up as outpatients. Clinical and molecular characteristics of the 3 cases of IAAA with H. cinaedi infection are shown in the Table. Table Clinical characteristics of 3 patients with Helicobacter cinaedi–infected abdominal aortic aneurysms and molecular characteristics of isolates, Japan * Although the high negative culture rate for pathogens causing IAAA had been explained by prolonged preoperative antimicrobial drug therapy (2), another possibility is that H. cinaedi may be a causative organism. Earlier research has suggested that H. cinaedi infections can remain undiagnosed or be incorrectly diagnosed because of difficulty in isolating this microorganism (9). H. cinaedi grows slowly under microaerophilic conditions, but no current standard laboratory methods result in a diagnosis of this pathogen (6,7,9). We isolated H. cinaedi from surgically removed tissue from case-patient 3 by microaerophilic culture after taking this pathogen into consideration. For diagnosis of H. cinaedi infections, methods leading to accurate identification by clinical microbiological laboratories are needed. Currently, H. cinaedi is identified by molecular analysis of the 16S rRNA gene (6,7,10). In addition, matrix-assisted laser desorption/ionization–time-of-flight mass spectrometry (MALDI-TOF MS) (10), may become a useful tool for this purpose. Standard breakpoints of antimicrobial drugs for H. cinaedi have not been defined, but all isolates in this study had mutations that indicated resistance to macrolides and fluoroquinolones. For adequate treatment for H. cinaedi infections, guidelines for selection of antimicrobial drugs and surveillance of its antimicrobial susceptibility profile are required. During November 2012–November 2013, 8 patients underwent their first operation for IAAA at the university hospital. We used 16S rRNA gene analysis of surgical tissues and culture of blood and tissue specimens to detect pathogens (data not shown). Identification of H. cinaedi in 3 of 8 patients suggests that it could be a prevalent pathogen related to IAAA. Taking such information into consideration could affect the prognosis of many patients. Accordingly, tissue should be cultured while considering H. cinaedi infection in patients with IAAA. H. cinaedi colonizes the gastrointestinal tract, and bacterial translocation may lead to bacteremia associated with mucosal damage (4). However, the route of transmission and reason most H. cinaedi infections have been reported in Japan are unclear. To clarify the relationship between H. cinaedi and IAAA, further clinical and epidemiologic studies are needed. Meanwhile, we recommend clinical consideration of H. cinaedi infection, use of appropriate laboratory procedures to identify cases, and development of treatment guidelines.

Acinetobacter baumannii is generally the most frequently isolated Acinetobacter species. Sequence analysis techniques allow reliable identification of Acinetobacter isolates at the species level. Forty-eight clinical isolates of Acinetobacter spp. were obtained from blood cultures at Tohoku University Hospital. These isolates were identified at the species level by partial sequencing of the RNA polymerase β-subunit ( rpoB ), 16S rRNA, and gyrB genes. Then further characterization was done by using the PCR for detection of OXA-type β-lactamase gene clusters, metallo-β-lactamases, and carO genes. Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing were also performed. The most frequent isolate was Acinetobacter soli (27.1%). Six of the 13 A. soli isolates were carbapenem nonsusceptible, and all of these isolates produced IMP-1. PFGE revealed that the 13 A. soli isolates were divided into 8 clusters. This study demonstrated that A. soli accounted for a high proportion of Acinetobacter isolates causing bacteremia at a Japanese tertiary hospital. Non- A. baumannii species were identified more frequently than A. baumannii and carbapenem-nonsusceptible isolates were found among the non- A. baumannii strains. These results emphasize the importance of performing epidemiological investigations of Acinetobacter species.

Background Shiga toxin-producing Escherichia coli (STEC) causes serious gastrointestinal illness. Although O157 is predominant, non-O157 infections have been increasingly reported worldwide. We used whole-genome sequencing (WGS) to investigate molecular characteristics and phylogeny of STEC isolates. Methods A total of 22 STEC isolates from symptomatic patients (n = 13) and asymptomatic carriers (n = 9) in a Japanese region during 2016–2017 were used. Serogroups were O157, O26 and O103 (n = 5, 12, and 5, respectively). WGS was performed using an Illumina Miseq. Genomic analysis was performed using web-based tools by the Center for Genomic Epidemiology. Single nucleotide polymorphism detection and construction of phylogenetic tree were performed using Mauve software. Results Of 76 virulence genes, 32 (42%) were detected (Figure 1). Eighteen (82%) and 7 (32%) isolates contained stx1 and stx2, respectively. Twelve (91%) contained eae. stx2 was more frequent in isolates from patients (P < 0.05), whereas cba was more frequent in isolates from carriers (P < 0.05). stx2, etpD were more frequent in O157 isolates (P < 0.05, respectively), whereas stx1, efa1, cif, tccP, cba, lpfA were more frequent in non-O157 isolates (P < 0.05, respectively). Nine acquired resistance gene (aph(3′)-Ia, blaTEM-1b, dfrA5, dfrA8, strA, strB, sul2, tetA, tetB) were detected, while at least one was found in 6 (27%) isolates. Isolates from patients (5/13, 38%) were likely to have more resistance genes than isolates from carriers (1/9, 11%) (P = 0.33). Genotyping and multilocus sequence typing revealed all O26 isolates belonged to O26:H11 ST21, O103 belonged to O103:H2 ST17 and novel O103:H8 ST2836, while O157 belonged to O157:H7 ST11 and ST2966 (Figure 2). Phylogenetic tree showed O103:H8 ST2836 isolates clustered with O26, separated from O103:H2 ST17 (Figure 3). In a cluster of O26:H11 ST21 isolates, isolates from carriers formed a subcluster. O157 isolates clustered in a separate lineage. O157:H7 ST2966 isolates evolved from ST11. Conclusion Of the non-O157 isolates, O26:H11 ST21, which contained as many virulence genes as O157, was prevalent among both patients and carriers in our region, highlighting the importance of monitoring genomic characteristics of non-O157 STEC. Disclosures All authors: No reported disclosures.

Shiga toxin-producing Escherichia coli (STEC) can cause severe gastrointestinal disease and colonization among food handlers. In Japan, STEC infection is a notifiable disease, and food handlers are required to undergo routine stool examination for STEC. However, the molecular epidemiology of STEC is not entirely known. We investigated the genomic characteristics of STEC from patients and asymptomatic food handlers in Miyagi Prefecture, Japan. Whole-genome sequencing (WGS) was performed on 65 STEC isolates obtained from 38 patients and 27 food handlers by public health surveillance in Miyagi Prefecture between April 2016 and March 2017. Isolates of O157:H7 ST11 and O26:H11 ST21 were predominant (n = 19, 29%, respectively). Non-O157 isolates accounted for 69% (n = 45) of all isolates. Among 48 isolates with serotypes found in the patients (serotype O157:H7 and 5 non-O157 serotypes, O26:H11, O103:H2, O103:H8, O121:H19 and O145:H28), adhesion genes eae, tir, and espB, and type III secretion system genes espA, espJ, nleA, nleB, and nleC were detected in 41 to 47 isolates (85–98%), whereas isolates with other serotypes found only in food handlers were negative for all of these genes. Non-O157 isolates were especially prevalent among patients younger than 5 years old. Shiga-toxin gene stx1a, adhesion gene efa1, secretion system genes espF and cif, and fimbrial gene lpfA were significantly more frequent among non-O157 isolates from patients than among O157 isolates from patients. The most prevalent resistance genes among our STEC isolates were aminoglycoside resistance genes, followed by sulfamethoxazole/trimethoprim resistance genes. WGS revealed that 20 isolates were divided into 9 indistinguishable core genomes (

Culture-negative endocarditis remains a diagnostic and therapeutic challenge despite recent medical advances. Streptococcus tigurinus, a novel member of the Streptococcus mitis group, was first identified in Zurich. S. tigurinus possesses virulence determinants and causes invasive infections. We report a case of culture-negative endocarditis with serious complications due to S. tigurinus, which was identified by 16S ribosomal RNA gene sequence analysis of excised valve tissue specimens. This technique is useful for identification of the causative microorganism in patients with culture-negative endocarditis and may facilitate early diagnosis and appropriate antimicrobial treatment.

Summary Acute respiratory distress syndrome (ARDS) is accompanied by severe lung inflammation induced by various diseases. Despite the severity of the symptoms, therapeutic strategies have been ineffective. High mobility group box 1 (HMGB1), which was identified originally as a DNA binding protein, has been proposed as a mediator of acute lung injury. In addition to its anti-coagulant activity, recombinant thrombomodulin (rTM) possesses an ability to suppress the inflammatory response through neutralizing HMGB1. T regulatory (Treg) cells in the lungs are reported to modify innate immune responses during resolution of acute lung injury. In the present study, we investigated the therapeutic effect of rTM, and the contribution of Treg cells to this effect, in a mouse model of severe ARDS. C57BL/6 mice received sequential intratracheal administration of α-galactosylceramide (α-GalCer) and lipopolysaccharide (LPS), which resulted in the development of severe ARDS. HMGB1 levels in the lungs increased to a higher level in ARDS mice compared to those in mice treated with LPS alone. HMGB1 was expressed in the infiltrating neutrophils and macrophages in lungs. Treg cells were reduced significantly in the lungs of ARDS mice compared to those in mice treated with LPS alone. rTM administration prolonged the survival time and ameliorated the development of ARDS, which was associated with increased Treg cells and synthesis of interleukin (IL)-10 and transforming growth factor (TGF)-β in the lungs. These results suggest that HMGB1 is involved in the development of severe ARDS and rTM shows therapeutic effects through promoting the accumulation of Treg cells at the inflammatory sites.

Acute respiratory distress syndrome (ARDS) is accompanied by severe lung inflammation induced by various diseases. Despite the severity of symptoms, therapeutic strategies for this pathologic condition are still poorly developed. Interferon (IFN)-α is well known as an antiviral cytokine and low-dose IFN-α has been reported to show antiinflammatory effects. Therefore, we investigated how this cytokine affected ARDS in a mouse model. C57BL/6 mice received sequential intratracheal administration of α-galactosylceramide (α-GalCer) and lipopolysaccharide (LPS), which resulted in the development of fulminant ARDS. These mice were then treated intranasally with IFN-α and their survival, lung weight, pathological findings, and cytokine production were evaluated. Administration of low-dose IFN-α prolonged survival of fulminant ARDS mice, but higher doses of IFN-α did not. Histological analysis showed that low-dose IFN-α treatment improved findings of diffuse alveolar damage in fulminant ARDS mice, which was associated with reduction in the wet/dry (W/D) lung weight ratio. Furthermore, IFN-γ production in the lungs was significantly reduced in IFN-α-treated mice, compared with control mice, but tumor necrosis factor (TNF)-α production was almost equivalent for both groups. Low-dose IFN-α shows antiinflammatory and therapeutic effects in a mouse model of fulminant ARDS, and reduced production of IFN-γ in the lung may be involved in the beneficial effect of this treatment.