A case of Bordetella trematum and Kerstersia gyiorum infections in a patient with congestive dermatitis.

Bordetella trematum and Kerstersia gyiorum are rare gram-negative bacilli that are not frequently detected in human infections. In this report, we describe a case of a 48-year-old man who presented to our hospital with an infected wound on his leg. Discharges from the cracks of the granulation were collected and evaluated in our microbiology laboratory. Gram staining of the specimen showed polymorphonuclear leukocytes and abundant gram-negative bacilli. Three types of colonies were isolated on blood agar and were identified as B. trematum and Alcaligenes faecalis using VITEK MS. Moreover, K. gyiorum and B. trematum were identified and confirmed via 16S ribosomal RNA (rRNA) gene sequencing. The patient successfully recovered following application of meropenem antibacterial therapy and surgical debridement. This is the first reported case of complex wound infection caused by both B. trematum and K. gyiorum. Identification of B. trematum has recently been made possible by routine bacterial identification using matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS). However, K. gyiorum isolation is still rare, and species identification requires 16S rRNA sequencing. Thus, this case highlighted the importance of using multiple methods, such as MALDI-TOF MS and 16S rRNA gene sequencing, for identification of rarely isolated species from clinical specimens.

Factors associated with viral clearance periods from patients with COVID-19: A retrospective observational cohort study.

INTRODUCTION: Knowledge is limited on the virologic course of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection, particularly the time taken for viral clearance and the optimal time to discontinue isolation. This study aims to identify the clinical and demographic factors influencing the time taken for viral clearance in patients with COVID-19 to determine the optimal isolation period. METHODS: This two-center retrospective observational cohort study was conducted between March 1 and June 31, 2020. Patients with COVID-19, which was confirmed by real-time reverse transcription polymerase chain reaction, were included. Data were extracted from medical records. The positive duration, which was defined as the period from the day of symptom onset to the negative conversion day, was assessed using a generalized linear model. RESULTS: We included 63 patients. The mean positive duration was 20 days. The positive duration was significantly shorter for patients younger than 30 years of age and those between 30 and 60 years of age than for patients older than 60 years of age. We observed a more scattered distribution of the positive duration in older patients than in younger patients. CONCLUSIONS: Younger patients who recovered from COVID-19 took less time to clear SARS-CoV-2 than older patients; thus, a classification of the isolation periods based on age could be considered. A uniform viral clearance period for older patients may be difficult to determine because of biases such as underlying medical conditions. Further surveillance measures are recommended to determine the viral clearance time and the optimal isolation period.

Preparation of cerium molybdates and their antiviral activity against bacteriophage Φ6 and SARS-CoV-2.

Two cerium molybdates (Ce2Mo3O12 and γ-Ce2Mo3O13) were prepared using either polymerizable complex method or hydrothermal process. The obtained powders were almost single-phase with different cerium valence. Both samples were found to have antiviral activity against bacteriophage Φ6. Especially, γ-Ce2Mo3O13 exhibited high antiviral activity against both bacteriophage Φ6 and SARS-CoV-2 coronavirus, which causes COVID-19. A synergetic effect of Ce and molybdate ion was inferred along with the specific surface area as key factors for antiviral activity.

Comparison between IMP carbapenemase-producing Enterobacteriaceae and non-carbapenemase-producing Enterobacteriaceae: a multicentre prospective study of the clinical and molecular epidemiology of carbapenem-resistant Enterobacteriaceae.

BACKGROUND: Carbapenem-resistant Enterobacteriaceae (CRE) are classified as carbapenemase-producing Enterobacteriaceae (CPE) and non-CPE; the majority of CPE in Japan produce IMP carbapenemase. OBJECTIVES: We evaluated the clinico-epidemiological and microbiological information and effects of IMP-type carbapenemase production in CRE. METHODS: Patients with isolations of CRE (MICs of meropenem ≥2 mg/L, imipenem ≥2 mg/L or cefmetazole ≥64 mg/L) from August 2016 to March 2018 were included. Microbiological analyses and WGS were conducted and clinical parameters were compared between groups. Independent predictors for the isolation of CPE from patients were identified by logistic regression. For comparing clinical outcomes, a stabilized inverse probability weighting method was used to conduct propensity score-adjusted analysis. RESULTS: Ninety isolates (27 CPE and 63 non-CPE) were collected from 88 patients (25 CPE and 63 non-CPE). All CPE tested positive for IMP carbapenemase. Antibiotic resistance (and the presence of resistance genes) was more frequent in the CPE group than in the non-CPE group. Independent predictors for CPE isolation were residence in a nursing home or long-term care facility, longer prior length of hospital stay (LOS), use of a urinary catheter and/or nasogastric tube, dependent functional status and exposure to carbapenem. Although in-hospital and 30 day mortality rates were similar between the two groups, LOS after CRE isolation was longer in the CPE group. CONCLUSIONS: IMP-CPE were associated with prolonged hospital stays and had different clinical and microbiological characteristics compared with non-CPE. Tailored approaches are necessary for the investigational and public health reporting, and clinical and infection prevention perspectives for IMP-CPE and non-CPE.

Environmental Presence and Genetic Characteristics of Carbapenemase-Producing Enterobacteriaceae from Hospital Sewage and River Water in the Philippines.

This study aimed to evaluate the prevalence and genetic characteristics of carbapenemase-producing Enterobacteriaceae (CPE) in hospital sewage and river water in the Philippines, which has a typical tropical maritime climate. We collected 83 water samples from 7 hospital sewage and 10 river water sites. CPE were identified using CHROMagar mSuperCARBA, and Gram-negative strains were identified using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) or 16S rRNA gene sequencing. Resistance genes in Enterobacteriaceae strains were identified using PCR and DNA sequencing, and transferability of carbapenemase genes from the CPE was investigated with conjugation experiments. Genotyping was performed using multilocus sequence typing (MLST) for Escherichia coli and Klebsiella pneumoniae Out of 124 Enterobacteriaceae isolates, we identified 51 strains as CPE and divided these into 7 species, 11 E. coli, 14 Klebsiella spp., 15 Enterobacter spp., and 11 others, including 4 additional species. Conjugation experiments via broth mating and using E. coli J53 revealed that 24 isolates can transfer carbapenemase-encoding plasmids. MLST analysis showed that 6 of 11 E. coli isolates belonged to clonal complex 10 (CC10). Of 11 K. pneumoniae strains, 9 unique sequence types (STs) were identified, including ST147. Five types of carbapenemase genes were identified, with the most prevalent being NDM (n = 39), which is epidemic in clinical settings in the Philippines. E. coli CC10 and K. pneumoniae ST147, which are often detected in clinical settings, were the dominant strains. In summary, our results indicate that hospital sewage and river water are contaminated by CPE strains belonging to clinically important clonal groups.IMPORTANCE Carbapenemase-producing Enterobacteriaceae (CPE) cause severe health care-associated infections, and their increasing prevalence is a serious concern. Recently, natural ecosystems have been recognized as important reservoirs of antibiotic resistance genes. We investigated the prevalence and genetic characteristics of CPE isolated from the environment (hospital sewage and river water) in the Philippines and found several CPE, including Escherichia coli and other species, with different carbapenemases. The most prevalent carbapenemase gene type was NDM, which is endemic in clinical settings. This study revealed that isolates belonging to carbapenemase-producing E. coli CC10 and K. pneumoniae sequence type 147 (ST147), which are often detected in clinical settings, were dominant in the natural environment. Our work here provides a report on the presence and characteristics of CPE in the environment in the Philippines and demonstrates that both hospital sewage and river water are contaminated by CPE strains belonging to clinically important clonal groups.

Trends and molecular characteristics of carbapenemase-producing Enterobacteriaceae in Japanese hospital from 2006 to 2015.

BACKGROUND: The increasing number of carbapenemase-producing Enterobacteriaceae (CPE) has become a global problem. Most carbapenemases detected in Japan are imipenemase, which is an imipenem-degrading enzyme with low ability; thus, CPE could have been overlooked. Therefore, this study aimed to detect and analyze CPE, without overlooking CPE showing the low minimum inhibitory concentration phenotype. METHODS: CPE screening was conducted on 531 ceftazidime-resistant Enterobacteriaceae isolated from Kitasato University Hospital during 2006-2015. We confirmed the presence of the carbapenemase genes (blaIMP, blaVIM, blaKPC, blaNDM, and blaOXA-48) by multiplex polymerase chain reaction. The detected CPE strains were analyzed by antimicrobial susceptibility testing, multilocus sequence typing, conjugal experiments, replicon typing, and plasmid profiling by restriction enzyme treatment. RESULTS: The CPE detection rate in Kitasato University Hospital within the past 10 years was 0.0003% (nine CPE strains). These nine CPE strains were identified to harbor 8 blaIMP-1 or 1 blaNDM-5. The CPE strains consisted of five species including Klebsiella pneumoniae and Citrobacter freundii. Six of eight blaIMP-1 were coded by IncHI2 plasmid, and the other two were coded by IncA/C plasmid. Plasmid profiling revealed that K. pneumoniae and C. freundii isolated from the same patient harbored the same plasmid. CONCLUSION: The CPE detection rate in this study was significantly lower than those previously reported in Japan. In one case, IncA/C plasmid transmission through different bacterial species within the body was speculated. Although the number of CPE detected was low, these results indicated that the resistance plasmid could spread to other bacterial species.

Spinal epidural abscess caused by non-typhoidal Salmonella: A case report and literature review.

Non-typhoidal Salmonellae are Gram negative bacilli commonly causing self-limiting gastroenteritis, representing a public health issue particularly in tropical countries. Further, the epidemiology of invasive infection by non-typhoidal Salmonella species is poorly understood. Herein, we presented a case of an unusual Salmonella enterica subsp. enterica serovar Altona epidural abscess that cause osteomyelitis and psoas abscess in a 52-year-old Japanese man. To ensure adequate antibiotics penetration into the epidural space, the patient was treated with antibiotics in doses similar to those administered for meningitis. We also reviewed the literature on patients who developed non-typhoidal Salmonella epidural abscesses, and we found 10 other previously reported cases. Salmonella Enteritidis was the pathogen most commonly identified, similar to gastroenteritis. More surveillance of non-typhoidal Salmonella serovars, especially in cases of severe infection, and investigation of antibiotic penetration rate into the epidural space are warranted to decide the best treatment course.

The seventh nationwide surveillance of six otorhinolaryngological infectious diseases and the antimicrobial susceptibility patterns of the isolated pathogens in Japan.

The Japanese Three Academic Societies Joint Antimicrobial Susceptibility Surveillance Committee conducted a nationwide surveillance on six otorhinolaryngological diseases and investigated the antimicrobial susceptibility patterns and isolation rates of the causative pathogens. The surveillance program was conducted in the otorhinolaryngological departments of 12 universities, and 36 affiliated hospitals and clinics. Patients with acute otitis media (children under six years old), chronic otitis media, acute nasal sinusitis, chronic nasal sinusitis, acute tonsillitis, and peritonsillar abscess (over 20 years old) between December 2015 and June 2017 were investigated. The collected swab or incision samples were cultivated for microbial identification, and the antimicrobial susceptibility of the detected bacteria was measured at the Kitasato University Research Center for Infections and Antimicrobials. The surveillance focused on three gram-positive bacteria (Streptococcus pneumoniae, Streptococcus pyogenes, and Staphylococcus aureus), three gram-negative bacteria (Haemophilus influenzae, Moraxella catarrhalis, and Pseudomonas aeruginosa), and three anaerobic bacteria (anaerobic gram-positive cocci, Prevotella spp., Porphyromonas spp., and Fusobacterium spp.). Bacterial susceptibility to 40 antimicrobial agents was investigated. We were unable to completely mitigate the rise in the occurrence of resistant bacteria, such as methicillin-resistant S. aureus, penicillin-resistant S. pneumoniae, penicillin-intermediate resistant S. pneumoniae, beta-lactamase non-producing ampicillin-resistant H. influenzae, and beta-lactamase producing ampicillin-resistant H. influenzae. We suggest promoting the proper usage of antimicrobial agents to prevent the spread of these bacteria. We also suggested that immunization with pneumococcal vaccines is useful for decreasing the occurrence of otorhinolaryngological infectious diseases caused by pneumococci.

Filifactor alocis brain abscess identified by 16S ribosomal RNA gene sequencing: A case report.

We report a clinical case of Filifactor alocis brain abscess in an 85-year-old man who had decayed teeth 1 week prior. In this case, the abscess was surgically drained after empirical antibiotics had been initiated. Although the causative organism could not be identified by culture, F. alocis was detected via 16S ribosomal RNA (16S rRNA) gene sequencing of the pus isolated from the abscess. The patient recovered without serious sequelae after surgical drainage and prolonged antibiotic treatment, including metronidazole, ceftriaxone and meropenem for 8 weeks. The findings in this case emphasize that 16S rRNA gene sequencing allows bacterial diagnosis of brain abscess when phenotypic identification fails, such as in cases where patients are undergoing antimicrobial treatment at the time of sampling or where patients are infected with fastidious organisms.

Peritonitis due to Moraxella osloensis: A case report and literature review.

A-26-year-old man was admitted to our hospital with diffuse abdominal pain, nausea, and vomiting. He had a history of malignant nephrosclerosis, for which he had been receiving peritoneal dialysis (PD) for the past 14 months. His PD effluent was cloudy and turbid (white blood cell count, 10,528/µL; neutrophils 95.2%). A Gram-negative coccobacillus was isolated from peritoneal fluid culture. However, the organism could not be identified by matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) (Vitek MS, bioMérieux), but was identified as Moraxella osloensis by the 16S rRNA gene sequencing. He was successfully treated with intraperitoneal cefazolin therapy for 3 weeks without removing the intra-abdominal catheter. A literature review revealed three previous case reports all of which were diagnosed by MALDI Biotyper (Bruker Daltonics), suggesting that the identification of M. osloensis may vary depending on the type of MALDI-TOF MS system. In conclusion, we experienced a case of M. osloensis infection in a PD patient, which was successfully treated by antibiotic treatment, without removing the PD catheter.

Case of endobronchial metastasis from breast cancer accompanied with Cunninghamella bertholletiae tracheobronchial mycetoma.

Cunninghamella is a member of the class Zygomycetes. Cunninghamella species include ubiquitous filamentous fungi; infections caused by Cunninghamella species are less frequent but have higher mortality rates than infections caused by Mucorales group members such as Rhizopus and Mucor. Herein, we reported a rare fatal case of endobronchial metastasis from breast cancer accompanied with Cunninghamella bertholletiae tracheobronchial mycetoma. A 73-year-old female with a history of right-sided breast cancer who had undergone mastectomy 11 years previously and had no recurrence presented to our emergency department with a 1-week history of left-sided back pain. Chest X-ray revealed left lung atelectasis; bronchoscopy revealed an endobronchial mass lesion in the left main bronchus. Pathological examination revealed fungal mycetoma but malignant lesions were not detected. Endobronchial and lung mycetoma caused by Cunninghamella bertholletiae were initially diagnosed; liposomal amphotericin B was administered, but her condition deteriorated. Rigid endoscopy showed growth of hemorrhagic tissue occupying the left main bronchus just under the carina. Pathological examination of the shaved lesion revealed metastasis from breast cancer covered with abundant necrotic tissue. No mold was observed in the necrotic tissue; this was probably due to liposomal amphotericin B treatment. To our knowledge, this is the first case of endobronchial metastasis from breast cancer accompanied with Cunninghamella bertholletiae mycetoma. Distinguishing endobronchial metastases from breast cancer and atypical presentations of Cunninghamella endobronchial mycetomas can be very difficult. Repeated bronchoscopies maybe helpful in establishing an accurate diagnosis when clinical prognosis does not match the initial diagnosis.

Biofilm-Forming by Carbapenem Resistant Enterobacteriaceae May Contribute to the Blood Stream Infection.

Bloodstream infection (BSI) due to carbapenem-resistant Enterobacteriaceae (CRE) has a high mortality rate and is a serious threat worldwide. Ten CRE strains (eight Enterobacter cloacae, one Klebsiella pneumoniae and one Citrobacter freundii) were isolated from the blood of nine patients, a percentage of whom had been treated with indwelling devices. The steps taken to establish cause included minimum inhibitory concentration (MIC) tests, a pulsed-field gel electrophoresis (PFGE), biofilm study, a multiplex PCR for resistant genes of carbapenemases and extended-spectrum beta-lactamases (ESBLs), and plasmid incompatibility typing. All strains showed a tendency toward resistance to multiple antibiotics, including carbapenems. Frequently isolated genes of ESBLs and carbapenemases include blaTEM-1 (four strains), blaSHV-12 (four strains) and blaIMP-1 (six strains). A molecular analysis by PFGE was used to divide the XbaI-digested genomic DNAs of 10 CRE strains into eight patterns, and the analysis showed that three E. cloacae strains detected from two patients were either identical or closely related. The biofilm production of all CRE strains was examined using a microtiter biofilm assay, and biofilm growth in continuous flow chambers was observed via the use of a confocal laser scanning microscope. Our study indicates that biofilm formation on indwelling devices may pose a risk of BSI due to CRE.

Rat-Bite Fever in Human with Streptobacillus notomytis Infection, Japan.

We report a case of rat-bite fever in a 94-year-old woman with Streptobacillus notomytis infection. We established an epidemiologic link between exposure to rats and human infection by performing nested PCRs that detected S. notomytis in the intraoral swab specimens obtained from rats captured in the patient's house.

Molecular diagnosis and characterization of a culture-negative mycotic aneurysm due to ST54 Haemophilus influenzae type b with PBP 3 alterations.

Mycotic aneurysm is a rare but life-threatening disease that warrants an integrated therapeutic approach involving surgical intervention and prolonged antibiotic use. However, the causative organisms are often unidentified because antibiotics started empirically render blood and tissue cultures negative. Molecular diagnosis has been reported to be useful in such culture-negative cases. We report a case of a culture-negative mycotic aortic aneurysm due to Haemophilus influenzae, diagnosed by direct 16S rRNA polymerase chain reaction (PCR) and sequencing of the resected aneurysm tissue. PCR for serotype revealed type b, and PCR and sequencing of the ftsI gene revealed alterations in penicillin-binding protein 3, suggesting resistance to ampicillin. Multilocus sequence typing demonstrated that the isolate belonged to sequence type 54.

A first case of isolation of Kerstersia gyiorum from urinary tract.

An 82-year-old man with percutaneous nephrostomy presented to our Hospital with dysuria for one day. The patient's percutaneous nephrostomy tube was exchanged, with about 20 mL of creamy purulent urine being collected. Direct smear of the urine specimen showed polymorphonuclear leukocytes and small Gram-negative bacilli, some of which had undergone phagocytosis. This organism was identified as Kerstersia gyiorum using 16S ribosomal RNA gene analysis. He was successfully recovered with exchange of his percutaneous nephrostomy tube and fluoroquinolone internal use treatment. This is the first case report of urinary tract infection due to K. gyiorum.

Bacteremia secondary to Alloscardovia omnicolens urinary tract infection.

A 70-year-old woman was admitted to our hospital with malaise, bilateral leg edema, and oliguria. She had a history of advanced uterine cancer. Bilateral double-J catheters were inserted because growth of intra-abdominal metastases led to bilateral ureteral stricture and hydronephrosis. Two days later, she suddenly developed high fever. Thin gram-positive bacilli of moderate length were detected in the anaerobic blood culture bottles. We performed 16S ribosomal RNA analysis of the isolate and it showed 100% match with Alloscardovia omnicolens DSM 21503(T). She was successfully treated with cefmetazole in addition to percutaneous nephrostomy.

First report of severe acute otitis media caused by Campylobacter rectus and review of the literature.

Campylobacter rectus is a member of the human oral flora and is associated with periodontal disease. We report the first case of severe acute otitis media (AOM) due to C. rectus in a previous healthy 15-year-old boy, which was confirmed by 16S ribosomal RNA gene sequencing. C. rectus is a possible causative pathogen of AOM.

First confirmed case of spondylodiscitis with epidural abscess caused by Parvimonas micra.

Parvimonas micra was renamed species as within Gram-positive anaerobic cocci and rarely causes severe infections in healthy people. We report the first confirmed case of spondylodiscitis with epidural abscess caused by P. micra in a healthy women. The patient has a pain in low back and anterior left thigh. Magnetic resonance imaging and computed tomography detected the affected lesion at the L2 and L3 vertebral bodies. All isolates from the surgical and needle biopsy specimens were identified as P. micra by 16S rRNA and MALDI-TOF. In this case, P. micra showed high sensitivity to antimicrobial therapy. She was successfully treated with debridement and sulbactam/ampicillin, followed by oral metronidazole for a total of 10 weeks. The causative microorganisms of spondylodiscitis are not often identified, especially anaerobic bacteria tend to be underestimated. On the other hand, antimicrobial therapy for spondylodiscitis is usually prolonged. Accordingly, we emphasize the importance of performing accurate identification including anaerobic bacteria.

A case of culture-negative endocarditis due to Streptococcus tigurinus.

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.