Maki Nagamatsu

Neonatal meningitis caused by Streptococcus gallolyticus subsp. pasteurianus

We encountered a case of neonatal meningitis caused by Streptococcus gallolyticus subsp. pasteurianus. The patient was an 8-day-old boy. Gram staining of the cerebrospinal fluid (CSF) revealed gram-positive cocci in pairs or in short chains. In culture, γ-streptococcus-like colonies grew. The result of 16S rRNA sequence analysis identified S. gallolyticus subsp. pasteurianus. From these results, bacterial meningitis was diagnosed and, as a result of antimicrobial susceptibility testing, single-dose ampicillin therapy was given. Because inflammatory deterioration and spread was suspected from the CSF test results, this therapy was added by panipenem/betamipron. In response to his recovery, antibiotic treatment was stopped and the boy was discharged. This bacterium was classified as S. gallolyticus subsp. pasteurianus in the latest report in 2003. Since this change, there have only been a few cases of neonatal meningitis caused by this bacterium. Here we report this rare case.

Multidrug-resistant Acinetobactor baumannii isolated from a traveler returned from Brunei

We report a case of multidrug-resistant (MDR) Acinetobactor baumannii isolates obtained from a traveler returned from Brunei. Whole-genome sequencing analysis revealed that the isolates harbored blaOxA-23 and armA. The minimum inhibitory concentrations of antibiotics against the strain were as follows: imipenem, 32 μg/ml; meropenem, 32 μg/ml; ciprofloxacin, 16 μg/ml; amikacin, ≧ 1024 μg/ml; arbekacin, ≧ 1024 μg/ml; aztreonam, 64 μg/ml; colistin, 4 μg/ml. A. baumannii harboring both blaOxA-23 and armA is rarely reported in Japan, and, to the best of our knowledge, this is the second report of A. baumannii harboring both resistant genes in Japan.

Impact of rapid identification of positive blood cultures using the Verigene system on antibiotic prescriptions: A prospective study of community-onset bacteremia in a tertiary hospital in Japan

Background Rapid identification of positive blood cultures is important for initiation of optimal treatment in septic patients. Effects of automated, microarray-based rapid identification systems on antibiotic prescription against community-onset bacteremia (COB) remain unclear. Methods We prospectively enrolled 177 patients with 185 COB episodes (occurring within 72 h of admission) over 17 months. Bacteremia episodes due to gram-positive bacteria (GP) and gram-negative bacteria (GN) in the same patient were counted separately. For GP bacteremia, patients with ≥2 sets of positive blood cultures were included. The primary study objective was evaluating the rates of antibiotic prescription changes within 2 days of rapid identification using the Verigene system. Results Bacteremia due to GN and GP included 144/185 (77.8%) and 41/185 (22.2%) episodes, respectively. Antibiotic prescription changes occurred in 51/185 cases (27.6% [95%CI:21.3–34.6%]) after Verigene analysis and 70/185 cases (37.8% [30.8–45.2%]) after conventional identification and susceptibility testing. Prescription changes after Verigene identification were more frequent in GP (17/41[41.5%]) than in GN (34/144[23.5%]). Among bacteremia due to single pathogen targeted by Verigene test, bacterial identification agreement between the two tests was high (GP: 38/39[97.4%], GN: 116/116[100%]). The Verigene test correctly predicted targeted antimicrobial resistance. The durations between the initiation of incubation and reporting of the results for the Verigene system and conventional test was 28.3 h (IQR: 25.8–43.4 h) and 90.6 h (68.3–118.4 h), respectively. In only four of the seven episodes of COB in which two isolates were identified by conventional tests, the Verigene test correctly identified both organisms. Conclusion We observed a high rate of antibiotic prescription changes after the Verigene test in a population with COB especially in GP. The Verigene test would be a useful tool in antimicrobial stewardship programs among patients with COB.

Epidemiology of extended-spectrum beta-lactamase (ESBL) producing Escherichia coli in Japan: Characteristics of community-associated versus healthcare-associated ESBL E. coli

Data on community-associated extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli (CA-ESBLEC) infections in Japan are scarce. We compared the clinical and microbiological epidemiology of CA-ESBLEC infections with that of healthcare-associated-ESBLEC infections among 76 patients with ESBLEC infections. We identified a high prevalence (26%) of CA-ESBLEC infections in Japan; only a small proportion (15%) of patients with CA-ESBLEC infections had recent exposure to antibiotics.

Two Cases of Granulomatous Mastitis Caused by Corynebacterium kroppenstedtii Infection in Nulliparous Young Women with Hyperprolactinemia.

Recently, an association between granulomatous mastitis and local infection with Corynebacterium (C.) kroppenstedtii has been suggested. We herein report two cases of granulomatous mastitis resulting from C. kroppenstedtii infection in nulliparous young women with hyperprolactinemia. Both cases involved nulliparous patients with drug-induced hyperprolactinemia, and both individuals received incision and drainage, after which the pus was sent to our laboratory. Corynebacterium spp. grew on blood agar, and 16S rRNA gene sequencing identified the pathogen as C. kroppenstedtii. In conclusion, lactational changes caused by drug-induced hyperprolactinemia may increase the risk of granulomatous mastitis after C. kroppenstedtii infection.

Successful treatment of recurrent Helicobacter fennelliae bacteraemia by selective digestive decontamination with kanamycin in a lung cancer patient receiving chemotherapy

Introduction: Helicobacter fennelliae is an enterohepatic Helicobacter species causing bacteraemia in immunocompromised hosts. Only a few cases of recurrent H. fennelliae bacteraemia have been reported in Japan and there are no guidelines regarding antimicrobial treatment for H. fennelliae infection. Case presentation: H. fennelliae bacteraemia was observed in a patient receiving platinum-based chemotherapy for lung cancer. To prevent recurrence, the patient received antibiotic therapy with cefepime, amoxicillin and doxycycline for 6 weeks, which is similar to the therapy for Helicobacter cinaedi bacteraemia. Bacteraemia recurred despite the long-term antibiotic therapy. We hypothesized that the H. fennelliae bacteraemia originated from endogenous infection in the intestinal tract due to the long-term damage of the enteric mucosa by platinum-based drugs and performed selective digestive decontamination (SDD) with kanamycin. Bacteraemia did not recur after SDD. Conclusion: Our observations indicate that clinicians should be aware of possible recurrent H. fennelliae bacteraemia, which could be effectively prevented by SDD with kanamycin.

Comparative Genome Analysis of Extended-Spectrum-β-Lactamase-Producing Escherichia coli Sequence Type 131 Strains from Nepal and Japan.

The global spread of ESBL-E. coli has been driven in large part by pandemic sequence type 131 (ST131). A recent study suggested that, within E. coli ST131, certain sublineages have disseminated worldwide with little association with their geographical origin, highlighting the complexity of the epidemiology of this pandemic clone. ST131 bacteria have also been classified into four virotypes based on the distribution of certain virulence genes. Information on virotype distribution in Asian ST131 strains is limited. We conducted whole-genome sequencing of ESBL-E. coli ST131 strains collected in Nepal and Japan, two Asian countries with a high and low prevalence of ESBL-E. coli, respectively. We systematically compared these ST131 genomes with those reported from other regions to gain insights into the molecular epidemiology of their spread and found the distinct phylogenetic characteristics of the spread of ESBL-E. coli ST131 in these two geographical areas of Asia. ABSTRACT The global spread of extended-spectrum-β-lactamase (ESBL)-producing Escherichia coli (ESBL-E. coli) has largely been driven by the pandemic sequence type 131 (ST131). This study aimed to determine the molecular epidemiology of their spread in two Asian countries with contrasting prevalence. We conducted whole-genome sequencing (WGS) of ESBL-E. coli ST131 strains collected prospectively from Nepal and Japan, two countries in Asia with a high and low prevalence of ESBL-E. coli, respectively. We also systematically compared these genomes with those reported from other regions using publicly available WGS data for E. coli ST131 strains. Further, we conducted phylogenetic analysis of these isolates and all genome sequence data for ST131 strains to determine sequence diversity. One hundred five unique ESBL-E. coli isolates from Nepal (February 2013 to July 2013) and 76 isolates from Japan (October 2013 to September 2014) were included. Of these isolates, 54 (51%) isolates from Nepal and 11 (14%) isolates from Japan were identified as ST131 by WGS. Phylogenetic analysis based on WGS suggested that the majority of ESBL-E. coli ST131 isolates from Nepal clustered together, whereas those from Japan were more diverse. Half of the ESBL-E. coli ST131 isolates from Japan belonged to virotype C, whereas half of the isolates from Nepal belonged to a virotype other than virotype A, B, C, D, or E (A/B/C/D/E). The dominant sublineage of E. coli ST131 was H30Rx, which was most prominent in ESBL-E. coli ST131 isolates from Nepal. Our results revealed distinct phylogenetic characteristics of ESBL-E. coli ST131 spread in the two geographical areas of Asia, indicating the involvement of multiple factors in its local spread in each region. IMPORTANCE The global spread of ESBL-E. coli has been driven in large part by pandemic sequence type 131 (ST131). A recent study suggested that, within E. coli ST131, certain sublineages have disseminated worldwide with little association with their geographical origin, highlighting the complexity of the epidemiology of this pandemic clone. ST131 bacteria have also been classified into four virotypes based on the distribution of certain virulence genes. Information on virotype distribution in Asian ST131 strains is limited. We conducted whole-genome sequencing of ESBL-E. coli ST131 strains collected in Nepal and Japan, two Asian countries with a high and low prevalence of ESBL-E. coli, respectively. We systematically compared these ST131 genomes with those reported from other regions to gain insights into the molecular epidemiology of their spread and found the distinct phylogenetic characteristics of the spread of ESBL-E. coli ST131 in these two geographical areas of Asia.

Molecular and Clinical Epidemiology of Salmonella Paratyphi A Isolated from Patients with Bacteremia in Nepal

Little is known about the epidemiology of typhoid and paratyphoid fever in Nepal. We aimed to elucidate the molecular and clinical epidemiology of Salmonella Paratyphi A in Nepal. Isolates were collected from 23 cases of bacteremia due to S. Paratyphi A between December 2014 and October 2015. Thirteen patients (57%) were male, and the median age was 21 years. None of the patients had an underlying chronic disease. All S. Paratyphi A isolates were sensitive to ampicillin, trimethoprim/sulfamethoxazole, ceftriaxone, and chloramphenicol. All isolates were resistant to nalidixic acid and were categorized as intermediately susceptible to levofloxacin. Phylogenetic analysis revealed close relatedness among the isolates, including several clonal groups, suggesting local spread. Patients with bacteremia due to S. Paratyphi A in Kathmandu, Nepal, were relatively young and nondebilitated. Improving control of S. Paratyphi infections should focus on effective infection control measures and selection of empirical therapy based on current resistance patterns.

Use of polymerase chain reaction in the diagnosis of Whipple's disease.

Whipples disease, a systemic, chronic infectious disease caused by Tropheryma whipplei, is extremely rare in Asian populations. A correct diagnosis is necessary due to its high mortality rate. Unfortunately, patients are apt to be misdiagnosed with connective tissue diseases since they typically present with arthritis or arthralgia. There are three diagnostic tools for Whipples disease using intestinal tissues: 1) periodic acid-Schiff (PAS)-positive macrophages; 2) electron microscopic observation; and 3) polymerase chain reaction (PCR). It is challenging to diagnose this disease in the absence of histological findings, especially in Japan, where the clinical protocol currently used to make the diagnosis needs improvement, although symptomology and PCR results may be sufficient. Herein, we investigated a 24-year-old Japanese woman who had suffered from intermittent fever, migratory arthralgia, and watery diarrhea for several months. Her biopsied intestinal tissue was negative for foamy macrophages and PAS-positive cells, and electron microscopy did not provide diagnostic insight. PCR amplification of the specimens, however, successfully revealed T. whipplei. Whipples disease was diagnosed based on a positive PCR result and strong clinical suspicion. The patient was treated parenterally with ceftriaxone (2 g daily) for two weeks, followed by oral treatment with 160 mg trimethoprim and 800 mg sulfamethoxazole twice per day. After one month of treatment, her symptoms disappeared and inflammatory markers returned to normal levels. This case illustrates the practicality and effectiveness of a PCR-based diagnostic test in combination with clinical suspicion to correctly diagnose Whipples disease, especially in cases when a histological examination does not provide insight.

Correction for Miyoshi-Akiyama et al., “Comparative Genome Analysis of Extended-Spectrum-β-Lactamase-Producing Escherichia coli Sequence Type 131 Strains from Nepal and Japan”

[This corrects the article DOI: 10.1128/mSphere.00289-16.].