Keisuke Sunakawa

Kitasato University, Edo, Tōkyō, Japan

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Publications (322)247.4 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Streptococcus pneumoniae (S. pneumoniae) is a major causative pathogen of pneumonia in children. The Drug-Resistant Pathogen Surveillance Group in Pediatric Infectious Disease conducted nationwide surveillance of S. pneumoniae in 2000-2001, 2004, 2007, 2010 and 2012, and investigated changes in drug resistance of S. pneumoniae. All strains of S. pneumoniae were isolated from clinical specimens collected from pediatric patients. The minimum inhibitory concentration (MIC) was measured and the strains were classified according to the Clinical Laboratory Standards Institute (CLSI) criteria. The isolation rates of penicillin-intermediate resistant S. pneumoniae (PISP) and penicillin-resistant S. pneumoniae (PRSP) were compared based on 7 patient characteristic factors. Logistic regression analysis was also performed. The sum of the isolation rates for PISP and PRSP for each period was 64.6%, 67.0%, 56.2%, 76.9% and 49.5%, respectively. Among the patient characteristic factors, age category 1 (<3 years, ≥3 years), age category 2 (infant, toddler and preschooler, schoolchild), siblings (absence, presence), and pre-treatment with antimicrobial agents (absence, presence) were associated with significant differences in the isolation rates of PISP + PRSP. An interaction was observed between pre-treatment with antimicrobial agents and schoolchild, and the isolation rate of PISP + PRSP was higher in patients with both pre-treatment with antimicrobial agents and schoolchild. Though some changes were observed in the rate of resistance of S. pneumoniae, an increasing trend was not observed. Both pre-treatment with antimicrobial agents and age are resistant factors and an interaction was observed between pre-treatment with antimicrobial agents and schoolchild. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
    No preview · Article · Aug 2015 · Pediatrics International
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    ABSTRACT: Chemical compounds: Amphotericin B Deoxycholate (PubChem CID:23668620); amphotericin B (PubChem CID:5280965); 3-nitrophenol (PubChem CID:11137); methanol (PubChem CID:887).
    No preview · Article · Aug 2015 · Drug Metabolism and Pharmacokinetics
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    ABSTRACT: To investigate antimicrobial susceptibility patterns of various bacterial pathogens isolated from complicated urinary tract infection (UTI) cases, the Japanese Society of Chemotherapy, the Japanese Association of Infectious Disease, and the Japanese Society of Clinical Microbiology conducted the second nationwide surveillance from January to September 2011. With the cooperation of 42 medical institutions throughout Japan, 1036 strains belonging to 8 clinically relevant bacterial species were collected. Among methicillin-resistant Staphylococcus aureus (MRSA) strain, the vancomycin (VCM) MIC for 5.5% (3/55) of the strains was 2 μg/mL. Ampicillin, VCM, and linezolid were relatively active against 209 Enterococcus faecalis strains. The proportion of fluoroquinolone (FQ)-resistant strains was >20%. The MIC90 of FQs against the 382 Escherichia coli strains was 2-64 mg/L and the proportion resistant to FQs was approximately 30%. However, susceptibility of E. coli to sitafloxacin was still high (MIC90 = 2 mg/L). Fifty-eight (15.2%) of 382 E. coli, 6 (4.5%) of 132 Klebsiella pneumoniae, 1 (2.4%) of 41 Klebsiella oxytoca and 4 (6.8%) of 59 Proteus mirabilis strains were suspected of producing extended-spectrum beta-lactamase. Of 93 Pseudomonas aeruginosa strains, the proportions resistant to imipenem, amikacin, and ciprofloxacin were 21.5%, 4.3%, and 20.4%, respectively. Four strains (4.3%) were found to be multidrug-resistant. In complicated UTI cases, all of MRSA and E. faecalis were susceptible to all anti-MRSA agents. Sitafloxacin was active against other FQ-resistant E. coli strains. The isolation of extended-spectrum beta-lactamase-producing and multidrug-resistant strains increased. Copyright © 2015. Published by Elsevier Ltd.
    Full-text · Article · Jun 2015 · Journal of Infection and Chemotherapy
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    ABSTRACT: The nationwide surveillance on antimicrobial susceptibility of bacterial respiratory pathogens from patients in Japan, was conducted by Japanese Society of Chemotherapy, Japanese Association for Infectious Diseases and Japanese Society for Clinical Microbiology in 2010.The isolates were collected from clinical specimens obtained from well-diagnosed adult patients with respiratory tract infections during the period from January and April 2010 by three societies. Antimicrobial susceptibility testing was conducted at the central reference laboratory according to the method recommended by Clinical and Laboratory Standard Institutes using maximum 45 antibacterial agents.Susceptibility testing was evaluable with 954 strains (206 Staphylococcus aureus, 189 Streptococcus pneumoniae, 4 Streptococcus pyogenes, 182 Haemophilus influenzae, 74 Moraxella catarrhalis, 139 Klebsiella pneumoniae and 160 Pseudomonas aeruginosa). Ratio of methicillin-resistant S.aureus was as high as 50.5%, and those of penicillin-intermediate and -resistant S.pneumoniae were 1.1% and 0.0%, respectively. Among H.influenzae, 17.6% of them were found to be β-lactamase-non-producing ampicillin (ABPC)-intermediately resistant, 33.5% to be β-lactamase-non-producing ABPC-resistant and 11.0% to be β-lactamase-producing ABPC-resistant strains. Extended spectrum β-lactamase-producing K.pneumoniae and multi-drug resistant P.aeruginosa with metallo β-lactamase were 2.9% and 0.6%, respectively.Continuous national surveillance of antimicrobial susceptibility of respiratory pathogens is crucial in order to monitor changing patterns of susceptibility and to be able to update treatment recommendations on a regular basis. © 2015 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases.
    No preview · Article · May 2015 · Journal of Infection and Chemotherapy
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    ABSTRACT: The Japanese Three Academic Societies Joint Antimicrobial Susceptibility Surveillance Committee has conducted a nationwide surveillance on antimicrobial susceptibility patterns and rates of isolation in 6 otolaryngological diseases. The surveillance program was conducted in the otorhinolaryngological departments of 29 universities, and their 26 affiliated hospitals. Patients suffering from acute otitis media, chronic otitis media, acute nasal sinusitis, chronic nasal sinusitis, acute tonsillitis, and peritonsillar abscess between January 2011 and June 2012 were investigated. The collected swab or incision samples were cultivated for microbial identification, and the drug susceptibility of 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 (Peptostreptococcus spp., Prevotella spp., and Fusobacterium spp.). Bacterial susceptibility to 39 antimicrobial drugs was investigated. We compared bacterial isolation ratio of each disease in this surveillance from those of past 4 times surveillance which we performed formerly, and we also compared percentage of main drug resistant strains from those of past 4 times surveillance. The age composition between this time and former surveillances was not statistically significant by student -t test.
    Preview · Article · Mar 2015 · Journal of Infection and Chemotherapy
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    ABSTRACT: Based on the results of surveillance in the pediatric field conducted in 2007, 2010, and 2012, we examined the frequency of Haemophilus influenzae serotype b (Hib) strains, the susceptibility for Hib strains to various types of antimicrobial agent, and the relations to patients’ background factors.
    No preview · Article · Dec 2014 · Journal of Infection and Chemotherapy
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    ABSTRACT: The Drug-Resistant Pathogen Surveillance Group in Pediatric Infectious Disease has conducted surveillance of pediatric patients with respiratory tract infections, meningitis, and sepsis five times (in 2000-2001 [period 1], 2004 [period 2], 2007 [period 3], 2010 [period 4], and 2012 [period 5]). With respect to the clinically isolated Haemophilus influenzae (H. influenzae), the drug susceptibility, the frequency of drug-resistant strains, and patients’ background factors in each period have already been reported. Here we evaluate trends in the development of drug resistance in H. influenzae, and the relationship between the development of drug resistance and patients’ background factors in the aforementioned five periods.
    No preview · Article · Dec 2014 · Journal of Infection and Chemotherapy
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    ABSTRACT: During the surveillance conducted in 2012 by the Drug-resistant Pathogen Surveillance Group in Pediatric Infectious Disease, we isolated a strain of Moraxella catarrhalis that demonstrated resistance to both macrolides and quinolones from a male pediatric patient aged 1.5 years who had developed acute bronchitis. Then we evaluated the susceptibility of this strain to different types of antibacterial agents and conducted a genetic analysis.The results of the susceptibility evaluation showed that the MIC values of azithromycin, clarithromycin, and rokitamycin were >64 μg/mL, >64 μg/mL, and 4 μg/mL, respectively; clearly demonstrating resistance to macrolides. The MIC values of the quinolones levofloxacin, tosufloxacin, and garenoxacin were 4 μg/mL, 2 μg/mL, and 1 μg/mL, respectively; indicating decreased susceptibility. The genetic analysis of this strain revealed one mutation in 23s rRNA with a replacement of adenine by thymine at nucleotide position 2330 (A2330T) and another mutation in gyrB at nucleotide position 1481 by replacement of adenine with guanine (A1481G) that caused a substitution of the 494th asparagine acid by glycine, as being associated with the observed resistance to macrolides and quinolones, respectively.Similar to drug-resistant bacteria Streptococcus pneumoniae and Haemophilus influenzae, the prevalence of which has recently increased, the treatment of drug-resistant M. catarrhalis infections is considered difficult due to the development of resistance to different types of antibacterial agents. It is vital to maintain an unwavering focus on the trend toward an increasing number of drug-resistant M. catarrhalis strains and ensure the proper use of each antibacterial agent.
    No preview · Article · Nov 2014 · Journal of Infection and Chemotherapy
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    ABSTRACT: Key Clinical Message We report here a very rare case of primary meningococcal arthritis of the knee joint without clinical features associated with meningococcemia, meningitis, or meningococcal complications. The patient suffered from diabetes mellitus and had experienced two episodes of joint trauma. Intravenous infusion of ampicillin/sulbactam for 18 consecutive days was successful.
    Full-text · Article · Sep 2014
  • H. Sakata · S. Iwata · K. Ouchi · Y. Sato · N. Tsumura · K. Sunakawa
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    ABSTRACT: The purpose of this study was to assess the efficacy and safety of tosufloxacin tosilate hydrate fine granules (TFLX fine granules) for pediatric patients and to evaluate the position of TFLX fine granules in the treatment of community-acquired pneumonia (CAP) in children. The study was conducted in patients with CAP younger than 16 years of age who visited one of the 15 institutions between August 2010 and December 2012. The severity of infection was classified according to the severity assessment criteria in the Guidelines for the Management of Respiratory Infectious Diseases in Children in Japan 2007 (GL2007). We also examined the Guidelines for Management of Respiratory Infectious Diseases in Children in Japan 2011(GL2011), which were issued during the study, since the method for evaluation of the severity has greatly changed. The clinical efficacy, safety, and compliance of TFLX fine granules were evaluated based on the Criteria for Clinical Evaluation of Antibiotics in Pediatrics. A total of 104 patients were enrolled in the study. Of these patients, 102 were included in the safety analysis and 95 were included in the efficacy analysis. The overall efficacy rate was 94.7% (90/95) in patients with CAP, 97.7% (43/44) in patients with bacterial pneumonia, and 96.3% (26/27) in patients with mycoplasma pneumonia. The efficacy rate was 94.5% (69/73) in patients suspected of having antibiotic-resistant bacterial infections at the initial treatment and 100% (15/15) in patients with mycoplasma pneumonia who were suspected of having macrolide-resistant Mycoplasma pneumoniae infection. By the severity of infection based on the GL2007, the efficacy rate was 96.2% (25/26) in mild cases, 90.0% (27/30) in moderate cases, and 97.4% (38/39) in severe cases of pneumonia. Based on the GL2011, the efficacy rate was 97.7% (43/44) in mild, 92.2% (47/51) in moderate cases of pneumonia. The incidence of adverse drug reactions was 8.8% (9/102): diarrhoea (6.9%, 7/102) and abnormal laboratory values (2.0%, 2/102). No joint-related adverse drug reactions were noted. Overall, TFLX fine granules showed good efficacy and safety in children with CAP.
    No preview · Article · Sep 2014 · Japanese Journal of Chemotherapy
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    ABSTRACT: We conducted an antibiotic susceptibility survey of 830 blood-borne methicillin resistant Staphylococcus aureus collected from nationwide hospitals in Japan over a three-year period from January 2008 through May 2011. Antibiotic susceptibility was judged according to the criteria recommended by the Clinical Laboratory Standard Institute. Over 99% of the MRSA showed to be susceptible to teicoplanin, linezolid, sulfamethoxazole/trimethoprim and vancomycin, and over 97% of them were susceptible to daptomycin, arbekacin and rifampin. The majority of the MRSA strains showed resistant to minocycline, meropenem, imipenem, clindamycin, ciprofloxacin, cefoxitin, and oxacillin in the rates of 56.6, 72.9, 73.7, 78.7, 89.0, 99.5, and 99.9%, respectively. Among the MRSA strains, 72 showed reduced susceptibility to vancomycin, including 8 strains (0.96%) of vancomycin-intermediate S. aureus (VISA), 54 (6.51%) of heterogeneous vancomycin-intermediate S. aureus (hVISA), and 55 (5.63%) of β-lactam antibiotics-induced vancomycin resistant S. aureus (BIVR). Unexpectedly, among the 54 hVISA and 55 BIVR, 45 isolates (83.3% and 81.8%, respectively) showed both hVISA and BIVR phenotypes. A new trend of vancomycin resistance found in this study was that VISA strains were still prevalent among the bacteremic specimens. The high rates of the hVISA/BIVR two-phenotypic vancomycin resistance, and the prevalence of VISA in the bloodborne MRSA call attention in the MRSA epidemiology in Japan.
    Full-text · Article · Jul 2014 · Journal of Infection and Chemotherapy
  • Kazunobu Ouchi · Keisuke Sunakawa
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    ABSTRACT: In November 2004, "Guidelines for the Management of Respiratory Infectious Diseases in Children in Japan" was published ahead of the rest of the world, by Japanese Society of Pediatric Pulmonology/Japanese Society for Pediatric Infectious Diseases, based on the data on causative organisms in the lower respiratory tract. In its 2011 version, classification of the severity of pneumonia was renewed based on the latest information. As a result, many types of pneumonia in children are now classified as mild or moderate. This means that many patients who might have conventionally required hospital treatment can now be managed on an outpatient basis. The reason for realization of the wider range of outpatient treatment is the availability of two new oral antimicrobial agents, tebipenem pivoxil and tosufloxacin tosilate hydrate, for the treatment of infections in children. Analysis of data on medical expenses shows a decreased rate of hospitalization due to pneumonia year by year after launch of these two drugs, suggesting that these drugs have contributed to wider range of outpatient treatment. This manuscript discusses the effect of tebipenem pivoxil and tosufloxacin tosilate hydrate in the treatment of pneumonia.
    No preview · Article · Jun 2014 · The Japanese journal of antibiotics
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    ABSTRACT: To investigate the trends in incidence and the characteristics of bacterial meningitis in Japan where Haemophilus influenzae type b (Hib) vaccine and 7-valent pneumococcal conjugated vaccine (PCV7) were introduced in 2008 and 2010, respectively, which was 5-20 years after their introduction in western countries. The nationwide Japanese survey of pediatric and neonatal bacterial meningitis was performed in 2011 and 2012. We analyzed the epidemiological and clinical data, and compared the information obtained in the previous nationwide survey database. We also investigated the risk factors for disease outcome. In the 2011-2012 surveys, 357 patients were evaluated. H. influenzae, Streptococcus pneumoniae, Streptococcus agalactiae and Escherichia coli were the main organisms. The number of patients hospitalized with bacterial meningitis per 1000 admissions decreased from 1.31 in 2009 to 0.43 in 2012 (p < 0.001). The incidence of H. influenzae and S. pneumoniae meningitis also decreased from 0.66 to 0.08 (p < 0.001), and 0.30 to 0.06 (p < 0.001), respectively. Only 0-2 cases with Neisseria meningitidis were reported each year throughout 2001-2012. The median patient age was 10-12 months in 2001-2011, and became lower in 2012 (2 month old) (p < 0.001). The fatality rate for S. agalactiae is the highest (5.9% (11/187)) throughout 2001-2012 among the four organisms. Risk factors for death and sequelae were convulsions at onset, low CSF glucose, S. agalactiae etiology, and persistent positive CSF culture. Hib vaccine and PCV7 decreased the rate of bacterial meningitis. Earlier introduction of these vaccines may have prevented bacterial meningitis among Japanese children.
    No preview · Article · May 2014 · Journal of Infection and Chemotherapy
  • S. Iwata · K. Suzuki · S. Takayama · K. Sunakawa
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    ABSTRACT: We conducted a postmarketing surveillance of tosufloxacin granules (OZEX® fine granules 15%), an oral quinolone antibacterial agent for children, between March 2010 and March 2011 to evaluate the safety, efficacy, and compliance in patients with bacterial pneumonia or otitis media. Of 808 patients enrolled, 797 from whom survey forms were collected were analyzed. Of these 797 patients, there were a total of 760 patients included in the compliance analysis, 759 in the safety analysis, 688 in the efficacy analysis, 100 in the clinical efficacy analysis by causative organism, and 20 in the bacteriological efficacy analysis. The incidence of adverse drug reactions (ADRs) was 2.77% (21/759), and the major ADRs were gastrointestinal disorders including diarrhea in 16 patients (2.11%). Nausea/vomiting and joint disorders were intensively investigated. Vomiting was reported in 8 patients (1.05%), which was not clinically significant. No joint disorders were reported. The overall efficacy rate was 98.1% (675/688). The efficacy rate by the type of infection was 100% (145/145) for bacterial pneumonia and 97.7% (506/518) for otitis media. The eradication rates of Streptococcus pneumoniae and Haemophilus influenzae which are major causative organisms in pediatric infections of pneumonia and otitis media were 7/8 and 93.3% (14/15), respectively. The compliance was good in 87.5% of the patients (665/760). Overall, OZEX® fine granules 15% showed good safety, efficacy, and compliance. These results indicate that OZEX® fine granules 15% is a useful agent in children with pneumonia or otitis media. We consider that we should maximize the value of OZEX® fine granules 15% with promotion of the proper use.
    No preview · Article · Mar 2014 · Japanese Journal of Chemotherapy
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    ABSTRACT: To investigate the trends in incidence and the characteristics of bacterial meningitis in Japan where Haemophilus influenzae type b (Hib) vaccine and 7-valent pneumococcal conjugated vaccine (PCV7) were introduced in 2008 and 2010, respectively, which was 5–20 years after their introduction in western countries. The nationwide Japanese survey of pediatric and neonatal bacterial meningitis was performed in 2011 and 2012. We analyzed the epidemiological and clinical data, and compared the information obtained in the previous nationwide survey database. We also investigated the risk factors for disease outcome. In the 2011–2012 surveys, 357 patients were evaluated. H. influenzae, Streptococcus pneumoniae, Streptococcus agalactiae and Escherichia coli were the main organisms. The number of patients hospitalized with bacterial meningitis per 1000 admissions decreased from 1.31 in 2009 to 0.43 in 2012 (p < 0.001). The incidence of H. influenzae and S. pneumoniae meningitis also decreased from 0.66 to 0.08 (p < 0.001), and 0.30 to 0.06 (p < 0.001), respectively. Only 0–2 cases with Neisseria meningitidis were reported each year throughout 2001–2012. The median patient age was 10–12 months in 2001–2011, and became lower in 2012 (2 month old) (p < 0.001). The fatality rate for S. agalactiae is the highest (5.9% (11/187)) throughout 2001–2012 among the four organisms. Risk factors for death and sequelae were convulsions at onset, low CSF glucose, S. agalactiae etiology, and persistent positive CSF culture. Hib vaccine and PCV7 decreased the rate of bacterial meningitis. Earlier introduction of these vaccines may have prevented bacterial meningitis among Japanese children.
    No preview · Article · Jan 2014
  • Y. Sato · Y. Toyonaga · H. Hanaki · K. Sunakawa
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    ABSTRACT: We investigated drug susceptibilities to various antimicrobial drugs of 370 isolates of Streptococcus pneumoniae, 411 of Haemophilus influenzae, and 111 of Moraxella catarrhalis, which were isolated from pediatric patients with respiratory tract infections (upper respiratory inflammation, bronchitis, and pneumonia), meningitis, or sepsis at 22 sites that participated in the Japanese nationwide Drug-Resistant Pathogen Surveillance Group in Pediatric Infectious Disease between January and June 2012. The frequency of resistant bacterium isolation and the patient's background factors were also examined. For S. pneumoniae, the isolation frequency of penicillin-susceptible S. pneumoniae (PSSP), penicillin-intermediate-resistant S. pneumoniae (PISP), and penicillin-resistant S. pneumoniae (PRSP) was 50.5%, 39.2%, and 10.3%, respectively. The isolation frequency of PISP + PRSP was 49.5%. The following drugs displayed an MIC90 of ≤1 μg/mL against PRSP: tebipenem (TBPM), faropenem (FRPM), cefditoren (CDTR), panipenem (PAPM), doripenem (DRPM), meropenem (MEPM), garenoxacin (GRNX), vancomycin (VCM), and tosufloxacin (TFLX). For H. influenzae, the isolation frequency of β-lactamase- nonproducing ABPC-susceptible H. influenzae (BLNAS), β-lactamase- nonproducing ABPC-intermediate-resistant H. influenzae (BLNAI), β-lactamase-nonproducing ABPC-resistant H. influenzae (BLNAR), β-lactamase-producing ABPC-resistant H. influenzae (BLPAR), and β-lactamase-producing CVA/AMPC-resistant H. influenzae (BLPACR) was 28.0%, 16.8%, 46.7%, 4.4%, and 4.1%, respectively. The isolation frequency of BLNAI + BLNAR was 63.5%. The following drugs displayed an MIC90 of ≤1 μg/mL against BLNAI + BLNAR and β-lactamase-producing bacteria: CDTR, cefteram (CFTM), TBPM, tazobactam/piperacillin (TAZ/PIPC), MEPM, ceftriaxone (CTRX), cefotaxime (CTX), GRNX, levofloxacin (LVFX), and TFLX. For M. catarrhalis, favorable susceptibility to the following drugs was noted: combinations of β-lactamase inhibitors and synthetic penicillins, third-generation cephems, carbapenems, macrolides, and quinolones. One strain, however, showed a low sensitivity to macrolides and quinolones. A significant difference in the isolation frequency of antimicrobial-resistant S. pneumoniae was found depending on the existence of previous antibacterial agent usage, and that of antimicrobial-resistant H. influenzae was found depending on the age category (younger than 3 years, 3 years or older) and the existence of siblings.
    No preview · Article · Jan 2014 · Japanese Journal of Chemotherapy
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    ABSTRACT: Secondary bacterial pneumonia due to community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has become a highly publicized cause of death associated with influenza. In this study, we performed the gentamicin-killing assay using Madin-Darby canine kidney (MDCK) cells and MRSA strains to investigate whether prior infection from pandemic A(H1N1)2009 virus (A[H1N1]pdm09) lead to increased invasion of MDCK cells by MRSA. We found that the invasion rate of two MRSA strains (ATCC BAA-1680 [USA 300] and ATCC BAA-1699 [USA 100]) into intact MDCK cell monolayers was 0.29 ± 0.15% and 0.007 ± 0.002%, respectively (p < 0.01, n ≥ 3). In addition, the relative invasion rate of both ATCC BAA-1680 and ATCC BAA-1699 was significantly increased by prior A(H1N1)pdm09 infection of MDCK monolayers from 1 ± 0.28 to 1.38 ± 0.02 and from 1 ± 0.24 to 1.73 ± 0.29, respectively (p < 0.01). These results indicate that ATCC BAA-1680 displays much stronger invasiveness of MDCK cells than ATCC BAA-1699, although invasion of both strains was increased by prior A(H1N1)pdm09 infection. In conclusion, this study provided the first evidence that prior A(H1N1)pdm09 infection facilitates the invasion of MDCK cells by MRSA, presumably due to cellular injury caused by the virus.
    No preview · Article · Dec 2013 · Journal of Infection and Chemotherapy
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    ABSTRACT: The population pharmacokinetics on tazobactam/piperacillin (TAZ/PIPC; 1:8, 4.5 g x 3) was analyzed in Japanese patients with community-acquired pneumonia using the Nonlinear Mixed Effect Model version VI. Analysis by the one-compartment model yielded the following results for PIPC: total clearance (CL) = 8.22+(Ccr-71.4) x 0.0561 (L/hr), distribution volume (Vd) = 13.7 (L). The pharmacokinetic parameters for TAZ were: CL = 8.67 + (Ccr-71.4) x 0.0682 (L/hr), Vd = 14.4 (L). Of the pharmacokinetic parameters of PIPC, CL included Ccr as a variation factor, whereas the Vd included no variation factor. Because PIPC is excreted into the urine in the unchanged form, its pharmacokinetic factors seem to reflect the renal function status. In this study of patients with community-acquired pneumonia, the mean Vd per body weight was 0.26 L/kg, and the results suggested an increase of the Vd in patients with community-acquired pneumonia as compared with the value in healthy adults.
    No preview · Article · Aug 2013 · The Japanese journal of antibiotics
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    ABSTRACT: Group B Streptococcus (GBS, Streptococcus agalactiae) is a leading cause of serious neonatal infections. Center for Disease Control and Prevention recommends GBS screening for all pregnant women during the 35th to 37th week of gestation. Although GBS screening has been performed mainly by the culture-based method, it takes several days to obtain a reliable result. In this study, we developed a rapid immunochromatographic test (ICT) for the detection of GBS-specific surface immunogenic protein in 15 min using an overnight enrichment culture. The ICT was prepared using two anti-Sip monoclonal antibodies. This ICT was able to detect recombinant Sip levels 0.5 ng/ml, or about 10(6) CFU/ml of GBS cells, in tests with 9 GBS strains of different serotypes. The cross reactivity test using 26 species of microorganism showed no detectable false positive result. Reactivity of the ICT with 229 GBS strains showed one false negative result that was attributable to the production of truncated Sip. Among 260 enrichment cultures of vaginal swabs, 17 produced red to orange pigments in the Granada medium and they were all GBS- and Sip-positives. Among 219 pigment-negative cultures, 12 were GBS-positive and 10 were Sip-positive. Sip-negative two cultures contained GBS cells below the limit of detection by the ICT. Among 207 GBS-negative cultures, only one was Sip-positive, which was attributable to GBS cell debris. Thus, the sensitivity and specificity of the ICT appeared 93.1% and 99.6%, respectively. The newly developed ICT is readily applicable to clinical use in the detection of GBS.
    Full-text · Article · Jul 2013 · Clinical and vaccine Immunology: CVI
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    ABSTRACT: Worldwide, the most important concern in the treatment of sexually transmitted infections is the increase in antimicrobial resistant Neisseria gonorrhoeae strains including resistance to cephalosporins, penicillins, fluoroquinolones or macrolides. To investigate the trends of antimicrobial susceptibility among N. gonorrhoeae strains isolated from male patients with urethritis, a Japanese surveillance committee conducted the second nationwide surveillance study. Urethral discharge was collected from male patients with urethritis at 26 medical facilities from March 2012 to January 2013. Of the 151 specimens, 103 N. gonorrhoeae strains were tested for susceptibility to 20 antimicrobial agents. None of the strains was resistant to ceftriaxone, but the minimum inhibitory concentration (MIC) 90% of ceftriaxone increased to 0.125 μg/ml, and 11 (10.7%) strains were considered less susceptible with an MIC of 0.125 μg/ml. There were 11 strains resistant to cefixime, and the MICs of these strains were 0.5 μg/ml. The distributions of the MICs of fluoroquinolones, such as ciprofloxacin, levofloxacin and tosufloxacin, were bimodal. Sitafloxacin, a fluoroquinolone, showed strong activity against all strains, including strains resistant to other three fluoroquinolones, such as ciprofloxacin, levofloxacin and tosufloxacin. The azithromycin MICs in 2 strains were 1 μg/ml. Copyright © 2015 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.
    Full-text · Article · Jun 2013 · Journal of Infection and Chemotherapy

Publication Stats

2k Citations
247.40 Total Impact Points

Institutions

  • 2001-2014
    • Kitasato University
      • • Department of Infectious Diseases
      • • Graduate School of Infection Control Sciences
      • • Medical Department
      Edo, Tōkyō, Japan
  • 2011
    • Kawasaki Medical University
      • Department of Pediatrics
      Kurasiki, Okayama, Japan
  • 2007
    • Nho Tokyo Medical Center
      Edo, Tōkyō, Japan
  • 2003-2007
    • Kyorin University
      • School of Health Sciences
      Japan
  • 2004
    • The University of Tokyo
      • Department of Health Science and Nursing
      Tokyo, Tokyo-to, Japan
  • 1996
    • Kawasaki Municipal Hospital
      Kawasaki Si, Kanagawa, Japan
  • 1992-1995
    • Teikyo University
      • Department of Medicine
      Tokyo, Tokyo-to, Japan
  • 1979-1994
    • Keio University
      • • Department of Pediatrics
      • • Department of Pathology
      Edo, Tokyo, Japan