We examined staphylococcal coagulase types and homologous analysis using the Diversi Lab repetitive sequence-based PCR system in exfoliative toxin (ET)-producing Staphylococcus aureus.Twenty-two isolates (17 methicillin-sensitive Staphylococcus aureus (MSSA) and 5 methicillin-resistant Staphylococcus aureus (MRSA) isolates) obtained in our hospital from January 2012 and December 2013 were used. Three groups were classified according to the coagulase types and serotypes of ET. The first group (4 MSSA) showed coagulase type I and ET-A, and the second group (3 MSSA and 2 MRSA) showed coagulase type I and ET-B. The third group (10 MSSA and 3 MRSA) showed coagulase type V and ET-B. An analysis by Divers iLab demonstrated that homology was high in both the first and second groups. The homogenousness was high among the third group isolates except for the ocular isolates. In our hospital, three important groups were present according to a coagulase type and an ET type, and the homology of ocular isolates could be different from other materials isolates.

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Detection of Streptococcus pneumoniae colonized in the pharynx of healthy carriers currently relies on conventional culture methods of direct plating with pharyngeal swab specimens. The accurate measurement of the carriage of pneumococci, however, has not been necessarily achieved with these methods due to low density colonization and contamination of numerous oral streptococci that express α-hemolysis. A PCR-based detection method of pneumococci-specific for lytA as well as PCR serotyping of S. pneumoniae was recently developed and their effectiveness was confirmed. We modified the reaction conditions of these methods to improve the detection rate and applied them to the measurement of S. pneumoniae carried in healthy adults. Pharyngeal swab specimens obtained from 110 healthy volunteers over 40 and living in Nagoya were enriched for 5 hours with broth medium supplemented with rabbit serum and the template DNA for PCR was extracted from the mixed enriched culture. Of 110 specimens 36 (32.7％) were lytA-positive, the rate of which was much higher than the results of previous culture-based studies. The DNA template preparations were then used for PCR-based serotyping with primers specific for each of the types included in pneumococcal 23 valent vaccine (PPV23). We found that 28 out of 36 lytA-positive carriers were identified as being positive for the serotypes belonging to PPV23, although serotypes 6A and 6B were indistinguishable with the PCR method. The most frequent serotype was serotype 14, and serotypes 4, 18C, and 6A/B were also frequently identified. Five lytA-positive carriers were previously vaccinated with PPV23, and among them, 4 were positive for serotypes contained in PPV23. We recommend PCR-based identification and serotyping of S. pneumoniae in broth enrichment culture of pharyngeal swab specimens as a reliable method for the surveillance of healthy carriers with low density colonization.

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In the 2011/2012 season, 18 patients were admitted to our hospital due to influenza virus A infection and the number had increased compared to the previous 3 years (average 5.3 patients/year). Therefore we evaluated the clinical characteristics, treatment, and prognosis of hospitalized cases. Although there were many reports on viral pneumonia caused by influenza (H1N1) 2009 among the young population in the 2009/2010 season, 16 out of 18 hospitalized patients were over 65 years-old in the 2011/2012 season. Major causes of admission were pneumonia in 8 cases, heart failure in 5 cases and bronchial asthma attack in 3 cases. The average age of 9 patients with pneumonia was higher significantly compared to 9 patients without pneumonia (average age 85.3 ± 10.2：71.4 ± 16.1, p ＜0.05). Influenza vaccination was performed in 11 patients in total, and 6 out of 9 patients with pneumonia. The interval from illness onset to administration of neuraminidase inhibitors was 1.8 ± 1.1 days in cases with pneumonia and 2.1 ± 1.5 days in cases without pneumonia. Though 17 patients got well, one patient died from aspiration pneumonia after recovering from influenza A infection. In the 2011/2012 season, although many patients who had received vaccination needed to be hospitalized because of influenza A infection, the prognosis was fairly good.

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Object：It appears to be possible to measure the outbreak of infectious diseases with accompanying diarrhea by early detection of an outbreak. However, because some diseases are reported weekly from sentinel medical institutions, early detection of outbreaks might be inadequate. In this study, we examined the number of patients with diarrhea assessed with prescription surveillance and validated its association with the number of patients who have infectious diseases with diarrhea. Methods：The number of patients who were prescribed an antidiarrheal drug or intestinal drug was estimated for each prefecture using the prescription surveillance system from April 1, 2011 through March 31, 2014. Moreover, we examined the association between the prevalence of diarrhea in prescription surveillance and the number of patients with diarrheal infectious diseases. Results：Results showed a positive correlation between the prevalence of diarrhea in prescription surveillance and the number of reported cases per sentinel with gastrointestinal infections. However, no positive correlation was found with the others infectious diseases. Conclusion：Estimation of the number of patients with diarrhea in prescription surveillance might facilitate early detection of an outbreak of gastrointestinal infections.

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We evaluated the usefulness of a rapid antigen detection assay for L7/L12 ribosomal protein (Ribotest Mycoplasma ; Asahi Kasei Pharma) for diagnosis of Mycoplasma pneumoniae (M. pneumoniae) infection. Nasopharyngeal swabs were obtained from patients with pneumonia and/or bronchitis ; real-time PCR and the L 7/L12 antigen assays were performed with each sample. Serum was also taken from each patient, and the particle agglutination (PA) method was used to detect anti―M. pneumoniae antibody in these samples. Macrolide-resistance genes were detected and M. pneumoniae P1 protein subtyping was performed on PCR positive samples. PCR assays were positive for 85 of 212 specimens (40.1％). Sensitivity and specificity of the L7/L12 antigen assays relative to the PCR standard were 74.1％(63/85) and 81.1％(103/127), respectively. For PCR-positive specimens with a large quantity of M. pneumoniae nucleic acid, sensitivity of the L7/L12 antigen assays seemed to be high. In PCR-positive specimens with fewer than1.0×10⁶ copies/mL of M. pneumoniae nucleic acid, sensitivity of the L7/L12 antigen assays seemed to be low. When the PA method was used as the standard, the relative sensitivity and specificity of the L7/L12 antigen assays were 41.7％(5/12) and 75.3％(58/77), respectively, for single serum and 60.9％(14/23) and 85.7％(18/21), respectively, for paired sera. The macrolide-resistance gene A2063G was detected in 20 of the 30 tested PCR-positive specimens (66.7％). Of these 20 A2063G-positive specimens, 13（65.0％）were positive for the L7/L12 antigen assays. Tne numbers of M. pneumoniae P1 subtypes were as follows : types I (22), IIa(2), IIc(1), and untypable (5). The L7/L12 antigen assays gave positive results for 17 of 21（81.0％) subtype I, 1 of 2 (50.0％) IIa, and 1 of 1(100％) IIc specimens.

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We report herein on a case of invasive aspergillosis accompanied by a subcutaneous nodular lesion. A 74-years-old male with myelodysplastic syndrome was hospitalized due to high fever and a painful subcutaneous nodule on the left thigh. Chest radiography and CT scans showed multiple nodular lesions of both lungs, and bacterial pneumonia was initially suspected. He was treated with meropenem, but the symptoms did not subside. Three days after admission, we found that β-D-glucan levels were elevated at 52.6pg/mL. He was treated with liposomal amphotericin B (L-AMB) for invasive fungal pneumonia, and the symptoms regressed thereafter. Excisional biopsy of the nodular lesion showed a cluster of septated and branching hyphae. Serum Aspergillus antigen tests and sputum fungal culture were negative, and the fungal species could not be identified. Thus, we performed in situ hybridization (ISH) and polymerase chain reaction (PCR) with the excised subcutaneous specimens, and as a result, Aspergillus fumigatus infection was diagnosed. Invasive aspergillosis with a subcutaneous lesion is a rare case, and we found that treatment with L-AMB was effective. ISH, PCR and measurement of serum trough concentration of AMPH-B are useful in diagnosis and treatment.

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We report herein on a 71-year-old man who developed pseudomembranous colitis (PMC). He was treated with oral metronidazole and vancomycin prescription, but deteriorated, and developed a toxic megacolon. Under paralytic ileus condition, per os and enema treatment efficacy was thought to be limited. Sprinkling with vancomycin via colonoscopy was therefore performed, resulting in therapeutic success. Additionally, participation in infection control should be carried out with severe PMC cases like this.

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A 54-year-old female with dermatomyositis treated with cyclosporine and methylprednisolone presented with multiple subcutaneous nodules on her upper and lower extremities on December 2011. The number of lesions gradually increased. She had a history of surgical intervention such as debridement, skin graft of right lower leg due to trauma and subsequent bacterial infection on August 2011. Culture from a skin lesion on June 2012 confirmed Mycobacterium chelonae, which was susceptible to clarithromycin (CAM). We started treatment with CAM, imipenem/cilastatin (IPM/CS) and tobramycin (TOB) for 2 weeks. Then CAM monotherapy was continued, however CAM was discontinued because of liver dysfunction. In September 2012 new nodular lesions were observed on the left arm and right leg. We administrated azithromycin, IPM/CS and TOB. Subcutaneous nodules were partially improved, but new lesions appeared on her right leg. A culture of skin lesion yielded M. chelonae, which was highly resistant to CAM and IPM/CS. Based on the sensitivity test, moxifloxacin was used. However, there was no significant improvement in her skin lesions, so we started thermal therapy on day 57 after admission. She showed an excellent response to thermal therapy,and there has been no recurrence.

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A 51-year-old man was admitted to our hospital because of fever and diarrhea. Chest X-ray revealed consolidation in the left lower lung field. Ceftriaxone and minocycline were given empirically, under the suspicion of bacterial or atypical pneumonia. In spite of treatment with antibiotics, the disease rapidly progressed to systemic inflammatory response syndrome. The diagnosis of acute respiratory distress syndrome (ARDS) accompanied with influenza (H1N1) 2009 was made because of positive findings of real-time polymerase chain reaction. While multidisciplinary treatment was performed, his condition was further deteriorated suggesting the excessive pro-inflammatory mediators. To remove them, we conducted polymyxin-B immobilized column-direct hemoperfusion (PMX-DHP), and his general condition recovered successfully. PMX-DHP may be a useful treatment choice for ARDS accompanied with influenza.

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