A water-borne outbreak of Yersinia enterocolitica O : 8 associated with a small-scale water system occurred during July-August 2011 in Toyama Prefecture, Japan. Escherichia coli was not detected in tap water from the small-scale water system. However, the maximum concentration of viable bacteria in the tap water was 700 CFU/mL, which exceeds the legal standard for purity of tap water （100CFU/mL）．Furthermore,Y. enterocolitica O8 was isolated from the tap water with the use of immunomagnetic beads prepared with anti-Y. enterocolitica O8 antibodies. Pulsed-field gel electrophoresis analysis identified 3 isolates from tap water and 5 isolates from 4 patient stool specimens as belonging to the outbreak strain. An epidemiological investigation revealed improper management of the residual chlorine concentration in the tap water. This is the first report of an outbreak of Y. enterocolitica due to tap water from a small-scale water system in Japan.

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Artemisinin-based combination therapy (ACT) has been the standard treatment for uncomplicated malaria. Although not licensed in Japan, artemether/lumefantrine (AL), one type of ACT, has been administered to patients with malaria since 2002 by the Research Group on Chemotherapy of Tropical Diseases. Herein, we reviewed malaria cases treated with AL in Japanese travelers. A retrospective study was conducted at the National Center for Global Health and Medicine from October 2005 to March 2013. There were 19 malaria patients treated with AL, and 10 falciparum malaria patients treated with AL only. In these 10 patients treated with AL only, the median time of fever clearance was 25.0 hours (range : 14-66 hours), and the median time of parasite clearance was 36.0 hours (range : 16-62 hours). There was a positive correlation between parasitemia and time from the start of therapy to the disappearance of the parasites. Parasitemia was higher (4.05％vs. 0.24％；p＝0.044) and parasite clearance time was longer (55.5 hours vs. 31.5 hours ; p＝0.044) in the cases of recrudescence than non-recrudescence, respectively. Three of the 19 malaria patients showed recrudescence of malaria after treatment with AL. The reason that treatment failure was more frequently observed in this study than in previous reports may be related to poor absorption of lumefantrine owing to gastrointestinal symptoms, insufficiently ingested fatty foods, or high parasitemia on admission. The World Health Organization recommends that intravenous antimalarials should be administered in cases of severe malaria ; however, this is not applicable in Japan. Further studies are needed to distinguish patients with malaria who are treatable with ACT from those who should be treated initially with other intravenous antimalarials.

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To know the characteristics of methicillin-resistant Staphylococcus aureus (MRSA) strains disseminating through the Japanese community, we have determined types of Staphylococcal cassette chromosome mec (SCCmec) elements, Multi-Locus Sequence Typing (MLST), and carriages of four exotoxin genes (toxic-shock syndrome toxin, Panton-Valentine Leukocidine, and exfoliative toxins a and b) using 54 MRSA strains isolated from outpatients attending dermatology clinics at the four university hospitals of Juntendo University. Ten clonal complexes and 12 SCCmec types have been identified. As a result, more than 15 MRSA clones that were defined by the combination of genotype and SCCmec type, were identified. Among them, Clonal Complex (CC) 5-type IIa SCCmec strains were the most major (16 strains). In contrast to the fact that CC5- type IIa SCCmec strains known as a hospital-associated MRSA clone in Japan carried toxic-shock syndrome toxin gene (tst), only 2 of 16 strains have been shown to carry tst. Thirty-eight (70.4％) of isolates belonged to the clones distinct from the CC5-type IIa SCCmec strains. Among them, CC8 strains were major (12 strains),which contained 9 tst-positive CC8-type IVl SCCmec clones and a CC8-type IVa SCCmec strain carrying the Panton Valentine Leukocidin gene (lukS, F-PV). Clones related to impetigo were also identified : 7 exfoliative toxinb(etb) -positive clones, CC89-type IIa SCCmec and CC89-type V SCCmec strains ; and 2 exfoliative toxin a(eta) -positive CC121-type V SCCmec strains. Other clones were as follows : CC1-type IVa SCCmec, CC8-type ISCCmec, CC81-type IVg SCCmec, CC97-type IVc SCCmec, CC91-type IVa SCCmec, CC59-type IVg SCCmec,CC45-type IIn SCCmec, CC89-SCCmec nontypeable, and CC8-type IVm, novel subtype of type IV SCCmec were identified in this study. Our data showed that many novel MRSA clones have emerged in the community.

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We report herein on a rare case of deep-soft tissue infection due to invasive pneumococcal disease (IPD). A 77-year-old woman was admitted to our hospital with progressive pain in the right upper arm and the distal leg associated with swelling. We diagnosed the condition as multiple instances of cellulitis that were initially treated with ceftriaxone and clindamycin. Penicillin-susceptible Streptococcus pneumoniae (PSSP) was isolated from blood cultures on admission. Although inflammatory marker levels improved following susceptive antibiotic therapy (ampicillin), multiple abscesses, septic arthritis and osteomyelitis were detected with image testing. The antibiotic was then changed to meropenem and arthroscopic surgery was performed for the right shoulder ; the patientʼs clinical symptoms improved. Since pneumococcal infection including skin and soft tissue infection (SSTI) often causes blood stream invasion or metastatic suppurative complications, metastatic lesions or multiple abscesses should be taken care of.

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A 75-year-old woman with aplastic anemia was admitted to our university hospital because of a dry cough that had persisted for a month. Chest computed tomography showed a mass shadow with a central low attenuation area in the lower lobe of the left lung. Filamentous fungus resembling Aspergillus fumigatus was cultured from the specimens obtained by transthoracic needle aspiration biopsy and bronchoalveolar lavage. The initial diagnosis was a lung abscess due to A. fumigatus, although the patient did not respond well to antifungal agents. Subsequently, the filamentous fungus was identified as Aspergillus viridinutans by sequence analysis of the β-tubulin gene, and the patient was successfully treated with combination therapy along with granulocyte colony-stimulating factor. The incidence of A. viridinutans infection is very rare. A. viridinutans is morphologically similar to A. fumigatus ; however,the response to antifungal agents is generally worse than that observed in A. fumigatus infections. Therefore, the selection of agents and supplemental therapy is of vital importance in cases of A. viridinutans infection.

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Emphysematous urinary tract infection is a rare, fulminant complication that ischaracterized by the presence of gas in the pelvicaliceal system, renal parenchyma, perinephrictissues and retroperitoneum. Surgical resection is usually regarded as the treatment of choice, however several studies have shown the safety and efficacy of conservative management under the correct diagnosis and appropriate antibioticadministration. We herein report on two cases of emphysematous urinary tract infection, pyelonephritisand cystitis infected with ESBL-producing Escherichia coli,complicated with diabeticmellitus which were successfully treated with conservative treatment.

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We report two cases of Paragonimus westermani infection in a Chinese family in Japan. A 41-year-old husband and his 40-year-old wife were infected with P.westermani after consuming a homemade Chinese traditional “Drunken Crab.”They wereafamily with two children who had lived in Japan for 19 years. The crabs were Eriocheir japonica sent from the Kyusyu area that they had pickled at home with soy sauce and Chinese liquor for 5 days. Their children did not eat any of the crabs. One month after consuming the crabs,the husband came to our outpatient clinic with fever and chest painandhiswife also presented with a persistent cough. Both patients had a high peripheral blood eosinophil count (husband : 18,900/μL, wife : 10,600/μL) with pulmonary effusion, nodular shadow, and pneumothorax in chest X-ray findings. Paragonimiasis was suspected from the episode of consuming the crabs. No parasite eggs were seen in their sputum and stool samples. A multiple-dot ELISA was performed with the sera to screen for parasitic infections, but the result was only weakly positive for P.westermani antigen in the husband and a slightly positive reaction inthe wife. The diagnosisofP.westermani was achieved with the double diffusion Ouchterlony method using P. westermani antigen and P. miyazakii antigen. Praziquantel administration for three days improved the symptoms inbothpatients. The Ouchterlony method proved useful in diagnosing paragonimiasis in these cases.

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