Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of commonly used clinical antimicrobial drugs were examined for 76 strains of Streptococcus pneumoniae isolated between 2006 and 2011 from pediatric patients with invasive pneumococcal infection. Patients from whom bacterial strains were isolated ranged from 4 months to 6 years old and included 50 infants (65.8％) 1 year old and 10 (13.2％) less than 1 year old, i.e., 79.1％ of all patients studied. In diagnosis, 38 (50.0％) had occult bacteremia, 34 (44.7％) pneumonia, 3 (3.9％) meningitis, and 1 (1.3％) sepsis. Infections in all but one case who died of sepsis were treated without sequelae. The most frequent capsular serotype among isolates was 6B (20 strains,26.3％), followed by 19 F (13 strains, 17.1％) and 14 (9 strains, 11.8％). Serotypes for 55 strains (72.4％) corresponded to those contained in heptavalent pneumococcal conjugate vaccine. In classification by resistance based on mutations in penicillin-binding protein genes, 32 were penicillin-resistant S. pneumoniae (42.1％), 35 penicillin intermediate-resistant S. pneumoniae (46.1％), and 11 penicillin-susceptible S. pneumoniae (11.8％). MIC₉₀/MBC₉₀ of drugs were as follows : ampicillin 4/4μg/mL, cefotaxime 0.5/0.5μg/mL, ceftriaxone 1/2μg/mL, panipenem 0.125/0.125μg/mL, meropenem 0.5/0.5μg/mL, and doripenem 0.25/0.25μg/mL.

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Objectives: To investigate clinical and microbiological characteristics of community-acquired bacteremia (CAB). Methods: We retrospectively analyzed subjects with CAB hospitalized at Saga University Hospital between January 2009 and September 2011. We investigated causative organisms, primary infection sites, and subject summaries and complications, and analyzed the mortality factor. Results: CAB incidence was 185 cases, with 192 organisms cultured. Causative organisms were gram-positive bacteria in 81 strains (42％), 9 (11％) of which were methicillin-resistant Staphylococcus aureus (MRSA). Gram-negative bacteria were identified in 111 strains (58％), with 80％ Enterobacteriaceae. Five of the 111 (5％) were caused by extended-spectrum β-lactamase (ESBL) producing bacteria. The most frequent bacteremia portal was intra-abdominal infection (29％, 54/185). During hospitalization of 1-180 days, 20 subjects eventually died. Neutropenia on admission was associated with significantly higher mortality than without (30％vs 3％, p＜0.001). Septic shock rates were higher in non-survivors than survivors (45％vs 14％, p＝0.002), and more complications were documented in non-survivors than survivors (50％vs 25％, p＝0.017). No specific pathogen or primary infection site was associated with higher mortality. Conclusions: Antimicrobial-resistant pathogens such as MRSA and ESBL producers should be considered even in CAB, especially in subjects with healthcare-associated infection, regardless of how small the number. The CAB treatment course should consider subjects summaries, severity, and complications.

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Background : The improved survival of subjects with human immunodeficiency virus (HIV) has been accompanied by an increased prevalence of chronic kidney disease（CKD). Epidemic of CKD among those with HIV has not yet been evaluated in multiple tertiary hospitals in Japan. Methods: A cross-sectional study was conducted in 2011 at Tokyo Metropolitan Komagome Hospital (TMKH) and Tokyo Medical University Hospital (TMUH). A total of 1482 HIV-infected subjects (1384 men, 98 female, mean age : 44.2 ± 11.4 years old) were consecutively enrolled in the study. Random urine and blood samples were collected to study prevalence of CKD. CKD was diagnosed as a decrease in glomerular function and/or proteinuria and classified into 5 stages based on National Kidney Foundation guidelines. The estimated glomerular filtration rate based on serum creatinine was calculated using the 3-variable equation, constructed by the Japanese Society of Nephrology. Proteinuria was defined as ≧1＋on urine dipstick examination. All electronic medical charts were reviewed to determine comorbidities, including hypertension and diabetes mellitus (DM). The proportion of subjects receiving tenofovir disoproxil fumarate (TDF) was investigated. Risk factors for CKD were determined using multivariate logistic regression analysis. Results : The mean CD4 cell count was 487 ± 216/μL and 80.5％ had undetectable HIV-RNA level in the combined cohort. Of the 90.2％ of subjects taking antiretroviral agents, 61.5％ was using TDF. The prevalence of overall CKD and CKD ≧stage 3 was 12.9％ and 6.7％, respectively, both of which were nearly 3-fold higher in the TMKH cohort (p＜.0001). Mean age and proportional prevalent hypertension and DM were significantly higher in the TKMH cohort than in the TMUH cohort. Multivariate analysis showed significant CKD to be associated with age ≧50 years (odds ratio [OR], 2.81), hypertension (OR, 3.04), and DM (OR, 2.05). Conclusions : CKD prevalence was 12.9％ among combined cohorts, but differed significantly between them. Differences in age distribution and the proportion of comorbidities, including hypertension and DM, are likely involved.

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Primaquine phosphate has been used to prevent relapse as a radical cure after the acute-phase treatment of vivax and ovale malaria however. Many vivax malaria relapses have been reported following a standard dose of primaquine (15mg/day for 14 days). A higher dose of primaquine（30mg/day for 14 days) decreases the relapse rate, and the concomitant risk of gastrointestinal side effects tends to disappear when the drug is administered with food. G6PD deficiency is rare in the Japanese population. Although the relapsed phenomenon is reported globally, the higher dose of primaquine is currently recommended in Japan only for those returning from Southeast Asia or Papua New Guinea. Cases of 18 Japanese, including 13 vivax malaria and 5 ovale malaria, prescribed primaquine at a referral center in Japan, were analyzed retrospectively from 2007-2011. Data on diagnosis, treatment, and outcome were extracted from medical records. Of the 18, 10 with vivax malaria were administered the higher dose of primaquine. We found that only one suffered relapse-a vivax malarial case returning from Brazil and treated with the standard dose of primaquine. No ovale malarial case suffered relapse. None, including the 10 prescribed the higher primaquine dose, experienced any adverse side effects. Based on our findings, we recommend a higher dose of primaquine be used to prevent relapse when treating Japanese suffering from vivax malaria.

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We evaluated the usefulness of ImmunoCatch-Noro (Eiken Chemical Co., Ltd.) (IC-A), a newly developed immunochromatography kit using Au colloid, for the detection of norovirus in stool specimens collected from patients with acute gastroenteritis during the three-year period from 2008-2011. When a total of 316 specimens were tested by RT-PCR and direct sequencing of the PCR products, norovirus was detected in 198 specimens (62.7％), including nine genotypes (GI/2, GI/4, GI/8, GII/1, GII/2, GII/3, GII/4, GII/6 and GII/13). The most frequently isolated genotypes were GII/3 (64), GII/2 (59) and GII/4 (58), accounting for about 90％of the positive specimens. As compared to RT-PCR, the sensitivity, specificity and concordance rate of IC-A were 87.4％(173/198), 100％(118/118) and 92.1％(291/316), respectively. Twenty-five positive specimens that were positive by RT-PCR were negative by IC-A, however there were no false-positive results of IC-A. On the other hand, the commercially available immunochromatography kit (IC-B), which was tested for comparison, had a sensitivity, specificity and concordance rate of 59.6％(118/198), 96.6％(114/118) and 73.4％(232/316), respectively, containing 80 false-negative and four false-positive specimens. All of the 118 specimens positive by both IC-B and RT-PCR were also interpreted as positive by IC-A. The detection rates of the predominant genotypes (GII/2, GII/3 and GII/4) by IC-A were 88.1％, 87.5％ and 89.7％, respectively. In contrast, those by IC-B were only 32.2％, 67.2％and 81.0％, respectively. These results show that IC-A had adequate sensitivity and cross-reactivity for a wide range of GI and GII genotypes, and also had high specificity. In conclusion, IC-A is a useful rapid-diagnostic kit for the detection of norovirus, however, its current application is limited for stool specimens.

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Clostridium tetani is widely distributed in ground or mud, especially in field and pond-shore surface layers. C.tetani is rarely isolated from specimens of patients with tetanus, and is generally diagnosed based on clinical symptoms such as trismus or general tonic spasms. This means that positive C. tetani infection is rarely diagnosed bacterially. Using gram straing, we identified C. tetani in specimens from patients suspected of C. tetani infection brought to the Kitasato University Hospital emergency center. Rapid gram staining information in the bacteriology laboratory is expected to improve recovery from C. tetani infection. It is therefore necessary to ensure clinical specimen quality control, and to keep standard strains of rare bacteria for isolation and identification.

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We report a case of severe Cushingʼs syndrome developing into life-threatening acute respiratory distress syndrome with cryptococcus and cytomegalovirus co-infection soon after hypercortisolism treatment using metyrapone, an 11-β-hydroxylase inhibitor. We speculate that a restored immune response would have elicited clinical symptoms of opportunistic and previously subclinical infection. The immunocompromised state and the delicate glucocorticoid balance in subjects with severe Cushingʼs syndrome necessitate a specific diagnostic and therapeutic approach.

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A 42-year-old woman presenting with years of fever and vague symptoms could not be satisfactorily diagnosed in physical examination or conventional workups. She was presumptively diagnosed with chronic fatigue syndrome and treated symptomatically. Fourteen months after the initial visit, she developed left facial palsy. Lyme disease serology was positive. Four weeks of oral amoxicillin ameliorated symptoms. Only 5 to 15 cases of Lyme disease are reported annually in Japan, mostly from the northeastern-most island of Hokkaido. It may occur anywhere in Japan, however; probably is underdiagnosed. Lyme disease may cause fevers of unknown origin. Astute clinical suspicion and appropriate workups are thus needed to diagnose this infection.

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A 58-year-old male developed epigastric discomfort and high fever in 2010. Complete blood count showed leukocytosis and a small number of atypical lymphocytes. Gastric endoscopy revealed multiple gastroduodenal erosions and ulcers. Biopsy specimens were obtained and pathological examination demonstrated cytomegalic inclusion bodies. Cytomegalovirus (CMV) IgM antibody was positive and CMV DNA was detected with PCR in his blood, leading to the diagnosis of CMV gastroduodenitis. He was treated with intravenous ganciclovir and his symptoms resolved rapidly. It is recognized that CMV gastroduodenitis is extremely rare in immunocompetent hosts but sometimes shows a severe clinical course in elderly patients. The results from our present patient suggest that we should consider CMV infection in the differential diagnosis of multiple gastroduodenal erosions and ulcers. Our data also suggested that anti-CMV medications could be important treatment options for CMV gastroduodenitis, especially in elderly patients.

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