(1-＞3)-β-D-glucan (BDG) is a constituent of the fungal cell wall and its blood level is known as a marker of fungal infection including pneumocystis pneumonia (PCP). Meanwhile, peripheral blood neutrophil CD64 expression (CD64) is upregulated in various infections. We analyzed patients with positive BDG (cut off 11.0 pg/mL) and those whose CD64 was measured simultaneously. In patients who visited our hospital from 2005 to 2011, BDG was measured in 3,960 samples. The number of positive samples were 441 obtained from 185 patients. In patients with positive BDG, the initial BDG was 24.3 [16.4―70.5] pg/mL (median [interquartile range]). Positive BDG samples were derived mainly from the department of Rheumatology or that of Allergy and Respirology. Common primary diseases were rheumatoid arthritis (RA) or other connective tissue diseases, followed by malignancy, none (only abnormal chest X-ray) and bronchial asthma. The rates of afebrile patients, patients on immunosuppressive therapy and those with a normal range of white blood cell count were 63.7%, 50.9% and 40.8%, respectively. The main causes of positive BDG were PCP (n＝38, 20.5%) and non-PCP mycosis (n＝48, 25.9%, including 26 cases of aspergillosis). Others (99 patients, 53.6%) had positive BDG of unknown origin and 53 of them ameliorated spontaneously, most of whom could have been examples of pseudo-positive BDG. The number of deceased patients was 57 (30.8%) consisting of 9 PCP, 16 non-PCP mycosis and others. The median initial positive BDG levels in patients with PCP, non-PCP mycosis and others were 49.9, 28.9 and 19.7pg/mL, respectively. The positive rate of CD64 (cut off 2,000 molecules/cell) measured simultaneously with initial positive BDG was 77.8%. In RA patients with PCP, 94.7% of them had positive CD64 and the levels of CD64 were significantly higher than those in RA patients with bacterial pneumonia (median 9,386 vs 4,399 molecules/cell) in that same period. The positive rate of CD64 was lower in patients with positive BDG of unknown origin than those with PCP or non-PCP mycosis, which implies positive CD64 can exclude pseudo-positive BDG. Immunosuppressed patients often exhibit positive BDG. Simultaneous measurement of BDG and CD64,a quick pan-infection marker, assists the decision whether the positive BDG is true or false-positive.

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Currently in Japan, the only approved influenza vaccine is the inactivated vaccine which is injected subcutaneously. On the other hand, there is a live vaccine available elsewhere in the world. Flumist, an intranasal influenza live vaccine which contains four strains of infectious viruses, has been used in the United States for more than 10 years；the vaccine has been found effective in clinical trials, while it has some limitations such as those on subjects for the administration, strict storage conditions, relatively short expiration date etc. It is not yet approved in Japan, but available through personal import by some medical institutions,and prescribed based on the decision of the doctor. However, in Japan, there is no checking system whether the vaccine contains appropriate amounts of infectious viruses or not. In the present study, we purchased 2013―14 and 2014―15 yearsʼlots of Flumist from a parallel importer and measured the amount of infectious viruses of each component of them using the focus assay. Consequently, for type A influenza viruses, the titers of both of H1N1pdm09 and H3N2 viruses in the 2013―14ʼs lot were 1/30 of the lower limit of those shown in the package insert and 1/10 in 2014―15ʼs lot, while those of type B viruses, both of B/Massachusetts and B/Brisbane viruses marginally cleared the lower limit. The digital PCR analysis showed that the absolute genome copy numbers of type A viruses were 1/10 of those of type B viruses. The relatively higher titer of B/Massachusetts also gradually decreased over time during its storage at 4̊C and finally reached the lower limit at about one week before the expiration date. In case it is approved officially in the future to be used in Japan, some studies will be required to elucidate the minimum viral titers of the components necessary for effective live vaccine. In addition, there should be a system to check the titer during the distribution process in Japan.

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Little is known about the clinical characteristics of invasive infections caused by nontyphoidal Salmonella sp. in childhood and the temporal changes of their incidence over a long period of time. In order to clarify these issues, we retrospectively analyzed the records of 17 such infected children admitted between August 1994 and December 2014 to our center. We divided the study period into the first (1994―1999), second (2000― 2004), third (2005―2009), and fourth (2010―2014) periods. The ages of the 17 patients ranged from 2 days to 13 years. Clinical syndrome included bacteremia with enteritis (n＝13), followed by bacteremia or sepsis alone (n＝2), osteomyelitis (n＝1), and meningitis (n＝1). The affected patient numbers in the first to fourth periods were 10, 5, 2, and 0, respectively, and the decreasing trend was significant (trend p＜0.001). This significant trend held up even after correction by the number of in-patients during each quarter period (trend p＝0.009). In the 14 cases of bacteremia with or without enteritis, excluding two neonatal cases and one case of osteomyelitis, most patients (n＝13, 93％) had WBC of ＜15,000/μL with a wide range of serum CRP levels (0.8―20.4mg/dL) on admission. Thus, it was very difficult to diagnose these bacteremia cases based on blood tests alone, and we needed to consider such risk factors of bacteremia as high fever, poor general condition,and younger age. O group serotypes of the isolates were as follows： O9 (n＝11), O7 (n＝5), and O4 (n＝1). Of the 15 strains evaluated, two strains were resistant to ampicillin and one each was resistant and intermediately resistant to fosfomycin. All strains were susceptible to cefotaxime, ofloxacin or levofloxacin, and trimethoprim-sulfamethoxazole. We were also presented with two rare cases：one involved sepsis due to vertical transmission and the other involved meningitis. The latter case had clinical relevance in that recurrence developed 3 weeks after treatment with susceptible antibiotics. In conclusion, this study is the first report on invasive infections caused by nontyphoidal Salmonella sp. in childhood in Japan, and provides important information on their clinical features and incidence trends over the last 20 years.

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Extremely early diagnosis of human immunodeficiency virus (HIV) infection has been considered highly important for its treatment. We conducted a performance assessment of a newly developed rapid diagnostic reagent for HIV by using a fourth-generation immunochromatographic assay (Alere HIV Combo). We used whole-blood, plasma, and serum samples obtained from 250 Japanese adults who visited the Kawasaki Medical School Hospital and underwent HIV screening tests. We also used 12 types of commercial HIV-1 seroconversion panels and World Health Organization standard antigens. This method, which has a detection sensitivity of 100% and a specificity of 99.3%, was as accurate as the chemiluminescent immunoassay (CLIA) method. In a sensitivity test using seroconversion panels in the early phase of infection, the mean duration until positive conversion was 19.3 days. With this method having a high detection sensitivity for HIV-1p24 antigen, the results from whole-blood samples were the same as those from plasma and serum samples. Therefore, it can be considered as a useful rapid measurement method for general practice.

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Streptococcus suis is a major swine pathogen. It has recently been recognized as an emerging zoonosis that causes mainly meningitis and sepsis in human. In particular, toxic shock-like syndrome (TSLS) caused by this pathogen has a high mortality rate. However, misidentification of S. suis by conventional biochemical and commercial identification tests is not rare. The patient was a 71-year-old man who worked as a pig farmer who was admitted for fever, oliguria and subcutaneous hemorrhage. He was diagnosed as having septic shock and blood culture was positive for Gram-positive cocci, mainly diplococcus. This pathogen was identified with S. suis with using MALDI-TOF MS analysis, though a commercial Gram-Positive bacteria identification kit revealed viridans streptococci. His clinical features met the diagnostic criteria of TSLS, and ceftriaxone and clindamycin were administered. On admission day 28, he was discharged in good condition.

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