Search

Pre-exposure prophylaxis (PrEP) with tenofovir/emtricitabine (TDF/FTC) has been recommended worldwide. We evaluated the safety and efficacy of daily PrEP with TDF/FTC in Tokyo. This single-center, single-arm study was performed with 124 men who have sex with men (MSM) between January 2017 and March 2021. MSM who entered into an MSM cohort from January 2017 through March 2018 and had a pre-PrEP observational period of 1 year were eligible and recruited to the study between April 2018 and March 2019 and followed for 2 years. The primary outcome was the incidence of HIV infection (per 100 person-years). Secondary outcomes were the incidence of sexually transmitted infections and adverse events, and the rate of retention and adherence to PrEP. There were 309 MSM registered in the cohort (mean age, 36.6 years); 124 fulfilled the criteria and were included in the study. The remaining patients were continuously followed. There was a significant decrease in incidental HIV infection among PrEP users (0 infections, 235.5 person-years) compared to non-PrEP users (11 infections [3.4%/year], 318.9 person-years; p = 0.01). The average adherence rate was consistently greater than 95%, and the retention rate at two years was approximately 80%. The present study showed a high prophylactic effect against HIV infection, retention, and adherence to PrEP. PrEP is feasible and highly recommended in Japan. UMIN Clinical Trials Registry (UMIN000031040, www.umin.ac.jp), Japan Registry of Clinical Trials (jRCTs031180134). [ABSTRACT FROM AUTHOR]

Background: Amebiasis, caused by Entamoeba histolytica, is spreading in developing countries and in many developed countries as a sexually transmitted infection. Here, we evaluated the efficacy of serological screening to identify asymptomatic E. histolytica infection as a potential epidemiological control measure to limit its spread. Methodology/Principal findings: This cross-sectional study was carried out between January and March 2021 in an HIV-negative men who have sex with men (MSM) cohort at the National Center for Global Health and Medicine. Serological screening was performed using a commercially available ELISA kit. For seropositive individuals, we performed stool polymerase chain reaction (PCR) to determine current E. histolytica infection. We performed E. histolytica serological screening of 312 participants. None had a history of E. histolytica infection prior to the study. The overall E. histolytica seropositivity was 6.7% (21/312), which was similar to that found by the rapid plasma reagin test (17/312). We identified current infection in 8 of 20 seropositive participants (40.0%) by stool PCR. Conclusions/Significance: Our serological screening approach constitutes a potentially practical epidemiological strategy. Active epidemiological surveys, in combination with an effective screening strategy for asymptomatically infected individuals, should be applied to help reduce sexually transmitted E. histolytica infections. Author summary: Amebiasis, caused by Entamoeba histolytica, is now spreading not only in developing countries, but also in many of developed countries. Unlike the situation in developing countries, transmission occurs directly from one infected person to another via sexual contact, called sexually transmitted E. histolytica infection. Furthermore, most cases of E. histolytica infection are asymptomatic, who can be a reservoir for sexual transmission in the community. Cost-effective epidemiological strategy is urgently needed. Hereby, we performed a serological test for 312 "asymptomatic" HIV-negative men who have sex with men to assess the effective screening method for E. histolytica infection. We identified 21 seropositive samples (6.7% of seropositivity, 21/312), in which relatively high seropositivity to E. histolytica was seen among the participants with positive serology for Treponema pallidum hemagglutination (TPHA) or hepatitis B core antibody (HBcAb). Finally, we identified current infection (asymptomatic E. histolytica infection) in 8 out of 20 stool sampling cases (40.0%) by polymerase chain reaction. Our serological screening assay provides a potentially practical epidemiological strategy. Active epidemiological survey, in combination with the effective screening strategy for asymptomatically infected individuals are considered for the future control of sexually transmitted E. histolytica infection. [ABSTRACT FROM AUTHOR]

Men who have sex with men (MSM) have been disproportionally affected by the HIV epidemic in many countries, including Japan. Although pre-exposure prophylaxis (PrEP) is a strong prevention tool, it is not yet approved in Japan. A Markov model was developed to describe HIV infection and disease progression in an MSM cohort (N = 1000) in Japan receiving a PrEP program. The model was used to evaluate the cost-effectiveness of a PrEP program. HIV/AIDS treatment, screening, hospitalization due to AIDS, and PrEP were considered as costs and quality-adjusted life-years (QALYs) gained as utilities. Cost-effectiveness was assessed by comparing the incremental cost-effectiveness ratio (ICER) over a 30-year period against the willingness to pay (WTP) threshold. One-way sensitivity and probabilistic sensitivity analyses were performed. With 50% PrEP coverage, the PrEP program became dominant against the program without PrEP, using a threshold of 5.0 million JPY/QALY (45,455 USD). The probabilistic sensitivity analysis revealed that the PrEP program was dominant or at least cost-effective in most cases of 10,000 simulations. Therefore, preparing cheaper PrEP pills, which results in PrEP being dominant or ICER being lower than the WTP threshold, is important to make the program cost-effective. Introduction of PrEP to an MSM cohort in Japan would be cost-effective over a 30-year time horizon. [ABSTRACT FROM AUTHOR]

Background Evidence on efficacy of high-dose ceftriaxone monotherapy for extragenital Neisseria gonorrhoeae (NG) infection is lacking. Methods A cohort of men who have sex with men (MSM) were tested for NG/ Chlamydia trachomatis (CT) every 3 months, in a single-center observational study in Tokyo, Japan. MSM aged > 19 years diagnosed with extragenital NG infection between 2017 and 2020 were included. A single dose of 1 g ceftriaxone monotherapy was provided, while dual therapy with a single oral dose of 1 g azithromycin or 100 mg doxycycline administered orally twice daily for 7 days were given, for those coinfected with CT, according to infected sites. Efficacy of these treatments was calculated by the number of NG-negative subjects at test-of-cure divided by the number of subjects treated. Fisher exact tests were used to compare the efficacy between the 2 groups. Results Of 320 cases diagnosed with extragenital NG, 208 were treated with monotherapy and 112 were treated with dual therapy. The efficacy against total, pharyngeal, and rectal infections was 98.1% (204/208, 95% confidence interval [CI]: 95.2–99.3%), 97.8% (135/138, 95% CI: 93.8–99.4%), and 98.6% (69/70, 95% CI: 92.3–99.9%), respectively, in the monotherapy group, whereas the corresponding efficacy in the dual therapy was 95.5% (107/112, 95% CI: 90.0–98.1%), 96.1% (49/51, 95% CI: 86.8–99.3%), and 95.1% (58/61, 95% CI: 86.5–98.7%), respectively. No significant difference in the corresponding efficacy was observed between the two groups (P  = .29, P  = .61, P  = .34, respectively). Conclusions High-dose ceftriaxone monotherapy is as effective as dual therapy for extragenital NG among MSM. [ABSTRACT FROM AUTHOR]

Anal high-risk human papillomavirus (hr-HPV) infection is widely considered a cause of anal cancer. However, epidemiological data are quite limited in Japan. This study investigated anal HPV infections and cytological abnormalities among MSM with or without HIV infection. Anal swabs were obtained, and cytological results were examined. Hybrid capture-based methodology was used for hr-HPV genotyping. The exclusion criterion was a history of vaccination against HPV. 644 subjects participated, and the overall prevalence of hr-HPV was 59.7% (95% CI 54.7–62.3), HIV-infected had higher prevalence than HIV-uninfected (68.9% vs 40.6%) p <.001. Among hr-HPV-infected participants, 82.8% (312/377) were infected with at least one of 9 valent vaccine-covered hr-HPV genotypes. From regression analysis, detection of abnormal cytology correlated positively with HIV infection (OR 2.17 [95% CI 1.51–3.13]), number of hr-HPV genotypes infected (OR 1.83 [1.59–2.10]), history of STI (OR 1.58 [1.14–2.22]) and No. of lifetime sexual partners (OR 1.56 [1.10–2.21]), albeit multivariate analysis identified the number of detected hr-HPV genotypes (adjusted OR 1.78 [1.54–2.06]) as the independent risk factor for abnormal cytology. High rates of anal hr-HPV infection, especially 9-valent HPV vaccine-preventable hr-HPV were detected among our MSM participants in Japan. HPV vaccination should also be encouraged for MSM in Japan. [ABSTRACT FROM AUTHOR]

This single-institution cross-sectional study aimed to grasp the prevalence and features of neurocognitive dysfunction in HIV-infected hemophilia patients in Japan. We conducted neuropsychological tests and medical examinations in 56 HIV-infected hemophilia patients who received outpatient treatment at the AIDS Clinical Center, National Center for Global Health and Medicine. A total of 388 HIV-infected non-hemophilia patients who received outpatient treatment at the same institution were included as a control group. To investigate sites responsible for neurocognitive dysfunction in HIV-infected hemophilia patients using brain FDG-PET/CT scans, the accumulation of FDG in each brain region was compared. Approximately 50% of HIV-infected hemophilia patients had neurocognitive dysfunction. The prevalence of asymptomatic neurocognitive impairment was high (34%). Neurocognitive dysfunction was associated with educational level in HIV-infected hemophilia patients. In the symptomatic group, hemophilic arthropathy and history of cerebrovascular disorders were associated with neurocognitive dysfunction. Left temporal lobe function was reduced in the symptomatic group. [ABSTRACT FROM AUTHOR]

Background: Rectal Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections have been neglected and epidemiological data are unavailable in Japan. Thus, we evaluated the prevalence and incidence of rectal CT/NG in a cohort of HIV-negative men who have sex with men (MSM), which was established at the National Center for Global Health and Medicine (NCGM), in Tokyo, Japan, in January 2017. Methods: HIV-negative MSM aged ≥16 years old were included. The prevalence of rectal CT/NG among HIV-negative MSM was compared with that among an existing HIV-positive MSM cohort at NCGM. The HIV-negative MSM cohort was examined for rectal and pharyngeal CT/NG every 3 months. Urethral CT/NG was evaluated at the physician's discretion. The incidences of CT/NG were evaluated in December 2018. Results: Of 502 MSM initially included in this study, 13 men were diagnosed with HIV infection at enrollment and were subsequently excluded from the analysis. We evaluated 561 HIV-positive MSM for rectal CT/NG. The mean ages of the two cohorts were 33.6 and 46.2 years old, respectively (p<0.001). The prevalences of rectal CT were 16.4% and 15.9% (p = 0.707) and the prevalences of rectal NG were 4.1% and 2.3% (p = 0.101), for the HIV-negative and HIV-positive MSM cohorts, respectively. Of 489 HIV-negative MSM, 328 were followed at least twice, with 261.1 person-years during the study period. The incidences of rectal CT/NG were 17.2 and 3.8/100 person-years and the incidences of pharyngeal CT/NG were 2.0 and 11.0/100 person-years for the two cohorts, respectively. Approximately 37.9% of incident cases were attributed to recurrent infection. Conclusions: The prevalence and incidence of rectal CT/NG were high among MSM in Tokyo, Japan, suggesting that urgent countermeasures for early diagnosis and treatment are necessary. [ABSTRACT FROM AUTHOR]

There is no detailed information on the association between age, time of disease, and HIV-associated neurocognitive disorders (HAND). In this prospective study involving 17 medical facilities across Japan, we recruited HIV-infected patients to complete a 14-test neuropsychological battery that assess eight neurocognitive domains. HAND were diagnosed by the Frascati criteria. Of 1399 recruited patients, 728 were enrolled. The prevalence of HAND was 25.3% [13.5% asymptomatic neurocognitive impairment, 10.6% mild neurocognitive disorder (MND), and 1.2% HIV-associated dementia (HAD)]. Tests that assess executive and visuospatial functions showed better diagnostic accuracy than other tests for HAND. Multivariate analysis identified age (≥ 50 years) and incomplete virological suppression as risk factors for MND and HAD and current ART as a protective factor. The prevalence of MND and HAD was low in the early stage of infection (6.3% in ≥ 2 to < 6 years), then increased in the later stage [17.3% in ≥ 11 years, p = 0.001 (vs. ≥ 2 to < 6 years)], independent of age or treatment. Older patients were more likely to show MND or HAD in the early stage of HIV infection (26.7 vs. 8.7% for < 2 years and 17.4 vs. 3.1% for ≥ 2 to < 6 years, p = 0.040 and 0.004, respectively) compared to younger ones. In conclusion, MND and HAD were more commonly found in later years since diagnosis of HIV infection and older patients are at risk of neurocognitive impairment at the early stage of HIV infection. Tests for executive and visuospatial functions seem more sensitive than other tests for diagnosing HAND. [ABSTRACT FROM AUTHOR]

Objective: To examine the prevalence of illicit drug use among men who have sex with men (MSM) with HIV-1 infection in Japan, where the life-time prevalence of illicit drug use in the general population is only 2.9%. Design: A single-center cross-sectional study at a large HIV clinic in Tokyo, which treats approximately 15% of HIV-1 infected patients in Japan. Methods: The prevalence of illicit drug use and the assciation of characteristics and social demographics of the patients with illicit drug use were examined. Patients who visited the clinic for the first time from 2005 to 2010 were enrolled. Relevant variables were collected using a structured interview and from the medical records. Multivariate logistic regression analyses were applied to estimate the odds of association of MSM over non-MSM HIV-infected patients with illicit drug use. Results: 1,196 patients were enrolled. They were mostly Japanese men of relatively young age. Illicit drug use (including injection drugs) was reported by 35% of the patients (by 40% of MSM), and 4% were IDU while 5% were on methamphetamine. 2% of the population was arrested due to illicit drugs. MSM was significantly associated with illicit drug use (adjusted OR = 4.60; 95% CI, 2.88–7.36; p<0.01). Subgroup analysis of the patients stratified by three age groups (≤30, 31 to 40, and >40) showed that the odds of association of MSM with illicit drug use was the strongest in the youngest age group (≤30 years: adjusted OR = 7.56; 95% CI, 2.86–20.0; p<0.01), followed by the oldest (>40 years: adjusted OR = 6.15; 95% CI, 2.40–15.8; p<0.01), and the weakest in the group aged 31 to 40 (adjusted OR = 3.39; 95% CI, 1.73–6.63; p<0.01). Conclusions: The prevalence of illicit drug use is high among MSM patients with HIV-1 infection in Japan. Effective intervention for illicit drug use in this population is warranted. [ABSTRACT FROM AUTHOR]

The association between tenofovir-induced kidney tubulopathy and polymorphisms in genes encoding transporters in Japanese patients was elucidated. Patients with genotypes −24 CC and 1249 AA of ABCC2 were almost 40 times more likely to develop tubulopathy than those without these genotypes.Background. Tenofovir is a widely used antiretroviral drug although it can cause kidney tubular dysfunction (KTD). The aim of this study was to determine the association between polymorphisms in genes encoding drug transporters and KTD in Japanese patients treated with tenofovir.Methods. The association between tenofovir-induced KTD and 14 single nucleotide polymorphisms (SNPs) in the ABCC2, ABCC4, ABCC10, SCL22A6, and ABCB1 genes was investigated in 190 Japanese patients. KTD was diagnosed by the presence of at least 3 abnormalities in the following parameters: fractional tubular resorption of phosphate, fractional excretion of uric acid, urinary β2-microglobulin, urinary α1-microglobulin, and urinary N-acetyl-β-D-glucosaminidase. Genotyping was performed by allelic discrimination using TaqMan 5′-nuclease assays with standard protocols. Associations between genotypes and KTD were tested by univariate and multivariate logistic regression analyses.Results. KTD was diagnosed in 19 of the 190 (10%) patients. Univariate and multivariate analyses showed a significant association between KTD and genotype CC at position −24 CC (adjusted odds ratio [OR], 20.08; 95% confidence interval [CI], 1.711–235.7; P = .017) and genotype AA at position 1249 (adjusted OR, 16.21; 95% CI, 1.630–161.1; P = .017) of ABCC2. Multivariate analysis showed higher adjusted OR for patients with both homozygotes (adjusted OR, 38.44; 95% CI, 2.051–720.4; P = .015). ABCC2 haplotype −24T and 1249G was a protective haplotype for KTD (OR, 0.098; 95% CI, .002–.603; P = .003Conclusions. This is the first study of our knowledge to identify the association between SNPs in ABCC2 and tenofovir-induced KTD in an Asian population. Close monitoring of renal function is warranted in tenofovir-treated patients with these SNPs. [ABSTRACT FROM AUTHOR]

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA), which often produces Panton-Valentine leukocidin (PVL), is an emerging threat in the community. In Japan, for example, PVL-positive ST8 CA-MRSA (USA 300), which originated from the United States, persisted in families for a year and caused severe invasive infection in a child. In this study, we describe a long-term familial infection cluster caused by novel PVL-positive CA-MRSA, which most probably originated from India. This MRSA persisted in related families for more than 2 years with colonization of, for example, the nares and cheek. At least 6 of 12 members (50%) developed deep cutaneous abscesses, including recurrent and multifocal abscesses, every 1.2 months on average. All MRSA isolates from colonization and abscesses were the same, albeit with a variant in pulsed-field gel electrophoresis analysis. The MRSA exhibited the genotype ST22/ spa113(t005)/SCC mecIVa/coagulase gene ( coa) novel type and strong hemolysis activity. Moreover, the MRSA exhibited high biofilm formation (which was markedly enhanced by sub-MICs of oxacillin). Some patients were treated with levofloxacin, with successful MRSA eradication even from the whole body surface sites; however, short-term patient follow-up was not sufficient to demonstrate eradication of the familial infection cluster. The data suggest that PVL-positive novel ST22 CA-MRSA emerged in Japan, causing a long-term familial infection cluster, and that the success of ST22 CA-MRSA as both a colonizer and a pathogen could result from the combination of its strong biofilm formation and other virulence factors. A long-term patient (or carrier) follow-up is needed in the community. [ABSTRACT FROM AUTHOR]

Background: Men who have sex with men (MSM) are at high risk of HIV infection. However, there are only few data on HIV prevalence in MSM in Japan. The objective of this study was to explore the HIV prevalence in MSM at Shinjuku 2-chome, a well known gay quarter in Tokyo.Methods: MSM directly collected the dried blood spot (DBS) self-collection HIV test kit from a drop-in center in Shinjuku 2-chome between August 2015 and December 2016. The participants collected their own blood by finger-prick and anonymously posted the kit to the laboratory. The participants accessed the study website and checked the results of their tests using unique ID and password. DBS was soaked in phosphate buffered saline overnight and the eluted sample was examined by the fourth generation HIV Ag/Ab test of LUMIPULSE (FUJIREBIO INC.), and followed by HISCL (Sysmex Corp.) when the first assay was positive. The result was defined provisionally positive if both were positive.Results: A total of 1702 HIV test kits were distributed and 1403 DBS were returned (return rate: 82.4%). Since 20.2% of participants collected the test kit more than once, the estimated number of actual test kit users was 1120. Based on the results of the test kit, 34 cases were provisionally diagnosed with HIV. The estimated prevalence was 3.04% (95% confidence interval: 2.03-4.04). Of these 34, 24 (70.6%) were later confirmed to be HIV-positive in the hospital, while the remaining 10 were lost to follow-up. Among the participants, 34.5% received HIV test for the first time. Especially in those aged 20-29, 46.0% were first time HIV testers.Conclusions: The prevalence of HIV infection in the study population was 3.04%. The high collection suggested a demand for this type of testing in MSM. The test should be expanded further to difficult-to-reach or hidden populations.Trial Registration: This study was registered with the University Hospital Medical Information Network Clinical Trial Registry in August 20th, 2015 (Registry number: UMIN000018699 ). [ABSTRACT FROM AUTHOR]

We prospectively assessed asymptomatic monkeypox virus infections among men who have sex with men in Tokyo, Japan, during the initial phase of the mpox epidemic. Our findings suggest that asymptomatic infections were likely underestimated and were comparable in magnitude to symptomatic infections, highlighting the need to improve testing accessibility among high-risk populations.

Objectives: To assess whether pooled sample testing with nucleic acid amplification tests was a potential alternative to three single-site sample testing to screen for Chlamydia trachomatis and Neisseria gonorrhoeae infections in asymptomatic men who have sex with men., Methods: We prospectively compared pooled sample testing with single-site sample testing in asymptomatic MSM. Self-obtained paired rectal samples, one gargle sample and one first-void urine sample were collected from participants to generate two sets of samples: one for pooled sample testing and the other for single-site testing. We used modified pooled sampling, which is defined as the use of gargle samples, instead of swabs, for the pooled sample to test for pharyngeal infection., Results: This study included 513 MSM. The positive rates of C. trachomatis and N. gonorrhoeae were 20.3% and 11.7%, respectively, for single-site sample testing. Compared with the sensitivity of single-site testing as the gold standard, the sensitivities of pooled sample testing for C. trachomatis and N. gonorrhoeae were 94.2% (95% CI 88.0% to 97.3%) and 98.3% (95% CI 90.9% to 99.9%), respectively. The concordance rate and kappa coefficient were 98.3% (95% CI 96.7% to 99.2%) and 0.945 (95% CI 0.859 to 1.000), respectively, for C. trachomatis and 98.8% (95% CI 90.1% to 100%) and 0.943 (95% CI 0.857 to 1.000), respectively, for N. gonorrhoeae ., Conclusions: The modified pooled sampling had a comparably high consistency with single-site sample testing. The results strongly suggest that the gargle sample is suitable as a part of pooled sample for STI screening of C. trachomatis and N. gonorrhoeae ., Competing Interests: Competing interests: SO has received research grants/materials from Gilead Sciences, MSD KK, CSL Behring and ViiV Healthcare, Co., and has received honorarium for lectures from MSD KK, Gilead Sciences, ViiV Healthcare and Janssen Pharmaceutical, KK., (© Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Objectives: To compare the effectiveness of doxycycline 100 mg twice daily for 7 days and azithromycin 1 g single dose for the treatment of rectal Chlamydia trachomatis infection among MSM in a real clinical setting., Methods: A prospective study was performed to compare the effectiveness of doxycycline and azithromycin for the treatment of rectal C. trachomatis among MSM in Tokyo, Japan. Subjects diagnosed with rectal C. trachomatis infection were treated and test-of-cure examination (TOC) was performed at least 3 weeks after the treatment. Treatment of rectal C. trachomatis infection was decided prospectively in a time-dependent manner; in the period between January 2017 and October 2018, azithromycin was administered to all subjects, whereas from October 2018 through March 2020, doxycycline was administered to all subjects. Effectiveness of these treatments was calculated by the number of rectal C. trachomatis-negative subjects at TOC divided by the number of subjects treated., Results: Two hundred and ninety-six MSM with rectal C. trachomatis infection were treated with azithromycin (80 patients) and doxycycline (216 patients) in a time-dependent manner. Of the 296 MSM, 274 (92.6%) were treated successfully [67 (83.7%, 95% CI = 79.6%-87.9%) in the azithromycin group versus 207 (95.8%, 95% CI = 94.5%-97.2%) in the doxycycline group, P < 0.001]. To evaluate factors associated with treatment failure, we performed logistic regression analysis. In univariate and multivariate analysis, only doxycycline treatment was inversely associated with treatment failure (OR = 0.29, 95% CI = 0.084-0.976, P = 0.046)., Conclusions: The treatment with doxycycline 100 mg twice daily for 7 days was superior to that with azithromycin 1 g single dose for rectal C. trachomatis among MSM in a real-world setting., (© The Author(s) 2020. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Background: The natural course of HIV-1 infection includes 10 years of an asymptomatic period before the development of AIDS. However, in Japan, the disease progression process seems faster in recent years., Methods: The study subjects were 108 new patients with primary HIV-1 infection during the period from 1997 through 2007. We evaluated their clinical symptoms and laboratory data, and then analyzed disease progression in 82 eligible patients. Disease progression was defined as a fall in CD4 count below 350/µL and/or initiation of antiretroviral therapy., Results: Ninety percent of the patients were infected via homosexual intercourse. All patients had at least one clinical symptom (mean; 4.75±1.99) related to primary HIV-1 infection, with a mean duration of 23.2 days (±14.8) and 53.3% of them had to be hospitalized due to severe symptoms. The mean CD4 count and viral load at first visit were 390/µL (±220.1) and 4.81 log10/mL (±0.78), respectively. None developed AIDS during the study period. Estimates of risk of disease progression were 61.0% at 48 weeks and 82.2% at 144 weeks. In patients who required antiretroviral therapy, the median CD4 count was 215/µL (range, 52-858) at initiation of such therapy. Among the patients with a CD4 count of <350/µL at first visit, 53% never showed recovery of CD4 count (>350/µL) without antiretroviral therapy., Conclusion: Despite possible bias in patient population, disease progression seemed faster in symptomatic Japanese patients with recently acquired primary HIV-1 infection than the previously defined natural course of the disease.

Background: Streptococcus pneumoniae and Haemophilus influenzae infections in children with influenza have been noted because of the severity of co-infection. In Japan, vaccination against S. pneumoniae and H. influenzae infections has been listed in the vaccine program in 2008, but the characteristics of the two organisms, colonizing at the initial stage of influenza infection, have not been investigated in detail., Methods: Nasopharyngeal swabs from children with influenza (flu(+)) (n= 236; mean age, 6.2 years) were examined for bacterial pathogens, including S. pneumoniae and H. influenzae. They were then examined for serotypes, drug susceptibilities, and resistance genes (or gene mutations). As a reference, children with upper respiratory tract infection (URTI(+), flu(-); n = 189; mean age, 6.2 years) were also examined., Results: S. pneumoniae, beta-streptococci (groups A, B, and G), methicillin-susceptible and -resistant S. aureus, Moraxella catarrhalis, and H. influenzae were isolated. For S. pneumoniae, nine serotypes were detected with prevalent types of 3, 6, 19 and 23. Penicillin resistance was detected in types 19 and 23, while resistance to macrolide and clindamycin was found in various types. For H. influenzae, only b serotype was detected, with marked ampicillin resistance. The majority was non-typeable. Very similar results were obtained even in URTI(+) (flu(-)) cases., Conclusion: Multiple drug-resistant S. pneumoniae with major serotypes, for example, 19 and 23 and H. influenzae with serotype b were already present at the initial stage of influenza infection, similar to URTI(+) flu(-) cases. They could be prevented by current vaccines, but drug-resistant non-typeable H. influenzae is troubling.

Pseudomonas aeruginosa is an opportunistic pathogen that causes disease in patients with impaired host defenses; it is often a cause of life-threatening nosocomial infection in critically ill and immunocompromised patients. An increase in the prevalence of multiple-drug-resistant Pseudomonas aeruginosa (MDRP) in hospitals is thus a worldwide problem. These increases are frequently related to the high selective pressure of antimicrobials commonly used in hospitalized patients, particularly extended-spectrum cephalosporins, beta-lactamase-inhibitor combinations, carbapenems, fluoroquinolones, and aminoglycosides. We evaluated the clinical and microbiological characteristics of drug-resistant P. aeruginosa and MDRP strains that were isolated at Niigata University Hospital, Japan, from 2000 to 2004. We experienced an outbreak of MDRP in 2000, but colonization only was the main feature of the outbreak. Also, the isolation rate of MDRP has decreased since 2004; this reduction in the isolation rate seems to be a result of a move to newly built ward sections in 2001 and the establishment of an infection control team (ICT) in 2003.

The major methicillin-resistant Staphylococcus aureus(MRSA) distributed among hospitals in Japan is New York/Japan clone [multilocus sequence type 5 (ST5), agr type 2 and methicillin resistance locus type (SCC mec) II] which possesses both the toxic shock syndrome toxin 1 gene (tst) and staphylococcal enterotoxin C gene (sec). In this study, we collected 245 MRSA strains from four hospitals during 2001 to 2005 in Niigata, Japan, and analyzed tst and sec genes and SCC mec type among them. A total of 13 strains were further examined for their genotypes, virulence gene patterns and drug resistance. Among the 245 strains four tst sec genes patterns were observed; tst(+) sec(+) strains represented a majority of 86.5% and 9.4% were tst(-) sec(-). SCCmec typing revealed that 91.4% had type II, 4.1% type IV and 4.1% type I. Multilocus sequence typing (MLST) revealed that 10 of the 13 typed strains belonged to clonal complex 5 (7 had ST5 while 3 were single locus variants of ST5) with similar characteristics to the New York/Japan clone and possessed multi-drug resistance with high virulence gene content. The remaining 3 strains were ST8 (n=2) and ST91 (n=1). The ST91 strain had SCC mec IV and seemed to originate in the community, while ST8 strains exhibited SCC mec type I, which is distinct from community type IV. The data suggest that MRSA in hospitals in Niigata now mainly includes the New York/Japan clone (undergoing genomic divergence and clonal expansion) and other minor types (e.g. ST8) as well as the community type.

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) with Panton-Valentine leukocidin (PVL) genes is increasing worldwide. Nosocomial outbreak-derived (hospital-acquired) MRSA (HA-MRSA) in Japan in the 1980s was also largely PVL(+). PVL(+) HA-MRSA and CA-MRSA shared the same multi-locus sequence type (ST30) and methicillin resistance cassette (SCCmecIV), but were divergent in oxacillin resistance, spa typing, PFGE analysis or clfA gene analysis. PVL(+) HA-MRSA, which probably originated in PVL(+)S. aureus ST30, was highly adhesive (carrying cna and bbp genes), highly-toxic (carrying luk(PV) and sea genes) and highly drug-resistant. PVL(+) HA-MRSA was once replaced by other PVL(-) HA-MRSA (e.g., ST5), and is re-emerging as CA-MRSA.

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) was collected from children with bullous impetigo in 2003 and 2004. One strain collected in 2003 was Panton-Valentine leucocidin (PVL) positive. In 2004, a multiple-drug-resistant PVL(+) CA-MRSA strain was isolated from an athlete with a cutaneous abscess. These strains were analyzed by multilocus sequence typing, spa typing, agr typing, coagulase typing, staphylococcal cassette chromosome mec (SCCmec) typing, PCR assay for 30 virulence genes, drug susceptibility testing, pulsed-field gel electrophoresis, and for plasmids. The two Japanese PVL(+) CA-MRSA strains belonged to the globally extant ("pandemic") sequence type 30 (ST30) with SCCmec IV. A transmissible, multiple-drug resistance plasmid emerged in such ST30 strains. The PVL(-) CA-MRSA strains ("domestic" CA-MRSA) accumulated for bullous impetigo, exhibiting new genotypes. Hospital-acquired MRSA of ST91 (but not pandemic ST5) shared common features with the PVL(-) CA-MRSA strain.

Objective: In order to evaluate long-term toxicity of Combivir, we retrospectively reviewed clinical records of HIV-1 infected cases under treatment with Combivir-containing regimen and we analyzed the clinical data compared to other NRTIs-containing regimens., Study Design: A total of 55 patients who were on Combivir and 39 on a control regimen were examined., Results: After starting treatment with Combivir-containing regimens viral load and CD4(+) T-cell count improved as well as the control group. Rates of adverse events in Combivir group and ZDV (400 mg/day) + 3TC group were 50.9% (28/55) and 60% (12/20), respectively. Some of these Japanese patients who started Combivir regimen as a first-line HAART (primary Combivir group) showed some decrease in hemoglobin levels or neutrophil counts within 6 months. However, a significant recovery of these indices of hematological toxicities occurred in patients who continued the regimen for 18-24 months., Conclusion: Our findings suggest that the safety of 600 mg of ZDV is similar to 400 mg/day of ZDV and the existence of mechanisms that compensate for anemia and for the neutropenia associated with long-term use of Combivir.