Virological outcomes of various first-line ART regimens in patients harbouring HIV-1 E157Q integrase polymorphism: a multicentre retrospective study

BACKGROUND

Integrase strand transfer inhibitors (INSTIs) are recommended as first-line ART for people living with HIV (PLWH) in most guidelines. The INSTI-resistance-associated mutation E157Q, a highly prevalent (2%-5%) polymorphism of the HIV-1 (human immunodeficiency virus type 1) integrase gene, has limited data on optimal first-line ART regimens. We assessed the virological outcomes of various first-line ART regimens in PLWH with E157Q in real-world settings.

METHODS

A multicentre retrospective observational study was conducted on PLWH who underwent integrase genotypic drug-resistance testing before ART initiation between 2008 and 2019 and were found to have E157Q. Viral suppression (<50 copies/mL) rate at 24 and 48 weeks, time to viral suppression and time to viral rebound (≥100 copies/mL) were compared among the first-line ART regimens.

RESULTS

E157Q was detected in 167 (4.1%) of 4043 ART-naïve PLWH. Among them, 144 had available clinical data after ART initiation with a median follow-up of 1888 days. Forty-five started protease inhibitors + 2 NRTIs (PI group), 33 started first-generation INSTI (raltegravir or elvitegravir/cobicistat) + 2 NRTIs (INSTI-1 group), 58 started once-daily second-generation INSTI (dolutegravir or bictegravir) + 2 NRTIs (INSTI-2 group) and eight started other regimens. In the multivariate analysis, the INSTI-2 group showed similar or favourable outcomes compared with the PI group for viral suppression rates, time to viral suppression and time to viral rebound. Two cases in the INSTI-1 group experienced virological failure.

CONCLUSIONS

The general guideline recommendation of second-generation INSTI-based first-line ART for most PLWH is also applicable to PLWH harbouring E157Q.

Effect of voluntary human mobility restrictions on vector-borne diseases during the COVID-19 pandemic in Japan: A descriptive epidemiological study using a national database (2016 to 2021)

The coronavirus disease 2019 (COVID-19) pandemic not only encouraged people to practice good hygiene but also caused behavioral inhibitions and resulted reduction in both endemic and imported infectious diseases. However, the changing patterns of vector-borne diseases under human mobility restrictions remain unclear. Hence, we aimed to investigate the impact of transborder and local mobility restrictions on vector-borne diseases through a descriptive epidemiological study. The analysis was conducted using data from the National Epidemiological Surveillance of Infectious Diseases system in Japan. We defined the pre-pandemic period as the period between the 1st week of 2016 to the 52nd week of 2019 and defined the pandemic period as from the 1st week of 2020 to the 52nd week of 2021, with the assumption that human mobility was limited throughout the pandemic period. This study addressed 24 diseases among notifiable vector borne diseases. Datasets were obtained from weekly reports from the National Epidemiological Surveillance of Infectious Diseases, and the incidence of each vector-borne disease was examined. Interrupted time series analysis was conducted on the epidemic curves for the two periods. Between the pre- and post-pandemic periods, the incidence of dengue fever and malaria significantly decreased, which may be related to limited human transboundary mobility (p = 0.003/0.002). The incidence of severe fever with thrombocytopenia syndrome, scrub typhus, and Japanese spotted fever did not show changes between the two periods or no association with human mobility. This study suggests that behavioral control may reduce the incidence of new mosquito-borne diseases from endemic areas but may not affect tick-borne disease epidemics within an endemic area.

Association of demographics, HCV co-infection, HIV-1 subtypes and genetic clustering with late HIV diagnosis: a retrospective analysis from the Japanese Drug Resistance HIV-1 Surveillance Network

INTRODUCTION

Late diagnosis of the human immunodeficiency virus (HIV) is a major concern epidemiologically, socially and for national healthcare systems. Although the association of certain demographics with late HIV diagnosis has been reported in several studies, the association of other factors, including clinical and phylogenetic factors, remains unclear. In the present study, we conducted a nationwide analysis to explore the association of demographics, clinical factors, HIV-1 subtypes/circulating recombinant form (CRFs) and genetic clustering with late HIV diagnosis in Japan, where new infections mainly occur among young men who have sex with men (MSM) in urban areas.

METHODS

Anonymized data on demographics, clinical factors and HIV genetic sequences from 39.8% of people newly diagnosed with HIV in Japan were collected by the Japanese Drug Resistance HIV-1 Surveillance Network from 2003 to 2019. Factors associated with late HIV diagnosis (defined as HIV diagnosis with a CD4 count <350 cells/μl) were identified using logistic regression. Clusters were identified by HIV-TRACE with a genetic distance threshold of 1.5%.

RESULTS

Of the 9422 people newly diagnosed with HIV enrolled in the surveillance network between 2003 and 2019, 7752 individuals with available CD4 count at diagnosis were included. Late HIV diagnosis was observed in 5522 (71.2%) participants. The overall median CD4 count at diagnosis was 221 (IQR: 62-373) cells/μl. Variables independently associated with late HIV diagnosis included age (adjusted odds ratio [aOR] 2.21, 95% CI 1.88-2.59, ≥45 vs. ≤29 years), heterosexual transmission (aOR 1.34, 95% CI 1.11-1.62, vs. MSM), living outside of Tokyo (aOR 1.18, 95% CI 1.05-1.32), hepatitis C virus (HCV) co-infection (aOR 1.42, 95% CI 1.01-1.98) and not belonging to a cluster (aOR 1.30, 95% CI 1.12-1.51). CRF07_BC (aOR 0.34, 95% CI 0.18-0.65, vs. subtype B) was negatively associated with late HIV diagnosis.

CONCLUSIONS

In addition to demographic factors, HCV co-infection, HIV-1 subtypes/CRFs and not belonging to a cluster were independently associated with late HIV diagnosis in Japan. These results imply the need for public health programmes aimed at the general population, including but not limited to key populations, to encourage HIV testing.

Incidence of common infectious diseases in Japan during the COVID-19 pandemic

Recent reports indicate that respiratory infectious diseases were suppressed during the novel coronavirus disease-2019 (COVID-19) pandemic. COVID-19 led to behavioral changes aimed to control droplet transmission or contact transmission. In this study, we examined the incidence of common infectious diseases in Japan during the COVID-19 pandemic. COVID-19 data were extracted from the national data based on the National Epidemiological Surveillance of Infectious Diseases (NESID). Common infectious diseases were selected from notifiable infectious diseases under the NESID. The epidemic activity of the diseases during 2015-2020 was evaluated based on the Infectious Disease Weekly Reports published by the National Institute of Infectious Diseases. Each disease was then categorized according to the route of transmission. Many Japanese people had adopted hygienic activities, such as wearing masks and hand washing, even before the COVID-19 pandemic. We examined the correlation between the time-series of disease counts of common infectious diseases and COVID-19 over time using cross-correlation analysis. The weekly number of cases of measles, rotavirus, and several infections transmitted by droplet spread, was negatively correlated with the weekly number of cases of COVID-19 for up to 20 weeks in the past. According to the difference-in-differences analysis, the activity of influenza and rubella was significantly lower starting from the second week in 2020 than that in 2015-2019. Only legionellosis was more frequent throughout the year than in 2015-2019. Lower activity was also observed in some contact transmitted, airborne-transmitted, and fecal-oral transmitted diseases. However, carbapenem-resistant Enterobacteriaceae, exanthema subitum, showed the same trend as that over the previous 5 years. In conclusion, our study shows that public health interventions for the COVID-19 pandemic may have effectively prevented the transmission of most droplet-transmitted diseases and those transmitted through other routes.

Revised hospital antibiotic formulary reduces antimicrobial consumption and promotes a shift towards narrow-spectrum antibiotic usage

BACKGROUND

In Japan, the national action plan to adress antimicrobial resistance problems aimed to reduce the use of oral cephalosporins, quinolones, and macrolides per day per 1000 inhabitants by 50% from the levelin 2013 by 2020. The aim of this study was to evaluate the effects of a revised antibiotic formulary on in- and out-hospital oral antibiotic prescribing practices at a 600-bed university hospital.

METHOD

A retrospective before-and-after comparison study was conducted. All antimicrobial consumption data in the reviewed classes from 1 January 2013 to 31 December 2018, were extracted from the hospital database's electronic medical records. The data were measured in the defined daily dose and antibiotic use density (defined daily dose per 1000 patient-days).

RESULTS

The total oral antibiotic use densities for in-hospital prescriptions in 2013 and 2018 were 117.95 and 75.42, respectively, and 239.83 and 193.88, respectively, for out-hospital prescriptions. From 2013 to 2018, antibiotic use densities of second- and third-generation cephalosporins, macrolides and fluoroquinolones for in-hospital prescriptions changed annually by -49.00%, -92.67%, +0.49% and -48.19%, and out-hospital prescriptions of these antibiotics changed by +76.69%, -86.37%, -16.29% and -51.75%, over the same period. Penicillin prescriptions increased by 71.31% for in-hospital and 42.72% for out-hospital prescriptions over this period.

CONCLUSIONS

The revised hospital antibiotic formulary reduced total antibiotic consumption and increased the use of narrow-spectrum antibiotics for both in- and out-hospital prescriptions.

Clinical and bacterial features of Group B streptococci with reduced penicillin susceptibility from respiratory specimens: a case-control study

Streptococcus agalactiae (Group B Streptococcus, GBS) is an invasive pathogen that causes sepsis and meningitis among infants, elderly adults, and immunosuppressed patients. Generally, GBS is susceptible to penicillin; however, GBS with reduced penicillin susceptibility (PRGBS) has been reported. PRGBS are commonly isolated from respiratory specimens, but clinical features of patients with PRGBS remain unclear. In this case-control study, clinical features of patients with PRGBS and bacterial characteristics of these isolates from respiratory specimens were investigated. Patients with GBS at the University of the Ryukyus Hospital between January 2017 and June 2018 were retrospectively investigated. GBS were further classified into penicillin-susceptible GBS (PSGBS) and PRGBS using a drug susceptibility test. Moreover, serotypes, genotypes, and drug resistance genes of PRGBS isolates were determined. In total, 362 GBS were isolated, of which 46 were collected from respiratory specimens, which had the highest rate of PRGBS (24%). Compared to patients with PSGBS, those with PRGBS were more likely to have neuromuscular disease, poor performance status, risk of multidrug-resistant pathogen infection, prior pneumonia history within 1 year, and prior penicillin use within 1 year. Among eight PRGBS isolates, multilocus sequence typing revealed that five isolates were sequence type (ST) 358, two were ST3 and ST10, respectively, and one isolate was ST1404. All PRGBS isolates belonged to the ST1/ST19/ST10 group. This study reveals clinical characteristics of patients with PRGBS from respiratory specimens. Because invasive GBS infection cases are increasing, especially in the elderly, more attention should be paid to this infection.

Case Report: Ischemic Enterocolitis Associated with Coronavirus Disease 2019: Two Case Reports and a Review of the Literature

The COVID-19 pandemic has caused serious health and social concerns worldwide. Although the primary target of SARS-CoV-2 is the respiratory tract, SARS-CoV-2 infection also causes extrapulmonary symptoms. Previous articles have reported ischemic colitis in COVID-19 patients; however, information regarding its clinical manifestations and pathophysiology is limited. In this case report, we present two cases of ischemic enterocolitis in COVID-19 patients and review past case reports. Our literature review has shown that computed tomography rather than endoscopy was used for the diagnosis, and any region of the intestine was affected. Because the elevation of the D-dimer, which suggested a hypercoagulable state, was reported in most cases, we assumed that thrombosis at any level in the artery and vein was involved in the pathophysiology of COVID-19-associated enterocolitis. SARS-CoV-2-induced endotheliitis can cause both coarctation of the vessels and thrombosis; therefore, both patterns of ischemic colitis, occlusive and nonocclusive, may be involved in COVID-19-associated enterocolitis.

Case Report: Iliopsoas Hematoma during the Clinical Course of Severe COVID-19 in Two Male Patients

Anticoagulation plays a major role in reducing the risk of systematic thrombosis in patients with severe COVID-19. Serious hemorrhagic complications, such as intracranial hemorrhage, have also been recognized. However, intra-abdominal hemorrhage is under-recognized because of its rare occurrence, despite high mortality. Here, we discuss two cases of spontaneous iliopsoas hematoma (IPH) likely caused by anticoagulants during the clinical course of COVID-19. We also explored published case reports to identify clinical characteristics of IPH in COVID-19 patients. The use of anticoagulants may increase the risk of lethal IPH among COVID-19 patients becsuse of scarce data on optimal dosage and adequate monitoring of anticoagulant effects. Rapid diagnosis and timely intervention are crucial to ensure good patient outcomes.

Human immunodeficiency virus-associated pulmonary sarcoidosis in a Japanese man as a manifestation of immune reconstitution inflammatory syndrome

Asymptomatic pulmonary sarcoidosis can develop after starting antiretroviral therapy. The decision on whether to treat sarcoidosis with corticosteroids should be based on the disease severity.

Changes in serum concentration of rilpivirine in an HIV-infected patient treated with a combination therapy of hemodialysis and peritoneal dialysis

Background

To our knowledge, there are no preexisting reports concerning rilpivirine (RPV) removal by hemodialysis and peritoneal dialysis.

Case presentation

This study aimed to evaluate the effect of hemodialysis and peritoneal dialysis on plasma concentrations of RPV in a 45-year-old man infected with HIV and exhibiting end-stage renal disease (ESRD). The extraction ratio of RPV by hemodialysis was 4.5%. Plasma concentrations of RPV remained far above the protein-binding-adjusted inhibitory levels during a combination therapy of hemodialysis and peritoneal dialysis. Our results suggest minimal RPV removal via hemodialysis and peritoneal dialysis with no specific dosage adjustments required in an HIV-infected patient undergoing this combination therapy.

Conclusion

In conclusion, this study showed that RPV administered without dose adjustment resulted in steady-state plasma drug concentration in an HIV-infected patient treated with a combination therapy of hemodialysis and peritoneal dialysis.

Acute Hypertriglyceridaemia Caused by Tocilizumab in a Patient with Severe COVID-19

Treatment with tocilizumab (TCZ) to block interleukin-6 (IL-6) signalling is predicted to mitigate cytokine release syndrome (CRS) caused by coronavirus disease 2019 (COVID-19). However, the adverse effects of TCZ on patients with COVID-19 remain unclear. We herein report a patient with COVID-19 treated with TCZ who developed acute hypertriglyceridaemia. Despite favipiravir treatment, acute respiratory distress syndrome developed in a 45-year-old patient with COVID-19; thus, TCZ was initiated. The triglyceride levels greatly increased after TCZ administration. Physicians should consider the negative impact of TCZ on the lipid profile in patients with COVID-19, although COVID-19-induced CRS itself may be an aggravating factor.

Correlates of lifetime and past one-year HIV-testing experience among men who have sex with men in Japan

This study aimed to examine correlates of lifetime and past-year HIV testing among men who have sex with men (MSM) in Japan. A unique, anonymous online self-report survey was conducted in 2015. A total of 776 participants completed the survey and answered questions on sociodemographic information, HIV-testing experience, history of syphilis, experience talking about HIV, recognition of AIDS-related community-based organization (CBO) materials, and sex behaviors. HIV-testing experience and related factors were assessed for two groups: regional cities and Tokyo and Osaka. A Poisson regression analysis revealed that higher lifetime HIV testing was associated with older age, previous syphilis diagnosis, and experience talking about HIV. Moreover, higher HIV testing in the past year was associated with experience talking about HIV with friends and recognition of HIV-related CBO materials. Increased dissemination of HIV-related information provided by CBOs may, therefore, be an effective prevention policy intervention targeted at Japanese MSM to promote regular testing and maintain their interest in HIV issues.

Clinical Features of Human Metapneumovirus Pneumonia in Non-Immunocompromised Patients: An Investigation of Three Long-Term Care Facility Outbreaks

Background

Several studies have reported outbreaks due to human metapneumovirus (hMPV) in long-term care facilities (LTCF) for the elderly. However, most of these reports are epidemiological studies and do not investigate the clinical features of hMPV pneumonia.

Methods

Three independent outbreaks of hMPV occurred at separate LTCF for intellectually challenged and elderly residents. A retrospective evaluation of hMPV pneumonia and its clinical and radiological features was conducted using available medical records and data.

Results

In 105 hMPV infections, 49% of patients developed pneumonia. The median age of pneumonia cases was significantly higher than non-pneumonia cases (P < .001). Clinical manifestations of hMPV pneumonia included high fever, wheezing in 43%, and respiratory failure in 31% of patients. An elevated number of white blood cells as well as increased levels of C-reactive protein, creatine phosphokinase, and both aspartate and alanine transaminases was also observed among pneumonia cases. Evaluation of chest imaging revealed proximal bronchial wall thickenings radiating outward from the hilum in most patients.

Conclusions

The aforementioned characteristics should be considered as representative of hMPV pneumonia. Patients presenting with these features should have laboratory testing performed for prompt diagnosis.

Nationwide surveillance of bacterial respiratory pathogens conducted by the surveillance committee of Japanese Society of Chemotherapy, the Japanese Association for Infectious Diseases, and the Japanese Society for clinical microbiology in 2014: General view of the pathogens' antibacterial susceptibility

The nationwide surveillance on antimicrobial susceptibility of bacterial respiratory pathogens from the patients in Japan was conducted by Japanese Society of Chemotherapy, the Japanese Association for Infectious Diseases, and the Japanese Society for Clinical Microbiology in 2014. The isolates were collected from clinical specimens obtained from well-diagnosed adult patients with respiratory tract infections during the period between January 2014 and April 2015 by three societies. Antimicrobial susceptibility testing was conducted at the central reference laboratory according to the method recommended by Clinical Laboratory Standards Institute. Susceptibility testing was evaluated in 1534 strains (335 Staphylococcus aureus, 264 Streptococcus pneumoniae, 29 Streptococcus pyogenes, 281 Haemophilus influenzae, 164 Moraxella catarrhalis, 207 Klebsiella pneumoniae, and 254 Pseudomonas aeruginosa). Ratio of methicillin-resistant S. aureus was 43.6%, and those of penicillin-susceptible S. pneumoniae was 100%. Among H. influenzae, 8.2% of them were found to be β-lactamase-producing ampicillin-resistant strains, and 49.1% to be β-lactamase-non-producing ampicillin-resistant strains. Extended spectrum β-lactamase-producing K. pneumoniae and multi-drug resistant P. aeruginosa with metallo β-lactamase were 9.2% and 0.4%, respectively.

Do infections with disseminated Mycobacterium avium complex precede sweet's syndrome? A case report and literature review

Sweet's syndrome is reportedly associated with preceding nontuberculous mycobacterial infections (NTMIs). Here, we report on a systemic Mycobacterium intracellulare infection in a patient on corticoid therapy for Sweet's syndrome. Literature searches show that 69.1% of patients with Sweet's syndrome and NTMIs developed this syndrome later than NTMIs and 89.3% of them developed during the clinical course of a rapidly growing mycobacterial infection. The residual cases were associated with slow-growing mycobacteria (14.3%), but only three cases of Mycobacterium avium complex (MAC) infections before the onset of Sweet's syndrome have been reported, and all of them were caused by disseminated MAC disease. One of these cases developed during corticoid therapy for Sweet's syndrome, while another case had underlying diabetes mellitus. Hence, the occurrence of systemic MAC disease may be an inevitable consequence of long-term steroid use and underlying diseases. Literature searches also show that cervical lymphadenitis was a predominant symptom in NTMIs (90.5%). The present case did not have cervical lymphadenitis although the previously reported MAC cases did experience it. Therefore, lymphadenitis from NTMIs may be related to the pathogenesis of Sweet's syndrome. Hence, should a patient have systemic infection without lymphadenitis, it will be more difficult to clinically confirm that MAC disease is a predisposing factor for Sweet's syndrome.

Evaluation of Anyplex™ II RV16 and RB5 real-time RT-PCR compared to Seeplex® RV15 OneStep ACE and PneumoBacter ACE for the simultaneous detection of upper respiratory pathogens

This prospective study was performed to evaluate and compare the performance of the multiplex PCR Seeplex^® assays and Anyplex™ II assays. From May 2014 until April 2016, a total of 247 respiratory samples were collected in Okinawa, Japan. Multiple respiratory pathogens were detected in 37% of patients with positive results. The most prevalent pathogens were influenza A virus and respiratory syncytial virus B. Despite minor differences in capabilities, both the Seeplex^® assays and Anyplex™ II assays can be easily implemented in diagnostic or research laboratories to optimize the detection and management of respiratory pathogen induced diseases.

Nationwide surveillance of bacterial respiratory pathogens conducted by the surveillance committee of Japanese Society of Chemotherapy, the Japanese Association for Infectious Diseases, and the Japanese Society for Clinical Microbiology in 2012: General view of the pathogens' antibacterial susceptibility

The nationwide surveillance on antimicrobial susceptibility of bacterial respiratory pathogens from the patients in Japan was conducted by Japanese Society of Chemotherapy, Japanese association for infectious diseases and Japanese society for Clinical Microbiology in 2012. The isolates were collected from clinical specimens obtained from well-diagnosed adult patients with respiratory tract infections during the period between January and December in 2012 by three societies. Antimicrobial susceptibility testing was conducted at the central reference laboratory according to the method recommended by Clinical Laboratory Standard Institutes. Susceptibility testing was evaluated in 1236 strains (232 Staphylococcus aureus, 225 Streptococcus pneumoniae, 16 Streptococcus pyogenes, 231 Haemophilus influenzae, 147 Moraxella catarrhalis, 167 Klebsiella pneumoniae and 218 Pseudomonas aeruginosa). Ratio of methicillin-resistant S. aureus was 51.3%, and those of penicillin-intermediate S. pneumoniae was 0.4%. Among H. influenzae, 5.6% of them were found to be β-lactamase-producing ampicillin-resistant strains, and 37.2% to be β-lactamase-non-producing ampicillin-resistant strains. Extended spectrum β-lactamase-producing K. pneumoniae and multi-drug resistant P. aeruginosa with metallo β-lactamase were 4.2% and 3.2%, respectively. Continuous national surveillance is important to determine the actual situation of the resistance shown by bacterial respiratory pathogens to antimicrobial agents.

Pulmonary strongyloidiasis: assessment between manifestation and radiological findings in 16 severe strongyloidiasis cases

Background

Strongyloidiasis is a chronic parasitic infection caused by Strongyloides stercoralis. Severe cases such as, hyperinfection syndrome (HS) and disseminated strongyloidiasis (DS), can involve pulmonary manifestations. These manifestations frequently aid the diagnosis of strongyloidiasis. Here, we present the pulmonary manifestations and radiological findings of severe strongyloidiasis.

Methods

From January 2004 to December 2014, all patients diagnosed with severe strongyloidiasis at the University of the Ryukyus Hospital or affiliated hospitals in Okinawa, Japan, were included in this retrospective study. All diagnoses were confirmed by the microscopic or histopathological identification of larvae. Severe strongyloidiasis was defined by the presence of any of the following: 1) the identification of S. stercoralis from extra gastrointestinal specimens, 2) sepsis, 3) meningitis, 4) acute respiratory failure, or 5) respiratory tract hemorrhage. Patients were assigned to either HS or DS. Medical records were further reviewed to extract related clinical features and radiological findings.

Results

Sixteen severe strongyloidiasis cases were included. Of those, fifteen cases had pulmonary manifestations, eight had acute respiratory distress syndrome (ARDS) (53%), seven had enteric bacterial pneumonia (46%) and five had pulmonary hemorrhage (33%). Acute respiratory failure was a common indicator for pulmonary manifestation (87%). Chest X-ray findings frequently showed diffuse shadows (71%). Additionally, ileum gas was detected for ten of the sixteen cases in the upper abdomen during assessment with chest X-ray. While, chest CT findings frequently showed ground-glass opacity (GGO) in 89% of patients. Interlobular septal thickening was also frequently shown (67%), always accompanying GGO in upper lobes.

Conclusions

In summary, our study described HS/DS cases with pulmonary manifestations including, ARDS, bacterial pneumonia and pulmonary hemorrhage. Chest X-ray findings in HS/DS cases frequently showed diffuse shadows, and the combination of GGO and interlobular septal thickening in chest CT was common in HS/DS, regardless of accompanying pulmonary manifestations. This CT finding suggests alveolar hemorrhage could be used as a potential marker indicating the transition from latent to symptomatic state. Respiratory specimens are especially useful for detecting larvae in cases of HS/DS.

Etiological analysis and epidemiological comparison among adult CAP and NHCAP patients in Okinawa, Japan

BACKGROUND

Etiological epidemiology and diagnosis are important issues for CAP and NHCAP. Despite the availability of effective therapies, significant morbidity and mortality ensues.

METHODS

We retrospectively analyzed the etiology of 200 pneumonia patients at the University of the Ryukyus Hospital. Patients were categorized into CAP (n = 97) or NHCAP (n = 103), according to the Japanese Respiratory Society guidelines. Diagnoses were made using clinical tests including, Gram stain, bacterial culture, serum and urinary tests.

RESULTS

Pathogens were detected in 71% of patients, and identified as the source of infection in 52% (104/200). The majority of patients suffered from Streptococcus pneumoniae (32/200), Haemophilus influenzae (22/200), and Moraxella catarrhalis (16/200). Gram stain guided pathogen-oriented therapy decisions for 38 of 96 patients with unknown pathogens. Atypical pathogens were only diagnosed in CAP patients (n = 5). Severity of pneumonia was related to male sex (p = 0.006), and preexisting conditions, such as chronic heart failure (p < 0.001) and COPD (p < 0.001). Risk factors associated with increased length of stay included chronic heart failure, chronic renal failure, other pulmonary diseases and diabetes. Mortality for NHCAP patients was associated with lung cancer and bronchiectasis. CAP patients were more frequently admitted during winter months, while NHCAP patients were admitted during all other seasons. Seasonal patterns for individual pathogens could not be determined.

CONCLUSION

Gram staining remains useful to guiding diagnostics. Pathogens affecting CAP and NHCAP patients were not significantly different; as such, attention should be focused on the management of underlying conditions. Clinical outcomes were not affected by guideline discordant therapy.

The clinical and phylogenetic investigation for a nosocomial outbreak of respiratory syncytial virus infection in an adult hemato-oncology unit

Although many reports have already shown RSV outbreaks among hemato-oncology patients, genomic studies detecting similar RSV strains prior to an outbreak in the hospital are rare. In 2014, the University of the Ryukyus hospital hemato-oncology unit experienced, and successfully managed, a respiratory syncytial virus (RSV) nosocomial outbreak. During the outbreak investigation, genotyping and phylogenetic analysis was used to identify a potential source for the outbreak. Nasopharyngeal swabs were tested for RSV using three tests: (1) rapid antigen test (RAT); (2) reverse transcriptase polymerase chain reaction (PCR); or (3) quantitative PCR (RT-qPCR); a positive PCR reaction was considered a confirmed case of RSV. Phylogenetic analysis of the G protein was performed for outbreak and reference samples from non-outbreak periods of the same year. In total, 12 confirmed cases were identified, including 8 hemato-oncology patients. Patient samples were collected weekly, until all confirmed RSV cases returned RSV negative test results. Median time of suspected viral shedding was 16 days (n = 5, range: 8-37 days). Sensitivity and specificity of the RAT compared with RT-qPCR were 30% and 91% (n = 42). Phylogenetic analysis revealed nine genetically identical strains; eight occurring during the outbreak time period and one strain was detected 1 month prior. A genetically similar RSV detected 1 month before is considered one potential source of this outbreak. As such, healthcare providers should always enforce standard precautions, especially in the hemato-oncology unit.

Evaluation of the Lipid Concentrations after Switching from Antiretroviral Drug Tenofovir Disoproxil Fumarate/Emtricitabine to Abacavir Sulfate/Lamivudine in Virologically-suppressed Human Immunodeficiency Virus-infected Patients

Objective Recently, tenofovir disoproxil fumatate (TDF)-related side effects, such as renal nephrotoxicity and reduction of bone mineral density, have been reported. Consequently, increased switching from fixed-dose tablet TDF and emtricitabine (TDF/FTC) to abacavir and lamivudine (ABC/3TC) has occurred. Interestingly, while TDF has a lipid-lowering property, one of the ABC-related side effects is hyperlipidemia. Therefore, such switching could cause lipid elevation. To evaluate the change in lipid levels associated with switching from TDF/FTC to ABC/3TC in virologically-suppressed human immunodeficiency virus (HIV)-infected patients. Methods This is a retrospective, single-center study. We included the HIV-infected patients whose therapy included a drug switch from TDF/FTC to ABC/3TC between September 2009 and December 2012 at Ryukyu University Hospital. The exclusion criteria were HIV-RNA >40 copies/mL on the switching day, and a documented therapy change to a lipid-lowering agent or any other antiretroviral agents within 3 months before or after switching. We compared the low-density lipoprotein (LDL), high-density lipoprotein (HDL), total cholesterol (TC), and triglyceride (TG) levels before switching to three months after. Results A total of 18 patients met the inclusion criteria. The LDL, HDL, and TC levels significantly increased three months following the switch (p<0.05), with median (interquartile range) values of 17 (7, 32), 6 (2, 13), and 27 (10, 45) mg/dL, respectively. The TG values did not markedly change. Conclusion Switching from TDF/FTC to ABC/3TC resulted in significantly increased LDL, HDL, and TC levels.

A Novel Drug-Resistant HIV-1 Circulating Recombinant Form CRF76_01B Identified by Near Full-Length Genome Analysis

HIV-1 CRF01_AE and subtype B (B) have dominated and their different circulating recombinant forms (CRFs) have emerged in East and Southeast Asian countries. Here, we report a novel drug-resistant HIV-1 CRF. Five independent recombinant specimens exhibiting discordant subtype results for the gag, pol, and env sequences were isolated. These recombinants had the CRF01_AE (gag p17)/B (pol PR-RT and IN)/CRF01_AE (env C2-V3) pattern similar to CRF69_01B. Sequence analysis of four near full-length HIV-1 genomes revealed a unique phylogenetic cluster distinct from previously reported CRFs. Of the four recombinants, three shared an identical mosaic structure including seven breakpoints in the gag, pol, vif, and env regions, designated CRF76_01B. The one remaining recombinant had additional recombination breakpoints in the vpu region and exhibited another unique recombinant form composed of CRF76_01B and B. These findings provide important insight into the transmission dynamics of HIV-1 in Asia that may be important for its effective prevention.

An Epidemiological Analysis of Summer Influenza Epidemics in Okinawa

Objective This study evaluates the difference between winter influenza and summer influenza in Okinawa. Methods From January 2007 to June 2014, weekly rapid antigen test (RAT) results performed in four acute care hospitals were collected for the surveillance of regional influenza prevalence in the Naha region of the Okinawa Islands. Results An antigenic data analysis revealed that multiple H1N1 and H3N2 viruses consistently co-circulate in Okinawa, creating synchronized seasonal patterns and a high genetic diversity of influenza A. Additionally, influenza B viruses play a significant role in summer epidemics, almost every year. To further understand influenza epidemics during the summer in Okinawa, we evaluated the full genome sequences of some representative human influenza A and influenza B viruses isolated in Okinawa. Phylogenetic data analysis also revealed that multiple H1N1 and H3N2 viruses consistently co-circulate in Okinawa. Conclusion This surveillance revealed a distinct epidemic pattern of seasonal and pandemic influenza in this subtropical region.