MicroRNAs in infectious diseases: potential diagnostic biomarkers and therapeutic targets

MicroRNAs (miRNAs) are conserved, short, non-coding RNAs that play a crucial role in the post-transcriptional regulation of gene expression. They have been implicated in the pathogenesis of cancer and neurological, cardiovascular, and autoimmune diseases. Several recent studies have suggested that miRNAs are key players in regulating the differentiation, maturation, and activation of immune cells, thereby influencing the host immune response to infection. The resultant upregulation or downregulation of miRNAs from infection influences the protein expression of genes responsible for the immune response and can determine the risk of disease progression. Recently, miRNAs have been explored as diagnostic biomarkers and therapeutic targets in various infectious diseases. This review summarizes our current understanding of the role of miRNAs during viral, fungal, bacterial, and parasitic infections from a clinical perspective, including critical functional mechanisms and implications for their potential use as biomarkers and therapeutic targets.

Observation of the Exotic 0_{2}^{+} Cluster State in ^{8}He

We report here the first observation of the 0_{2}^{+} state of ^{8}He, which has been predicted to feature the condensatelike α+^{2}n+^{2}n cluster structure. We show that this state is characterized by a spin parity of 0^{+}, a large isoscalar monopole transition strength, and the emission of a strongly correlated neutron pair, in line with theoretical predictions. Our finding is further supported by the state-of-the-art microscopic α+4n model calculations. The present results may lead to new insights into clustering in neutron-rich nuclear systems and the pair correlation and condensation in quantum many-body systems under strong interactions.

Immunogenicity and Safety of Booster SARS-CoV-2 mRNA Vaccine Dose in Allogeneic Hematopoietic Stem Cell Transplantation Recipients

Allogeneic hematopoietic stem cell transplantation (HSCT) recipients are susceptible to severe outcomes of Coronavirus disease 2019 (COVID-19). Most guidelines recommend a fourth dose (ie, booster) of COVID-19 vaccine to reduce the infection risk, and observational studies are needed to determine the immunogenicity and safety of the booster dose in this population. The primary outcome was to determine the quantitative anti-receptor-binding domain (RBD) antibody titers after the fourth dose of the COVID-19 vaccine. The secondary outcomes included adverse effects and all-cause mortality. This single-group prospective cohort included allogeneic HSCT recipients age ≥18 years who received their fourth dose of COVID-19 mRNA vaccine between December 15, 2021, and August 2, 2022. We excluded patients with a history of COVID-19 diagnosis and those who received i.v. Ig within 21 days of antibody testing or rituximab within 6 months before study entry. We used regression models to determine the contributing factors significantly associated with post-fourth dose anti-RBD titer. Sixty-seven patients (median age, 59.5 years; IQR, 53.5 to 65.5 years; 33 males [61%]) received the fourth dose of vaccine, and 54 were included in the anti-RBD titer analysis. The median anti-RBD titers at 4 to 6 weeks after the third and fourth doses differed significantly (13,350 U/mL [IQR, 2618 to 34,740 U/mL] and 44,500 U/mL [IQR, 11,163 to 84,330 U/mL], respectively; P < .0001). In univariate analysis, the post-third dose anti-RBD titer (β = .70; 95% CI, .54 to .87; P < .001) and treatment with mycophenolate compounds (β = -1.05; 95% CI, -1.97 to -1.12; P = .03) significantly predicted the antibody response to the fourth dose. In multivariate analysis, the inverse association between treatment with mycophenolate compounds and the post-fourth dose anti-RBD antibody titer was not significant (β = -.57; 95% CI, -1.32 to .19; P = .14), whereas the significant association between the anti-RBD titers following the third and fourth doses did not change considerably (β = .66; 95% CI, .47 to .86; P < .001). The most frequent adverse event was vaccination site soreness (44%), followed by fatigue (16%), myalgia (4%), and headache (2%). No recipient experienced new or worsened preexisting graft-versus-host disease within 40 days of vaccination, and no patient died. Six patients (11%) developed breakthrough severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection not associated with hospitalization or severe outcomes. The fourth dose of the COVID-19 vaccine appears to be highly immunogenic and safe in allogeneic HSCT recipients. Further studies are needed to determine the neutralizing antibody titers against SARS-CoV-2 subvariants and the effectiveness and immunogenicity of bivalent vaccines in allogeneic HSCT recipients.

Predictive scoring system for distinguishing Stenotrophomonas maltophilia bacteremia from Pseudomonas aeruginosa bacteremia in patients with hematological malignancies

Difficulties in immediately distinguishing Stenotrophomonas maltophilia (SM) bacteremia from Pseudomonas aeruginosa (PA) bacteremia in the clinical setting can lead to treatment delay. We aimed to develop a scoring system to immediately distinguish SM bacteremia from PA bacteremia using clinical indicators. We enrolled cases of SM and PA bacteremia in adult patients with hematological malignancies between January 2011 and June 2018. The patients were randomized into derivation and validation cohorts (2:1), and a clinical prediction tool for SM bacteremia was developed and verified. In total, 88 SM and 85 PA bacteremia cases were identified. In the derivation cohort, the following independent predictors of SM bacteremia were identified: no evidence of PA colonization, antipseudomonal β-lactam breakthrough bacteremia, and central venous catheter insertion. We scored each of the three predictors according to their regression coefficient (2, 2, and 1, respectively). Receiver operating characteristic curve analysis confirmed the score's predictive performance, with an area under the curve of 0.805. The combined sensitivity and specificity (0.655 and 0.821) was highest with a cut-off value of 4 points. Positive and negative predictive values were 79.2% (19/24) and 69.7% (23/33), respectively. This novel predictive scoring system is potentially useful for distinguishing SM bacteremia from PA bacteremia, which would facilitate immediate administration of appropriate antimicrobial therapy.

Search for Dark-Matter-Nucleon Interactions via Migdal Effect with DarkSide-50

Dark matter elastic scattering off nuclei can result in the excitation and ionization of the recoiling atom through the so-called Migdal effect. The energy deposition from the ionization electron adds to the energy deposited by the recoiling nuclear system and allows for the detection of interactions of sub-GeV/c^{2} mass dark matter. We present new constraints for sub-GeV/c^{2} dark matter using the dual-phase liquid argon time projection chamber of the DarkSide-50 experiment with an exposure of (12 306±184)  kg d. The analysis is based on the ionization signal alone and significantly enhances the sensitivity of DarkSide-50, enabling sensitivity to dark matter with masses down to 40  MeV/c^{2}. Furthermore, it sets the most stringent upper limit on the spin independent dark matter nucleon cross section for masses below 3.6  GeV/c^{2}.

Search for Dark Matter Particle Interactions with Electron Final States with DarkSide-50

We present a search for dark matter particles with sub-GeV/c^{2} masses whose interactions have final state electrons using the DarkSide-50 experiment's (12 306±184)  kg d low-radioactivity liquid argon exposure. By analyzing the ionization signals, we exclude new parameter space for the dark matter-electron cross section σ[over ¯]_{e}, the axioelectric coupling constant g_{Ae}, and the dark photon kinetic mixing parameter κ. We also set the first dark matter direct-detection constraints on the mixing angle |U_{e4}|^{2} for keV/c^{2} sterile neutrinos.

Oxidative Stress Inhibits Endotoxin Tolerance and May Affect Periodontitis

Periodontal disease is caused by dysbiosis of the dental biofilm and the host inflammatory response. Various pathogenic factors, such as proteases and lipopolysaccharides (LPSs) produced by bacteria, are involved in disease progression. Endotoxin tolerance is a function of myeloid cells, which sustain inflammation and promote tissue regeneration upon prolonged stimulation by endotoxins such as LPS. The role of endotoxin tolerance is gaining attention in various chronic inflammatory diseases, but its role in periodontal disease remains elusive. Oxidative stress, one of the major risk factors for periodontal disease, promotes disease progression through various mechanisms, of which only some are known. The effect of oxidative stress on endotoxin tolerance has not yet been studied, and we postulated that endotoxin tolerance regulation may be an additional mechanism through which oxidative stress influences periodontal disease. This study aimed to reveal the effect of oxidative stress on endotoxin tolerance and that of endotoxin tolerance on periodontitis progression. The effect of oxidative stress on endotoxin tolerance was analyzed in vitro using peritoneal macrophages of mice and hydrogen peroxide (H₂O₂). The results showed that oxidative stress inhibits endotoxin tolerance induced by Porphyromonas gingivalis LPS in macrophages, at least partially, by downregulating LPS-elicited negative regulators of Toll-like receptor (TLR) signaling. A novel oxidative stress mouse model was established using SMP30KO mice incapable of ascorbate biosynthesis. Using this model, we revealed that oxidative stress impairs endotoxin tolerance potential in macrophages in vivo. Furthermore, gingival expression of endotoxin tolerance-related genes and TLR signaling negative regulators was decreased, and symptoms of ligature-induced periodontitis were aggravated in the oxidative stress mouse model. Our findings suggest that oxidative stress may contribute to periodontitis progression through endotoxin tolerance inhibition.

Formation and evolution of carbonaceous asteroid Ryugu: Direct evidence from returned samples

Samples of the carbonaceous asteroid Ryugu were brought to Earth by the Hayabusa2 spacecraft. We analyzed 17 Ryugu samples measuring 1 to 8 millimeters. Carbon dioxide-bearing water inclusions are present within a pyrrhotite crystal, indicating that Ryugu's parent asteroid formed in the outer Solar System. The samples contain low abundances of materials that formed at high temperatures, such as chondrules and calcium- and aluminum-rich inclusions. The samples are rich in phyllosilicates and carbonates, which formed through aqueous alteration reactions at low temperature, high pH, and water/rock ratios of <1 (by mass). Less altered fragments contain olivine, pyroxene, amorphous silicates, calcite, and phosphide. Numerical simulations, based on the mineralogical and physical properties of the samples, indicate that Ryugu's parent body formed ~2 million years after the beginning of Solar System formation.

Dose-Response Relationships between Diet Quality and Mortality among Frail and Non-Frail Older Adults: A Population-Based Kyoto-Kameoka Prospective Cohort Study

OBJECTIVES

Although better diet quality is inversely associated with mortality risk, the association between diet quality and mortality remains unclear in frail and non-frail older adults. Thus, we aimed to examine this association in older Japanese adults.

DESIGN

A prospective cohort study.

SETTING AND PARTICIPANTS

We used the data of 8,051 Japanese older adults aged ≥65 years in the Kyoto-Kameoka study.

MESUREMENTS

Dietary intake was estimated using a validated food frequency questionnaire. Diet quality was evaluated by calculating the adherence scores to the Japanese Food Guide Spinning Top (range, 0 [worst] to 80 [best]), which were stratified into quartiles. Frailty status was assessed using the validated self-administered Kihon Checklist (KCL) and the Fried phenotype (FP) model. Survival data were collected between February 15, 2012 and November 30, 2016. Statistical analysis was performed using the multivariate Cox proportional hazard analysis and the spline model.

RESULTS

During the median 4.75-year follow-up (36,552 person-years), we recorded 661 deaths. After adjusting for confounders, compared with the bottom adherence score quartile, the top quartile was associated with lower hazard ratio (HR) of mortality in frailty (HR, 0.73; 95% confidence interval [CI], 0.54-1.00) and non-frailty, as defined by the KCL (HR, 0.72; 95% CI, 0.52-1.01). In the spline model, regardless of frailty status defined by the KCL and FP model, adherence score showed a strongly dose-dependent inverse association with mortality up to approximately 55 points; however, no significant differences were observed thereafter. This association was similar to the results obtained in individuals with physical, cognitive, and depression as domains of KCL in the spline model.

CONCLUSIONS

Our findings demonstrate an L-shaped association between diet quality and mortality in both frail and non-frail individuals. This study may provide important knowledge for improving poor diet quality in older individuals with frailty or domains of frailty.

Expression of Vincristin-induced Peripheral Neuropathy Related to Different Administration Methods

Vincristine (VCR) is an important drug used in R-CHOP regimens for the treatment of non-Hodgkin's lymphoma. The purpose of this study was to examine whether the administration method affects the incidence of VCR-induced peripheral neuropathy. We investigated the ratio of VCR-induced peripheral neuropathy during rapid intravenous infusion and intravenous drip infusion. A total of 71 patients who had received six or more courses of R-CHOP from January, 2015 to December, 2016 at Komaki City Hospital and Ogaki Municipal Hospital were retrospectively investigated. Peripheral neuropathy was observed in 27/39 patients (69 %) and 24/32 (75 %) in rapid intravenous infusion and intravenous drip infusion of VCR, respectively (P = 0.79). Peripheral neuropathy was observed at a high frequency in this study. Additionally, there was no difference in frequency of peripheral neuropathy due to the difference in administration method. In both groups, the degree of peripheral neuropathy was grade 1 and grade 2 in most patients. However, in rapid intravenous infusion, grade 3 peripheral neuropathy was observed. Some cases required dose reduction and discontinuation in rapid intravenous infusion. In contrast, there were no discontinuing patients in the intravenous drip infusion. Therefore, it was suggested that intravenous drip infusion of VCR reduced serious peripheral neuropathy because the ratio requiring dose reduction and discontinuation was less than that in the rapid group. In conclusion, this study is informative as there are few reports focusing on the administration method of vincristine.

Adequate Protein Intake on Comprehensive Frailty in Older Adults: Kyoto-Kameoka Study

OBJECTIVES

Defining an adequate protein intake in older adults remains unresolved. We examined the association between calibrated protein intake and comprehensive frailty by sex in the Kyoto-Kameoka study.

DESIGN

Cross-sectional study of baseline data.

SETTING AND PARTICIPANTS

The study included 5679 Japanese participants aged 65 years or older.

METHODS

Calibration coefficients were estimated from food frequency questionnaires and 7-day dietary records as a reference. Comprehensive frailty was evaluated using the 25-item Kihon Checklist (KCL) and defined as a total KCL score of ≥7points. Sex-specific calibrated protein intakes were presented as % of energy, per kg of actual body weight (BW), and per kg of ideal BW.

RESULTS

Multiple logistic regression analysis showed that calibrated protein intake is inversely associated with comprehensive frailty. The association between protein intake and comprehensive frailty was also evaluated using curve fitting with non-linear regression, a weak U-shaped association was found in males and an L-shaped association in females. Men had a low prevalence of frailty at a calibrated protein intake of 15-17% energy from protein, 1.2 g/kg actual BW/day, or 1.4 g/kg ideal BW/day, and women had a low prevalence of frailty at 17-21% energy from protein or 1.6 g/kg ideal BW/day, with the prevalence of frailty remaining unchanged at higher protein intakes. Meanwhile, the inverse relationship between protein intake per ABW and frailty showed a gradual decrease at 1.4 g/kg ABW/day for protein in women.

CONCLUSIONS AND IMPLICATIONS

A non-linear relationship was found between calibrated protein intake and frailty, with a U-shaped association in men and an L-shaped association in women. Adequate protein intake in healthy Japanese older adults was higher than the current recommended daily allowance.

Identifying prognostic factors associated with overall survival in second-line paclitaxel plus ramucirumab treated human epidermal growth factor receptor 2-negative advanced/recurrent gastric cancer

This study aimed to identify the overall survival prolongation index in patients who received paclitaxel plus ramucirumab as second line chemotherapy for human epidermal growth factor receptor (HER) 2-negative advanced/ recurrent gastric cancer (AGC). We included 77 patients who underwent second line chemotherapy (paclitaxel plus ramucirumab) for AGC at our institution between January 2015 and September 2020. To determine factors associated with survival, univariate and multivariate analyses were performed, and hazard ratios and their 95% confidence intervals (95% CI) were calculated. In the multivariate analysis, grade ≥1 neutropenia (yes) and the number of anti-cancer drugs used (≥5) were independently and significantly associated with survival. Compared to the patients without grade ≥1 neutropenia, patients with grade ≥1 neutropenia had a survival hazard ratio of 0.455 (95% CI: 0.214-0.966; p = 0.040). The median second line treatment durations in patients with grade ≥1 neutropenia (n = 54) and in those without grade ≥1 neutropenia (n = 23) were 133 days (95% CI, 98-190 days) and 70 days (95% CI, 41-128 days), respectively (log-rank test, p = 0.026). This study demonstrated that AGC patients with initial neutropenia may benefit from paclitaxel plus ramucirumab therapy.

AB0180 A MULTICENTER SELF-CONTROLLED CASE SERIES STUDY INVESTIGATING THE PREVENTIVE EFFECT OF SULFASALAZINE AGAINST PNEUMOCYSTIS PNEUMONIA

Background:

An animal study revealed that sulfasalazine (SSZ) enhances Pneumocystis clearance from the lung by accelerating macrophage activity.[1] Although the preventive effect of SSZ on Pneumocystis pneumonia (PCP) in patients with rheumatoid arthritis (RA) is reported in case-control studies, some important confounders might remain unmeasured and distort the results. [2-3]. The self-controlled case series (SCCS) method involves only cases and controls fixed confounders automatically.[4]

Objectives:

To evaluate the prophylactic effect of SSZ against PCP in patients with RA, controlling unmeasurable confounders by the SCCS method.

Methods:

A retrospective study was conducted at five hospitals. Patients with RA who developed PCP between 2003 and 2019 were included. PCP was defined by the following criteria: (1) detection of Pneumocystis jirovecii in respiratory specimens by polymerase chain reaction; (2) clinical manifestations (pyrexia, dry cough, dyspnea, or hypoxia); (3) diffuse interstitial infiltrate on chest imaging; (4) absence of prophylaxis for PCP. Incidence rate ratio (IRR) for Pneumocystis pneumonia associated with sulfasalazine use was calculated by conditional Poisson regression.

Results:

We identified 48 episodes of PCP in 47 cases. Of these, 15 (31.9%) died. Thirty received SSZ in certain periods of their observations (Table 1). While 46 episodes of PCP developed in the period of 168.9 person-years without SSZ use, only one episode of PCP developed in the period of 103.7 person-years with SSZ use. SSZ use had a decreased risk of PJP (adjusted IRR 0.007, 95% CI <0.001-0.067) after adjusted for age group, the use of glucocorticoid, methotrexate, and tacrolimus, and the use of biologic agent or janus kinase inhibitor (Table 2).

Table 1.

Characteristic of the 47 patients enrolled in the study.

Male/female, n (%)14 (29.8)/33 (70.2)Observational period (years), median (IQR)72.0 (66.3-79.1)Lung disease, n (%)4.7 (1.4-9.5)Use of sulfasalazine, n (%)23 (48.9)Outcome of PCP, death, n (%)30 (63.8)Age at the onset of PCP (years), median (IQR)15 (31.9)

PCP, Pneumocystis pneumonia; IQR, interquartile range.

Table 2.

Unadjusted and adjusted incidence rate ratio for Pneumocystis pneumonia associated with sulfasalazine use.

Observation length (years)Episodes of PCP, n (%)Unadjusted IRR95% CI)Adjusted IRRa(% CI)Use of SSZ103.71 (2.1)0.010 (0.001-0.092)0.007 (<0.001-0.067)No use of SSZ168.947 (97.9)referencereference

IRR, incidence rate ratio; PCP, Pneumocystis pneumonia; SSZ, sulfasalazine.

Conclusion:

Our study demonstrated the preventive effect of SSZ against PCP with confounders controlled by the SCCS.

References:

[1]Wang, J., et al. Immune modulation with sulfasalazine attenuates immunopathogenesis but enhances macrophage- mediated fungal clearance during pneumocystis pneumonia. PLoS Pathog. 2010;19;6(8):e1001058.

[2]Nunokawa, T. et al. Prophylactic effect of sulfasalazine against Pneumocystis pneumonia in patients with rheumatoid arthritis: A nested case-control study. Semin. Arthritis Rheum. 2019;48(4):573-578.

[3]Nunokawa, T., et al. Effect of Sulfasalazine Use on the Presence of Pneumocystis Organisms in the Lung among Patients with Rheumatoid Arthritis: A Test-Negative Design Case-Control Study with PCR Tests. Mod. Rheumatol. 2019;29(3):436-440.

[4]Petersen, I., et al. Self controlled case series methods: an alternative to standard epidemiological study designs. BMJ. 2016;12;354:i4515.

Disclosure of Interests:

None declared

A multicenter cohort study of osimertinib compared with afatinib as first-line treatment for EGFR-mutated non-small-cell lung cancer from practical dataset: CJLSG1903

Background

FLAURA, the prospective trial of osimertinib as a first-line therapy compared with first-generation epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs), did not show superior survival benefit for osimertinib in either the subgroup of Asians or the subgroup with the L858R mutation. In addition, the superiority of osimertinib compared with second-generation EGFR-TKI is thus far unclear.

Patients and methods

We reviewed the clinical data of all consecutive patients who were treated with osimertinib or afatinib as first-line therapy between May 2016 and October 2019 from 15 institutions in Japan. We defined the groups based on first-line EGFR-TKI as the afatinib group and the osimertinib group. Outcomes included time to discontinuation of any EGFR-TKI (TD-TKI), overall survival (OS), and time to treatment failure, with propensity score analysis carried out as an exploratory analysis in the survival and subgroup analyses.

Results

A total of 554 patients were enrolled. Data on 326 patients in the osimertinib group, and 224 patients in the afatinib group were analyzed. TD-TKI adjusted by propensity score in the afatinib and osimertinib groups was 18.6 months (95% confidence interval 15.8 to 22.0) and 20.5 months (95% confidence interval 13.8 to not reached), respectively, without significant difference (P = 0.204). OS adjusted by propensity score favored the afatinib group with a significant difference (P = 0.018). Subgroup analysis with propensity score showed that patients with L858R and without brain metastasis had superior survival benefit with afatinib compared with osimertinib (P < 0.001).

Conclusions

TD-TKI in the afatinib group was not significantly prolonged compared with the osimertinib group in the practical data. In the exploratory analysis of patients with L858R-mutated non-small-cell lung cancer without brain metastasis, afatinib showed more benefit in OS over osimertinib.

•

The large-scale practical data of 550 patients who were treated with osimertinib or afatinib as first-line therapy were analyzed.

•

The superiority of osimertinib compared with afatinib could not be demonstrated in all populations.

•

Osimertinib therapy showed effectiveness in patients with brain metastasis.

•

Afatinib therapy showed potential benefit in patients with L858R mutation and without brain metastasis.

Clinical characteristics and drug susceptibility patterns of Corynebacterium species in bacteremic patients with hematological disorders

The aim of this study was to clarify the clinical and microbiological characteristics of Corynebacterium bacteremia in hematological patients. We retrospectively reviewed the medical records of patients with Corynebacterium bacteremia from April 2013 to June 2018. The causative Corynebacterium species were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Drug susceptibility tests were performed using the broth microdilution method recommended by the Clinical and Laboratory Standards Institute. In total, 147 cases of Corynebacterium bacteremia were identified during the study period. Corynebacterium striatum was the most frequent pathogen. Catheter-related bloodstream infection was diagnosed in 19.7% of all patients, and moderate/severe oral or severe gastrointestinal mucosal impairment was detected in 19.7%. Polymicrobial infection was found in about 20% of cases, with Enterococcus faecium being the most frequent isolate. The overall 30-day mortality was 34.7% (51/147). Multivariate analysis showed that E. faecium co-infection (odds ratio (OR) 9.3; 95% confidence interval (CI) 2.1-40), systemic corticosteroids (OR 3.6; 95% CI 1.4-8.9), other immunosuppressive drugs (OR 0.32; 95% CI 0.13-0.76), and a Pitt bacteremia score ≥4 (OR 12; 95% CI 3.9-40) were significant risk factors for overall 30-day mortality. The drug susceptibility rates for beta-lactam antimicrobial agents were quite low. All isolates were susceptible to glycopeptides and linezolid. However, some C. striatum isolates were resistant to daptomycin. Corynebacterium bacteremia can occur in the presence of several types of mucosal impairment. Our drug susceptibility data indicate that Corynebacterium bacteremia in hematological patients could be treated by glycopeptides or linezolid.

Quasifree Neutron Knockout Reaction Reveals a Small s-Orbital Component in the Borromean Nucleus ^{17}B

A kinematically complete quasifree (p,pn) experiment in inverse kinematics was performed to study the structure of the Borromean nucleus ^{17}B, which had long been considered to have a neutron halo. By analyzing the momentum distributions and exclusive cross sections, we obtained the spectroscopic factors for 1s_{1/2} and 0d_{5/2} orbitals, and a surprisingly small percentage of 9(2)% was determined for 1s_{1/2}. Our finding of such a small 1s_{1/2} component and the halo features reported in prior experiments can be explained by the deformed relativistic Hartree-Bogoliubov theory in continuum, revealing a definite but not dominant neutron halo in ^{17}B. The present work gives the smallest s- or p-orbital component among known nuclei exhibiting halo features and implies that the dominant occupation of s or p orbitals is not a prerequisite for the occurrence of a neutron halo.

Reverse Transcription Loop-Mediated Isothermal Amplification Assay-Based Infection Control Strategies for COVID-19 in a Hospital Under the State of Emergency in Tokyo, Japan in Spring 2020

Studies describing reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay-based infection control strategies (LAMP-based ICSs) for coronavirus disease 2019 (COVID-19) are limited. We reviewed the medical records of cases in which RT-LAMP was performed. Standard ICSs and LAMP-based ICSs were implemented during the study period. The strategies were intended to impose longer periods of infection control precautions (ICPs) for specific patients, such as those with a history of exposure to COVID-19 patients and/or bilateral ground glass opacities (bGGO) on chest computed tomography (CT). Of 212 patients, which included 13 confirmed COVID-19 patients in the diagnostic cohort, exposure to COVID-19 patients (P <0.0001) and chest CT bGGO (P = 0.0022) were identified as significant predictors of COVID-19. In the 173 hospitalized patients in which the results of the first RT-LAMP were negative, the duration of ICPs was significantly longer in patients with exposure to COVID-19 and/or a high clinical index of suspicion and patients with bGGO than in the remaining patients (P = 0.00046 and P = 0.0067, respectively). Additionally, no confirmed COVID-19 cases indicating nosocomial spread occurred during the study period. Establishing a comprehensive system that combines rational LAMP-based ICSs with standard ICSs might be useful for preventing nosocomial spread.

Stenotrophomonas maltophilia bloodstream infections in adult recipients of umbilical cord blood transplantation

Limited data are available on Stenotrophomonas maltophilia bloodstream infections (SM-BSIs) and the therapeutic efficacy of trimethoprim-sulfamethoxazole (SXT) against SM-BSI in umbilical cord blood transplant (uCBT) recipients. Medical and microbiological records of adult patients who received uCBTs between December 2008 and December 2015 at Toranomon Hospital (Tokyo, Japan) were reviewed. The efficacy and safety of SXT were evaluated only for recipients who were treated with ≥7 days of intravenous SXT for SM-BSI (evaluation cohort). Of 561 uCBT recipients, 34 developed SM-BSI. Diabetes mellitus (P = .005) and age ≥ 60 years (P = .013) were significant independent risk factors for SM-BSI. Moreover, SM-BSI was identified as an independent risk factor for all-cause mortality up to 100 days following uCBT (P = .025). Of the 34 recipients with SM-BSI, 24 were treated with an intravenous SXT-containing regimen (iSXT-CR). Septic shock (P = .0021), pneumonia (P = .011), neutropenia (P = .0015), and systemic steroid administration (P = .018) were identified as significant independent risk factors for 7-day crude mortality. The evaluation cohort included nine recipients. Doses of SXT were 2.4 to 6.9 mg/kg/day of the trimethoprim component. Of the nine recipients, five developed SM-BSI during the pre-engraftment phase. The 30-day crude-mortality rate and clinical cure rate of the cohort were 22% and 67%, respectively. Only one of the nine recipients experienced significant neutrophil toxicity. In this study, the epidemiology of SM-BSI in uCBT recipients was determined and its negative impact on survival was demonstrated. A low- to moderate-dose iSXT-CR appeared to be a tolerable and important therapeutic option for SM-BSI in the uCBT setting, including during the pre-engraftment phase.

Association between severe neutropenia and progression-free survival in patients with advanced or recurrent breast cancer treated with palbociclib

This study aimed to clarify the relationship between neutropenia and progression-free survival (PFS) under palbociclib treatment for advanced/recurrent breast cancer and the risk factors for severe neutropenia. We retrospectively identified 37 patients who received palbociclib for advanced breast cancer at Ogaki Municipal Hospital (Ogaki, Japan) between April 2018 and June 2020. Kaplan-Meier log-rank test was used to compare PFS (mild [neutrophil count 1,000-2,000/mm 3 ] versus severe [neutrophil count <500-1,000/mm³]). Multivariate analysis was performed to evaluate the relationships between baseline patient characteristics and severe neutropenia development. There were three, four, 25, and five cases with grade 1, 2, 3, and 4 neutropenia, respectively. Median PFS in patients who developed severe neutropenia (n = 30) and those who did develop mild neutropenia (n = 7) was 176 days (range: 62-894 days) and 91 days (range: 19-384 days), respectively (log-rank test, p = 0.005). Severe neutropenia was independently associated with pre-treatment neutrophil count (odds ratio: 27.700; p =0.007). Severe neutropenia is more likely to occur with a pre-treatment neutrophil count of less than 3,680 mm³. Neutropenia prolongs PFS under palbociclib treatment, suggesting management of AEs and patient education as highly important, especially to prevent drug interruption/dose reduction of palbociclib due to these AEs.

Characteristics of gram-negative bacteremia during febrile neutropenia among allogeneic hematopoietic stem cell transplant recipients on levofloxacin prophylaxis

The aim of this study is to clarify the characteristics of gram-negative bacteremia (GNB), including extended-spectrum β-lactamase (ESBL)-producing pathogens, among allogeneic hematopoietic stem cell transplant (allo-HSCT) recipients on levofloxacin (LVFX) prophylaxis. A retrospective analysis on GNB at the first episode of febrile neutropenia (FN) was conducted among allo-HSCT recipients (age ≥ 20 years) on 500 mg/day of oral LVFX prophylaxis. Epidemiological and microbiological features of GNB were investigated and compared between the inappropriate and appropriate empiric therapy groups. In total, FN occurred in 414 allo-HSCT cases, and bacteremia at the first episode of FN occurred in 169 cases. Overall, 29 GNB cases were documented, and the causative organisms identified were Escherichia coli in 21 cases (including 10 ESBLs), Klebsiella pneumoniae in 2, Pseudomonas aeruginosa in 2, and other in 4. The crude 30-day mortality rate was not significantly different among cases of GNB (6.9%), gram-positive bacteremia (GPB) (7.1%), or non-bacteremia (5.4%; P = 0.78). Cefepime (CFPM) was administered in all cases in the inappropriate empiric therapy group, and all causative organisms were ESBL-producing E. coli (ESBL-EC). All patients in the inappropriate empiric therapy group had a low Pitt bacteremia score (≤ 2). Thirty-day mortality did not differ significantly between the inappropriate and appropriate empiric therapy groups (1/10 vs. 1/15, P = 0.61). In conclusion, GNB was not a significant cause of death. In LVFX breakthrough ESBL-EC bacteremia among allo-HSCT recipients, the administration of CFPM as empiric therapy did not lead to significantly poor prognosis. Empiric CFPM administration might be an acceptable strategy.

Efficacy and outcomes of balloon pulmonary angioplasty in elderly vs non-elderly chronic thromboembolic pulmonary hypertension patients

Introduction

Balloon pulmonary angioplasty (BPA) has been reported as an effective and safe treatment for patients with chronic thromboembolic pulmonary hypertension (CTEPH). However, its safety and efficacy in elderly patients remains unknown.

Purpose

We investigated the effect of BPA on hemodynamics and respiratory parameters, functional capacity, and short- and long-term outcome in elderly patients.

Methods

From November 2012 to May 2018, 141 consecutive CTEPH patients who underwent BPA in a single university hospital were enrolled (age: 65 [54.5–74] years old, WHO functional class [WHO-FC] II/III/IV; 35/96/10). Patients were divided into two groups according to the age; elderly (≥75 years, N=32) and young groups (&lt;75 years, N=109). Hemodynamics (right-sided heart catheterization), biomarkers (brain natriuretic peptide), respiratory function (spirometry and diffusion capacity measurement), and functional capacity (6-minute walk distance [6MWD] and WHO-FC) were evaluated at baseline and 1-year post BPA. Procedure-related complications (in hospital death, use of percutaneous cardiopulmonary support [PCPS], and pulmonary injury) and all cause death during the follow up period were also assessed.

Results

At baseline, although elderly group had less severe hemodynamics (mPAP: 33.1±6.7 vs 39.0±11.8 mmHg, p&lt;0.05), they had poor exercise capacity and reduced pulmonary diffusion capacity, compared with young group (6MWD: 264.6±101.3 vs 369.7±105.2 m, %DLco: 42.0±12.0 vs 50.2±12.7%, all p&lt;0.05). BPA improved hemodynamics, biomarkers, exercise capacity, and pulmonary diffusion capacity in both elderly and young groups (all p&lt;0.05). There was no in-hospital death or use of PCPS in both groups, although the incidence of pulmonary injury was higher in elderly group (14.3% vs 5.3%, p&lt;0.01). Under the normalized hemodynamics 1-year after BPA in both groups, exercise capacity and pulmonary diffusion capacity were worse in the elderly group than young groups (p&lt;0.01). The incidence of all-cause death in the follow up period was higher in elderly group, all of which were due to non-pulmonary hypertension (PH)-related death (p&lt;0.01).

Conclusion

BPA was effective in improving hemodynamics and respiratory parameters and functional capacity, in associated with no critical complication, regardless of the age. Elderly patients who were treated with BPA were associated with higher incidence of non-PH-related death.

Changes of mean PAP in the two groups

Funding Acknowledgement

Type of funding source: None

De-escalation/discontinuation of oxygen-therapy and medication is feasible and safe in chronic thromboembolic pulmonary hypertension patients treated with balloon pulmonary angioplasty

Introduction

There has been increasing evidence of the efficacy of balloon pulmonary angioplasty (BPA) in improving the hemodynamics, exercise capacity, and biomarkers of patients with chronic thromboembolic pulmonary hypertension (CTEPH). However, there is no consensus on the adjustment of home oxygen therapy (HOT) and pulmonary hypertension (PH)-specific medications after BPA in patients with CTEPH.

Purpose

We aimed to examine the current status of the de-escalation/discontinuation of HOT and PH-specific medications post-BPA, and clarify its effect on subsequent hemodynamics, biomarkers, and long-term clinical outcomes.

Methods and results

From November 2012 to July 2019, 134 consecutive CTEPH patients who underwent BPA at a single university hospital were enrolled (age; 63.6±13.4 years, female; n=87 [64.9%], WHO functional class [WHO-FC] II/III/IV; 33/92/9). Hemodynamic data, functional capacity (6-minute walk distance and WHO-FC), biomarkers (brain natriuretic peptide [BNP] and high-sensitivity troponin T [hs-TropT]), and respiratory function were evaluated at baseline, immediately and 1 year post-BPA. Clinical outcomes (all-cause death and heart failure [HF] admission) were also assessed during the follow up period. The total number of sessions was 6.3±2.0, and the number of target vessels was 14.3±2.0. Mean pulmonary arterial pressure decreased from 37.8±11.2 to 20.4±5.1 mmHg 1-year after BPA (p&lt;0.01). The proportion of patients who required HOT (at rest or on exertion) and combination medical therapy (≥2 PH-specific medications) decreased 1 year post-BPA (from 59.0% to 7.5%, and from 41.8% to 10.4%, respectively; Figure). Among 79 patients who required HOT during daytime, 64 patients (81.0%) discontinued HOT just after BPA completion. Among 56 patients who required combination medical therapy, 29 (51.8%) discontinued combination therapy. Baseline factors influencing the continuation of HOT and combination medical therapy post-BPA were almost identical (i.e. lower exercise capacity and pulmonary diffusion capacity, and worse hemodynamics). Results showed that discontinuation of HOT and combination medical therapy did not affect the maintenance of improved hemodynamics and levels of BNP and hs-TropT, and no adverse clinical outcomes (all-cause death and HF hospitalization) were observed during 1 year post-BPA.

Conclusions

Most CTEPH patients discontinued HOT and PH-specific combination medical therapy after BPA, which was not associated with the deterioration of hemodynamics, functional capacity, or biomarkers. No adverse long-term outcomes were observed. De-escalation/discontinuation of HOT and PH-specific combination medical therapy after BPA is feasible and safe for patients with CTEPH.

De-escalation of HOT and medical therapy

Funding Acknowledgement

Type of funding source: None

Safety of bronchoscopy in patients with malignant hematologic disorders

Background

Factors affecting the safety of bronchoscopy in patients with malignant hematologic disorders have not been well described. We evaluated the safety of bronchoscopy and describe factors affecting its complication rate in such patients.

Methods

Between January 2009 and December 2018, 316 bronchoscopies in 282 patients with malignant hematologic disorders and pulmonary infiltrates were performed at our institution. The bronchoscopic procedure used and its complications were evaluated.

Results

The most common underlying disease was acute myeloid leukemia (134/282 patients, 47.5%). Platelet transfusion was performed the day before or the day of bronchoscopy in 42.4%, supplemental oxygen was administered before the procedure in 23.1%, and midazolam was used in 74.4%. Thirty-five bronchoscopies (11.1%) were complicated by hemoptysis and 7 patients developed pneumothorax, 4 of whom required thoracic drainage. Two patients (0.6%) were intubated within 48 h of the procedure and prolonged oxygen desaturation (> 48 h) occurred in 3.8%. Multivariate analysis showed that only use of midazolam significantly reduced the risk of prolonged oxygen desaturation (hazard ratio 0.28, 95% confidence interval 0.09–0.85, p = 0.03). Transbronchial lung biopsy significantly increased the risk of hemoptysis (hazard ratio 10.40, 95% confidence interval 4.18–25.90, p = 0.00), while use of midazolam significantly reduced the risk (hazard ratio 0.31, 95% confidence interval 0.14–0.73, p = 0.01).

Conclusions

Bronchoscopy is relatively safe in patients with malignant hematologic disorders. Caution and judicious use of sedatives may improve the patient’s procedural tolerance and lower complications.

AB0268 HUMAN T-CELL LEUKAEMIA VIRUS TYPE 1 MAY INVALIDATE T-SPOT.TB RESULTS AMONG RHEUMATOID ARTHRITIS PATIENTS: A RETROSPECTIVE OBSERVATIONAL STUDY

Background:

In clinical rheumatology, interferon-γ release assays (IGRAs) have been reported as a useful diagnostic test for latent tuberculosis infection (LTBI) before beginning the administration of biologics such as anti-TNF therapies (1). CD4-positive T cells are the main target in Human T-cell leukaemia virus type 1 (HTLV-1) infection. Several reports suggest that the reaction of tuberculin skin test (TST) is attenuated in HTLV-1-positive individuals compared with that in HTLV-1-negative individuals (2). However, it remains unclear whether IGRAs are reliable for detecting TB infection among HTLV-1-positive RA patients.

Objectives:

The present study aimed to investigate the usefulness of the T-SPOT.TBassay in HTLV-1-positive RA patients. In addition, the association between the existence of IFN-γ producing T cells and HTLV-1 proviral loads (PVLs) in HTLV-1-positive RA patients was analysed on the basis of the T-SPOT.TBassay results.

Methods:

We reviewed the medical records of 75 HTLV-1-negative and 29 HTLV-1-positive RA patients were suspected cases of LTBI and evaluated using the T-SPOT.TBassay as a clinical practice from April 2012 to July 2019. The results of T-SPOT.TBwere collected from medical records, retrospectively. Peripheral blood samples were obtained from HTLV-1-positive RA patients for the analysis of HTLV-1 PVLs values. The study protocol was approved by the research ethics committees of our hospitals.

Results:

Approximately 55% of the HTLV-1-positive RA patients showed invalid results for the T-SPOT.TBassay (p < 0.0001); the cause of invalid results was a spot-forming count of >10 spots in the negative controls of the T-SPOT.TBassay among HTLV-1-positive RA patients. Among HTLV-1-positive RA patients, HTLV-1 PVL values were significantly higher in 16 patients who showed invalid results than in 13 patients who did not (p = 0.003). There were no between-group differences in female patient ratio, age, RA disease activity and therapeutic regimens. IFN-γ producing cells were detected in the peripheral blood of HTLV-1-positive RA patients without stimulation with TB-specific antigens.

Conclusion:

The incidence of invalid results for the T-SPOT.TBassay has been reported to be as low as 0.6% (3). The results of this assay for screening of LTBI in HTLV-1-positive RA patients should be interpreted with caution. Furthermore, our results show that an increase in IFN-γ producing T cell numbers due to HTLV-1 infection in RA patients may affect the pathogenesis of RA.

References:

[1]Iannone, F., et al.J. Rheumatol. Suppl.91, 41-46 (2014).

[2]Tachibana, N., et al.Int. J. Cancer42, 829-831 (1988).

[3]Rego, K., et al.Tuberculosis (Edinb.)108, 178-185 (2018).

Acknowledgments:

We would like to thank Dr Yuki Hashikura and Ms Yuki Kaseda of the University of Miyazaki for their technical support in this work. We would also like to acknowledge Ms Yumiko Kai at the Institute of Rheumatology, Zenjinkai Shimin-no-Mori Hospital, for her help in data management.

A part this work was supported by a grant from the Practical Research Project for Rare/Intractable Diseases of the Japan Agency for Medical Research and Development (Grant No. JP19ek0109356), a Health and Labor Sciences Research Grant on Rare and Intractable Diseases from the Ministry of Health, Labor and Welfare of Japan (Grant No. 19FC1007), and a Grant-in-Aid for Clinical Research from Miyazaki University Hospital.

Disclosure of Interests:

Kunihiko Umekita Paid instructor for: Astellas Pharma Inc. Chugai Pharma Inc. Tanabe-Mitsubishi Pharma Inc., Speakers bureau: Bristol-Myers Squibb, Yayoi Hashiba: None declared, Risa Kudou: None declared, Shunichi Miyauchi: None declared, Masatoshi Kimura: None declared, Motohiro Matsuda: None declared, Chihiro Iwao: None declared, Yumi Kariya: None declared, Takeshi Kawaguchi: None declared, Katoko Takajo: None declared, Koushou Iwao: None declared, Yuuki Rikitake: None declared, Ichiro Takajo: None declared, Toshihiko Hidaka Paid instructor for: Astellas Pharma Inc. Chugai Pharma Inc. Tanabe-Mitsubishi Pharma Inc., Speakers bureau: Astellas Pharma Inc. Chugai Pharma Inc. Tanabe-Mitsubishi Pharma Inc., Akihiko Okayama: None declared

Positive-Parity Linear-Chain Molecular Band in ^{16}C

An inelastic excitation and cluster-decay experiment ^{2}H(^{16}C,^{4}He+^{12}Be or ^{6}He+^{10}Be)^{2}H was carried out to investigate the linear-chain clustering structure in neutron-rich ^{16}C. For the first time, decay paths from the ^{16}C resonances to various states of the final nuclei were determined, thanks to the well-resolved Q-value spectra obtained from the threefold coincident measurement. The close-threshold resonance at 16.5 MeV is assigned as the J^{π}=0^{+} band head of the predicted positive-parity linear-chain molecular band with (3/2_{π}^{-})^{2}(1/2_{σ}^{-})^{2} configuration, according to the associated angular correlation and decay analysis. Other members of this band were found at 17.3, 19.4, and 21.6 MeV based on their selective decay properties, being consistent with the theoretical predictions. Another intriguing high-lying state was observed at 27.2 MeV which decays almost exclusively to ^{6}He+^{10}Be(∼6  MeV) final channel, corresponding well to another predicted linear-chain structure with the pure σ-bond configuration.

Continuity and efficacy of real-world use of azacitidine

Long-term azacitidine (AZA) treatment is necessary for its maximal therapeutic effect. This study examined the continuity and efficacy of AZA treatment in real-world use. We conducted a retrospective study in 38 patients who had completed AZA treatment at the Ogaki Municipal Hospital between April 2011 and August 2019. The median number of AZA received cycles was 4. The number of AZA treatment cycles received was 1-3 cycles in 15 (39.5%), 4-6 cycles in 15 (39.5%), and ≥ 7 cycles in 8 (21.1%). The most common reason for discontinued AZA treatment was infection. Overall response rate was 33.3% in patients with discontinued AZA use (< 4 cycles) and 56.5% in patients with continued AZA (≥ 4). Median overall survival (OS) was 124 (15-529) days and 391 (132-2,825) days in the respective groups (p<0.01). The presence of peripheral blood blasts (PBs) was a prognostic factor for continuation of treatment (p =0.03). Discontinued AZA treatment due to infection (p <0.01), and PBs (p =0.03) were unfavourable prognostic factors for OS. Long-term AZA use is beneficial for improvement and survival. Infection control and presence of PBs were important factors for continuing AZA. These data support the idea of long-term continued treatment with AZA for optimal benefit to patients.

Matrix-assisted laser desorption ionization-time of flight mass spectrometry can be used to identify Helicobacter cinaedi

We examined the applicability of Matrix-assisted laser desorption ionization-time of flight mass spectrometry using 54 Helicobacter cinaedi isolates from humans. In all 54 isolates, MALDI-TOF MS detected H. cinaedi as the best match organism. Our findings suggest that MALDI TOF-MS can be used effectively to identify H. cinaedi.

Cost-effectiveness and safety of palbociclib and everolimus for treating advanced and recurrent breast cancer

This retrospective study compares the economic superiority of palbociclib versus everolimus for advanced and recurrent breast cancer. Furthermore, we investigated the safety and treatment continuity of palbociclib and everolimus regimens. Expected costs were calculated based on data from patients with advanced and recurrent breast cancer who were treated with palbociclib and everolimus. The progression-free survival (PFS) from the PALOMA-3 clinical trial and BOLERO-2 clinical trial was used to evaluate the therapeutic efficacy of the regimens. The cost-effectiveness ratio of each chemotherapy agent was calculated by dividing the expected cost by the progression-free survival (PFS). The cost-effectiveness ratio per month was JPY 391,551.3/PFS for palbociclib and JPY 488,690.5/PFS for everolimus (p=0.627). The incremental cost-effectiveness ratio per month of everolimus to palbociclib was JPY 100,133.7/PFS. For patients receiving everolimus, adverse drug reactions included stomatitis (77.3%), rash (59.1%) and leukopenia (59.1%). For patients receiving palbociclib, neutropenia (69.2%), leukopenia (69.2%) and anemia (30.8%) occurred. In terms of discontinuation owing to adverse events (AEs), pneumonitis, thrombocytopenia, edema, fatigue, and neutropenia were experienced in the everolimus group. The cost-effectiveness of everolimus and palbociclib are equivalent, but since the prevalence of AEs is high in patients receiving everolimus, its AE management is important.

Oral function and vertical jump height among healthy older people in Japan

OBJECTIVE

Vertical jump height and oral function affect the general muscle condition. This study aimed to evaluate the association between vertical jump height and oral function among healthy older individuals.

BASIC RESEARCH DESIGN

Cross-sectional analytic study.

PARTICIPANTS

231 independent older people (mean age, 74.4 ± 5.6 years) who participated in the Kyoto Elders Physical Fitness Measurement Research Project. Individuals with partial or complete edentulousness who did not use a prosthetic device or complained of oral/maxillofacial pain were excluded from the study.

INTERVENTIONS

Grip strength was measured using a Smedley Hand Dynamometer. To measure masticatory performance, the participants were instructed to chew a gummy jelly on their habitual chewing side (left or right) for 20 s. Occlusal force, contact area, and pressure were also assessed.

MAIN OUTCOME MEASURES

The outcome variable was vertical jump height. The predictor variables were physical status (age, body mass index, and grip strength), oral status (number of present teeth and denture use), and oral function (masticatory performance, occlusal force, occlusal contact area, occlusal pressure, and tongue pressure). These relationships were evaluated with univariate analysis, and then multiple regression analysis was performed with age as the covariate for each male and female participant.

RESULTS

Vertical jump height was significantly associated with grip strength in both men and women. Moreover, in women, it was associated with masticatory performance, occlusal force, and occlusal contact area.

CONCLUSIONS

Vertical jump height was closely associated with oral function among healthy older women.

Risk Factors for Recurrent Helicobacter cinaedi Bacteremia and the Efficacy of Selective Digestive Decontamination With Kanamycin to Prevent Recurrence

Background

Previous studies suggest that Helicobacter cinaedi can cause recurrent bacteremia. In this study, we elucidated the risk factors for recurrent H. cinaedi bacteremia and explored the efficacy of selective digestive decontamination (SDD) as a preventive measure.

Methods

We retrospectively reviewed the medical records of patients with H. cinaedi bacteremia between March 2009 and December 2016 at 2 Japanese hospitals.

Results

We identified 168 patients with H. cinaedi bacteremia. Bacteremia recurred in 34 patients. The 100-day cumulative incidence rate of recurrent bacteremia was 18.7%. In univariate analysis of factors associated with recurrent bacteremia, anticancer chemotherapy (hazard ratio [HR], 3.75; 95% confidence interval [CI], 1.86-7.58; P < .001), systemic steroids (HR, 3.79; 95% CI, 1.70-8.45; P = .0011), and hematological malignancy (HR, 3.18; 95% CI, 1.64-6.19; P < .001) were detected. Multivariate analysis indicated that anticancer chemotherapy (HR, 2.47; 95% CI, 1.19-5.12; P = .015) and systemic steroids (HR, 2.40; 95% CI, 1.03-5.61; P = .044) were the independent risk factors. Of the 168 patients, 47 received SDD. According to Gray's test, SDD might have reduced the rate of recurrence but this was not statistically significant (HR, 0.46; 95% CI, 0.18-1.18; P = .11). However, in a proportional hazard modeling analysis, SDD reduced the rate of recurrence (HR, 0.36; 95% CI, 0.13-1.00; P = .050).

Conclusions

The 100-day cumulative incidence of recurrent H. cinaedi bacteremia was 18.7%. Anticancer chemotherapy and systemic steroids were independent risk factors for recurrent bacteremia. SDD is a potential strategy for reducing the recurrence.

P1259Right atrial low voltage zone as a novel predictor of sinus node dysfunction in patients with non-paroxysmal atrial fibrillation

Background

Although sinus node dysfunction (SND) coexists with atrial fibrillation (AF) in some cases, SND in patients with Non-paroxysmal AF (Non-PAF) could not be estimated in conventional electrophysiological study.

Atrial low voltage zone (LVZ), which may be surrogate for atrial fibrosis, is although reported to present in patients with Non-PAF, the association between SND and right atrial LVZ (RA-LVZ) has not been fully evaluated. The aim of the present study was to assess the relationship between SND and RA-LVZ in patients with Non-PAF.

Method

Eighty-six Non-PAF patients underwent high density voltage mapping of right atrium (RA) during AF before ablation procedure. We defined LVZ as that with electrogram amplitude <0.1 mV in order to delineate strongly damaged area in RA. We evaluated the surface are of the RA-LVZ in Non-PAF patients with and without SND.

Results

Twenty-seven of 86 patients (31.4%) presented with SND after AF termination. There were no significant differences between patients with and without SND in variables such as age, sex, AF duration, left atrial diameter, and left ventricular ejection fraction. The mean value of RA-LVZ of all the patients was 12.1±11.4%, and RA-LVZ was significantly larger in patients with SND than in those without SND (22.8±14.6 vs 7.2±4.2%; P<0.001). In multivariate logistic regression analysis for the incidence of subsequent pacemaker implantation (PMI), only RA-LVZ was a significant predictor of subsequent PMI (odd ratio 1.306; 95% confidence interval 1.159 - 1.473; P<0.001). Receiving-operating characteristic curve for PMI following ablation procedure indicated cut-off value 10.5% for RA-LVZ with 85.2% sensitivity and 88.1% specificity (area under curve = 0.924, P<0.001). Kaplan-Meier analysis of the incidence of PMI after AF termination showed that freedom from pacemaker implantation was significantly better in patients with RA-LVA <10.5% than in those with RA-LVZ ≥10.5% (log-rank test; P<0.001).

Conclusions

Broad RA-LVZ measured during AF was strongly associated with SND and PMI after AF termination in patients with Non-PAF. Evaluation of RA-LVZ during AF could be a potential target in predicting SND requiring PMI in patients with Non-PAF.