Adverse effects of tamoxifen treatment on bone mineral density in premenopausal patients with breast cancer: a systematic review and meta-analysis

BACKGROUND

It is well known that adjuvant tamoxifen treatment for breast cancer in postmenopausal women decreased bone loss. However, the effects of adjuvant tamoxifen therapy on bone mineral density (BMD) in premenopausal patients with breast cancer remains uncertain. Tamoxifen would have a potential impact of premenopausal BMD on health. The aim of this meta-analysis was to assess this in premenopausal women with primary breast cancer.

METHODS

Through April 2020, studies reporting BMD changes of lumbar spine or hip in premenopausal women with primary breast cancer treated with adjuvant tamoxifen and tamoxifen plus chemotherapy or ovarian function suppression (OFS) were collected from EMBASE and PubMed. The meta-analysis was performed using random effects model of the standardized mean difference (SMD) of BMD in patients.

RESULTS

A total of 1432 premenopausal patients were enrolled in eight studies, involving 198 patients treated with tamoxifen alone in three studies. After a 3-year median follow-up, adjuvant tamoxifen decreased the lumbar spinal and hip BMD by as much as an SMD of -1.17 [95% confidence interval (CI); -1.58 to -0.76)] and -0.66 (95% CI, -1.55 to 0.23), respectively. In subgroup analysis in patients treated adjuvant tamoxifen and tamoxifen plus chemotherapy or OFS according to follow-up duration, the bone change of < 3 years follow-up group was -0.03 SMD (95% CI, -0.47 to 0.41) and that of ≥ 3 years follow-up group was -1.06 SMD (95% CI, -1.48 to -0.64). Compared with patients who received tamoxifen alone, patients who received combination therapy with chemotherapy or OFS showed lesser bone loss at the lumbar spine.

CONCLUSIONS

Our meta-analysis demonstrated that adjuvant tamoxifen therapy in premenopausal patients caused bone loss after 3 years of follow-up, especially at the lumbar spines. For a definite evaluation of the adverse effects of tamoxifen on bone, it is necessary to accumulate more relevant studies.

Stimulative piezoelectric nanofibrous scaffolds for enhanced small extracellular vesicle production in 3D cultures

Small extracellular vesicles (sEVs) have great promise as effective carriers for drug delivery. However, the challenges associated with the efficient production of sEVs hinder their clinical applications. Herein, we report a stimulative 3D culture platform for enhanced sEV production. The proposed platform consists of a piezoelectric nanofibrous scaffold (PES) coupled with acoustic stimulation to enhance sEV production of cells in a 3D biomimetic microenvironment. Combining cell stimulation with a 3D culture platform in this stimulative PES enables a 49 fold increase in the production rate per cell with minimal deviations in particle size and protein composition compared with standard 2D cultures. We find that the enhanced sEV production is attributable to the activation and upregulation of crucial sEV production steps through the synergistic effect of stimulation and the 3D microenvironment. Moreover, changes in cell morphology lead to cytoskeleton redistribution through cell matrix interactions in the 3D cultures. This in turn facilitates intracellular EV trafficking, which impacts the production rate. Overall, our work provides a promising 3D cell culture platform based on piezoelectric biomaterials for enhanced sEV production. This platform is expected to accelerate the potential use of sEVs for drug delivery and broad biomedical applications.

Alcohol and the risk of all-cause death, atrial fibrillation, ventricular arrhythmia, and sudden cardiac arrest

The risk of having atrial fibrillation (AF) is associated with alcohol intake. However, it is not clear whether sudden cardiac arrest (SCA) and ventricular arrhythmia (VA) including ventricular tachycardia, flutter, or fibrillation have similar associations with alcohol. We aimed to evaluate the association of alcohol intake with all-cause death, new-onset AF, VA, and SCA using single cohort with a sufficient sample size. A total of 3,990,373 people without a prior history of AF, VAs, or SCA was enrolled in this study based on nationwide health check-up in 2009. We classified the participants into four groups according to weekly alcohol consumption, and evaluated the association of alcohol consumption with each outcome. We observed a significant association between mild (hazard ratio [HR] = 0.826; 95% confidence interval [CI] = 0.815-0.838) to moderate (HR = 0.930; 95% CI = 0.912-0.947) drinking with decreased risk of all-cause mortality. However heavy drinking (HR = 1.108; 95% CI = 1.087-1.129) was associated with increased all-cause death. The risk of new-onset AF was significantly associated with moderate (HR = 1.129; 95% CI = 1.097-1.161) and heavy (HR = 1.298; 95% CI = 1.261-1.337) drinking. However, the risk of SCA showed negative association with all degrees of alcohol intake: 20% (HR = 0.803; 95% CI = 0.769-0.839), 15% (HR = 0.853; 95% CI = 0.806-0.902), and 8% (HR = 0.918; 95% CI = 0.866-0.974) lower risk for mild, moderate, and heavy drinkers, respectively. Mild drinking was associated with reduced risk of VA with moderate and heavy drinking having no associations. In conclusion, the association between alcohol and various outcomes in this study were heterogeneous. Alcohol might have different influences on various cardiac disorders.

Predicting postoperative lung function using ventilation SPECT/CT in patients with lung cancer

Background

Single-photon emission computed tomography/computed tomography (SPECT/CT) has the advantage of assessing regional lung function. We aimed to investigate the potential of ventilation (SPECT/CT) for predicting postoperative lung function in patients with lung cancer.

Methods

This retrospective study included consecutive patients with lung cancer who underwent lobectomy, preoperative ventilation, and perfusion SPECT/CT between January 2020 and December 2021. The percentage of predicted postoperative forced expiratory volume in 1 s (ppoFEV1%) and the percentage of predicted postoperative diffusion capacity of the lung for carbon monoxide (ppoDLCO%) were calculated from the % counts of each scan based on anatomical segments for lobar function. Correlation tests were performed between the predicted lung function values and actual ppoFEV1% and ppoDLCO%.

Results

Among the 47 patients, 29 men and 18 women aged 67.5±9.6 years were included. Moreover, 46 ventilation and 41 perfusion SPECT/CT scans were obtained. The pulmonary function on ventilation SPECT/CT strongly correlated with perfusion SPECT/CT (correlation coefficient r=0.939 for ppoFEV1%, P<0.001; r=0.938 for ppoDLCO%, P<0.001). Both ppoFEV1% and ppoDLCO% values obtained from the ventilation and perfusion scans strongly correlated with postoperative FEV1% and DLCO% (correlation coefficient, r=0.774 and r=0.768 for ventilation; r=0.795 and r=0.751 for perfusion, each P<0.001).

Conclusions

Ventilation SPECT/CT was comparable to perfusion SPECT/CT in predicting postoperative lung function.

Association of temporal change in body mass index with sudden cardiac arrest in diabetes mellitus

BACKGROUND

Underweight imposes significant burden on cardiovascular outcomes in patients with diabetes mellitus. However, less is known about the impact of serial change in body weight status measured as body mass index (BMI) on the risk of sudden cardiac arrest (SCA). This study investigated the association between SCA and temporal change in BMI among patients with diabetes mellitus.

METHODS

Based on Korean National Health Insurance Service database, participants with diabetes mellitus who underwent health examination between 2009 and 2012 and had prior health examination data (four years ago, 2005-2008) were retrospectively analyzed. BMI was measured at baseline (2005-2008) and 4-year follow-up health examination (2009-2012). Patients were classified in four groups according to the body weight status and its temporal change: sustained non-underweight, sustained underweight, previous underweight, and newly developed underweight. Primary outcome was defined as occurrence of SCA.

RESULTS

A total of 1,355,746 patients with diabetes mellitus were included for analysis, and SCA occurred in 12,554 cases. SCA was most common in newly developed underweight (incidence rate = 4.45 per 1,000 person-years), followed by sustained underweight (incidence rate = 3.90), previous underweight (incidence rate = 3.03), and sustained non-underweight (incidence rate = 1.34). Adjustment of covariates resulted highest risk of SCA in sustained underweight (adjusted hazard ratio = 2.60, 95% confidence interval [2.25-3.00], sustained non-underweight as a reference), followed by newly developed underweight (2.42, [2.15-2.74]), and previous underweight (2.12, [1.77-2.53]).

CONCLUSIONS

In diabetes mellitus, sustained underweight as well as decrease in body weight during 4-year follow-up imposes substantial risk on SCA. Recovery from underweight over time had relatively lower, but yet increased risk of SCA. Both underweight and dynamic decrease in BMI can be associated with increased risk of SCA.

Etanercept treatment for pediatric toxic epidermal necrolysis induced by deflazacort: a case report and literature review

Toxic epidermal necrolysis (TEN) is a life-threatening mucocutaneous disorder commonly caused by drugs. TEN is often treated with corticosteroids, intravenous immunoglobulin (IVIG), or cyclosporine; however, the efficacy of these treatments is controversial. Etanercept (a TNF-α antagonist) was proven to decrease skin-healing time in a randomized clinical trial. Herein, we report the case of a 44-month-old boy who developed TEN due to deflazacort as the probable culprit drug and was successfully treated with etanercept. The patient presented to the emergency department complaining of erythematous maculopapular rashes and vesicles all over the face and body, with vesicles on the hands, feet, and trunk. Symptoms started 4 days before presentation, with edema of the upper lip, which progressed to erythematous macules over the body. He was started on deflazacort for nephrotic syndrome 21 days before the visit. Approximately 20% of the body surface area (BSA) was covered by vesicular lesions. Under the diagnosis of Steven Johnson syndrome/TEN, deflazacort was discontinued, and intravenous dexamethasone (1.5 mg/kg/day), a 5-day course of IVIG (0.4 mg/kg/day), and cyclosporine (3 mg/kg/day) were administered. The lesions seemed to be stationary for 3 days, but on the 6th day of hospitalization, when IVIG was discontinued, the vesicular lesions progressed to approximately 60% of the BSA. Etanercept 0.8 mg/kg was administered subcutaneously. Lesions stopped progressing, and bullous lesions started epithelialization. However, on the 15th day, around 30% of the BSA was still involved; thus, a second dose of etanercept was administered. No acute or sub-acute complications were observed. In conclusion, the use of etanercept in children with TEN that is not controlled with conventional therapy is both effective and safe.

Association of typical atrial flutter and cavotricuspid isthmus ablation on clinical recurrence after cryoballoon ablation for atrial fibrillation

Typical atrial flutter commonly occurs in patients with atrial fibrillation (AF). Limited information exists regarding the effects of concurrent atrial flutter on the long-term outcomes of rhythm control. This study investigated the association between concurrent typical atrial flutter and cavotricuspid isthmus (CTI) ablation and the recurrence of atrial arrhythmia. The data were obtained from a multicenter registry of cryoballoon ablation for AF (n = 2,689). Patients who were screened for typical atrial flutter were included in the analysis (n = 1,907). All the patients with typical atrial flutter underwent CTI ablation. The primary endpoint was the late recurrence of atrial arrhythmia, including AF, atrial flutter, and atrial tachycardia. Among the 1,907 patients, typical atrial flutter was detected in 493 patients (25.9%). Patients with concurrent atrial flutter had a lower incidence of persistent AF and a smaller size of the left atrium. Patients with atrial flutter had a significantly lower recurrence rate of atrial arrhythmia (19.7% vs. 29.9%, p < 0.001). In patients with atrial flutter, the recurrence rate of atrial tachycardia or atrial flutter was more frequent (7.3% vs. 4.7%, p = 0.028), but the recurrence rate of AF was significantly lower (17.0% vs. 29.4%, p < 0.001). Atrial flutter has been identified as an independent predictor of the primary endpoint (adjusted hazard ratio, 0.704; 95% confidence interval, 0.548-0.906; p = 0.006). Typical atrial flutter in patients with AF may serve as a positive marker of the recurrence of atrial arrhythmia, and performing CTI ablation in this population is associated with a reduced likelihood of AF recurrence. Performing routine screening and ablation procedures for coexisting atrial flutter may improve the clinical outcomes of AF.

Identification of concealed cardiomyopathy using next-generation sequencing-based genetic testing in Korean patients initially diagnosed with idiopathic ventricular fibrillation

AIMS

Idiopathic ventricular fibrillation (IVF) is a disease in which the cause of ventricular fibrillation cannot be identified despite comprehensive clinical evaluation. This study aimed to investigate the clinical yield and implications of genetic testing for IVF.

METHODS AND RESULTS

This study was based on the multi-centre inherited arrhythmia syndrome registry in South Korea from 2014 to 2017. Next-generation sequencing-based genetic testing was performed that included 174 genes previously linked to cardiovascular disease. A total of 96 patients were clinically diagnosed with IVF. The mean age of the onset was 41.2 ± 12.7 years, and 79 patients were males (82.3%). Of these, 74 underwent genetic testing and four (5.4%) of the IVF probands had pathogenic or likely pathogenic variants (each having one of MYBPC3, MYH7, DSP, and TNNI3). All pathogenic or likely pathogenic variants were located in genes with definite evidence of a cardiomyopathy phenotype, either hypertrophic cardiomyopathy or arrhythmogenic right ventricular cardiomyopathy.

CONCLUSION

Next-generation sequencing-based genetic testing identified pathogenic or likely pathogenic variants in 5.4% of patients initially diagnosed with IVF, suggesting that genetic testing with definite evidence genes of cardiomyopathy may enable molecular diagnosis in a minority of patients with IVF. Further clinical evaluation and follow-up of patients with IVF with positive genotypes are needed to unveil concealed phenotypes, such as the pre-clinical phase of cardiomyopathy.

Clinical and Genetic Features of Korean Inherited Arrhythmia Probands

BACKGROUND AND OBJECTIVES

Inherited arrhythmia (IA) is a more common cause of sudden cardiac death in Asian population, but little is known about the genetic background of Asian IA probands. We aimed to investigate the clinical characteristics and analyze the genetic underpinnings of IA in a Korean cohort.

METHODS

This study was conducted in a multicenter cohort of the Korean IA Registry from 2014 to 2017. Genetic testing was performed using a next-generation sequencing panel including 174 causative genes of cardiovascular disease.

RESULTS

Among the 265 IA probands, idiopathic ventricular fibrillation (IVF) and Brugada Syndrome (BrS) was the most prevalent diseases (96 and 95 cases respectively), followed by long QT syndrome (LQTS, n=54). Two-hundred-sixteen probands underwent genetic testing, and 69 probands (31.9%) were detected with genetic variant, with yield of pathogenic or likely pathogenic variant as 6.4%. Left ventricular ejection fraction was significantly lower in genotype positive probands (54.7±11.3 vs. 59.3±9.2%, p=0.005). IVF probands showed highest yield of positive genotype (54.0%), followed by LQTS (23.8%), and BrS (19.5%).

CONCLUSIONS

There were significant differences in clinical characteristics and genetic yields among BrS, LQTS, and IVF. Genetic testing did not provide better yield for BrS and LQTS. On the other hand, in IVF, genetic testing using multiple gene panel might enable the molecular diagnosis of concealed genotype, which may alter future clinical diagnosis and management strategies.

Cancer coping self-efficacy, symptoms and their relationship with quality of life among cancer survivors

PURPOSE

Cancer coping self-efficacy refers to an individual's confidence in dealing with challenges from cancer-related events, and a positive association with quality of life (QoL) has been demonstrated. Considering unresolved physical and psychological symptoms at the survivorship phase, which are known to worsen QoL, the association between cancer coping self-efficacy and QoL needs to be evaluated controlling for known contributing factors of QoL. This study aimed to describe cancer survivors' cancer coping self-efficacy, symptoms and their relationship with QoL.

METHODS

A descriptive correlational study was conducted. Participants were cancer survivors who completed intended treatment except for hormone therapy (N = 240). Cancer coping self-efficacy, symptoms, and QoL were measured. To evaluate the association of cancer survivors' cancer coping self-efficacy with QoL, correlation and multiple regression analysis were conducted.

RESULTS

Cancer coping self-efficacy demonstrated a significant positive association with QoL. Symptoms had a significant negative association with QoL. Fully active cancer survivors demonstrated significantly better QoL than those with functional deterioration. Self-efficacy for using spiritual coping had a significant positive association with QoL, along with symptoms and functional status, which explained 37.5% of QoL.

CONCLUSIONS

Cancer survivors' QoL was related to spiritual coping self-efficacy, symptoms and functional status. Improving spiritual coping self-efficacy and managing symptoms reflecting survivors' functional status need to be integrated into survivorship care.

βPix Guanine Nucleotide Exchange Factor Regulates Regeneration of Injured Peripheral Axons

Axon regeneration is essential for successful recovery after peripheral nerve injury. Although growth cone reformation and axonal extension are crucial steps in axonal regeneration, the regulatory mechanisms underlying these dynamic processes are poorly understood. Here, we identify βPix (Arhgef7), the guanine nucleotide exchange factor for Rac1 GTPase, as a regulator of axonal regeneration. After sciatic nerve injury in mice, the expression levels of βPix increase significantly in nerve segments containing regenerating axons. In regrowing axons, βPix is localized in the peripheral domain of the growth cone. Using βPix neuronal isoform knockout (NIKO) mice in which the neuronal isoforms of βPix are specifically removed, we demonstrate that βPix promotes neurite outgrowth in cultured dorsal root ganglion neurons and in vivo axon regeneration after sciatic nerve crush injury. Activation of cJun and STAT3 in the cell bodies is not affected in βPix NIKO mice, supporting the local action of βPix in regenerating axons. Finally, inhibiting Src, a kinase previously identified as an activator of the βPix neuronal isoform, causes axon outgrowth defects in vitro, like those found in the βPix NIKO neurons. Altogether, these data indicate that βPix plays an important role in axonal regrowth during peripheral nerve regeneration.

Impact of pulmonary artery pressure on recurrence after catheter ablation in patients with atrial fibrillation

Background

The pulmonary veins play a major role in the pathogenesis of atrial fibrillation (AF) and may be affected by cardiac remodeling due to pulmonary vascular dysfunction. It remains to be determined whether pulmonary artery pressure (PAP) is associated with the recurrence of AF after radiofrequency catheter ablation (RFCA).

Methods

Consecutive patients with paroxysmal and persistent AF who underwent RFCA, including wide circumferential pulmonary vein isolation, were analyzed. Systolic PAP was measured using transthoracic echocardiography, and clinical outcomes were compared between patients with PAP <35 mmHg and those with PAP ≥35 mmHg.

Results

Among 2,379 patients (mean age 56.7 ± 10.6 years, 77% men), 1,893 (79.6%) had PAP <35 mmHg and 486 (20.4%) had PAP ≥35 mmHg. During the median follow-up of 25.4 months, in patients with paroxysmal AF (n = 1,294), the recurrence rate was significantly greater in the PAP ≥35 mmHg group than in the PAP <35 mmHg group (35.1% vs. 23.8%, log-rank p = 0.008). However, in patients with persistent AF (n = 1,085), the recurrence rate was not significantly different between the two groups (52.2% vs. 49.7%, log-rank p = 0.409). Multivariate analysis using Cox regression showed that PAP ≥35 mmHg was significantly associated with clinical recurrence (hazard ratio 1.19, 95% confidence interval 1.02-1.40, p = 0.027).

Conclusion

This study showed that a higher PAP was associated with an increased risk of recurrence after RFCA in patients with paroxysmal AF, suggesting a mechanism by which a pulmonary vascular pathology may cause impairment of the pulmonary veins and remodeling of the left atrium.

Prediction of Amyloid β-Positivity with both MRI Parameters and Cognitive Function Using Machine Learning

Purpose

To investigate the MRI markers for the prediction of amyloid β (Aβ)-positivity in mild cognitive impairment (MCI) and Alzheimer's disease (AD), and to evaluate the differences in MRI markers between Aβ-positive (Aβ [+]) and -negative groups using the machine learning (ML) method.

Materials and Methods

This study included 139 patients with MCI and AD who underwent amyloid PET-CT and brain MRI. Patients were divided into Aβ (+) (n = 84) and Aβ-negative (n = 55) groups. Visual analysis was performed with the Fazekas scale of white matter hyperintensity (WMH) and cerebral microbleeds (CMB) scores. The WMH volume and regional brain volume were quantitatively measured. The multivariable logistic regression and ML using support vector machine, and logistic regression were used to identify the best MRI predictors of Aβ-positivity.

Results

The Fazekas scale of WMH (p = 0.02) and CMB scores (p = 0.04) were higher in Aβ (+). The volumes of hippocampus, entorhinal cortex, and precuneus were smaller in Aβ (+) (p < 0.05). The third ventricle volume was larger in Aβ (+) (p = 0.002). The logistic regression of ML showed a good accuracy (81.1%) with mini-mental state examination (MMSE) and regional brain volumes.

Conclusion

The application of ML using the MMSE, third ventricle, and hippocampal volume is helpful in predicting Aβ-positivity with a good accuracy.

Association between low-density lipoprotein cholesterol and sudden cardiac arrest in people with diabetes mellitus

BACKGROUND

Dyslipidemia measured as low-density lipoprotein (LDL)-cholesterol is an established risk factor of cardiovascular disease, which is more pronounced in diabetes population. Less is known about the association of LDL-cholesterol level and sudden cardiac arrest (SCA) risk in diabetes mellitus patients. This study investigated the association of LDL-cholesterol level and SCA risk in diabetes population.

METHODS

This study was based on Korean National Health Insurance Service database. Patients who received general examination from 2009 to 2012 and diagnosed as type 2 diabetes mellitus were analyzed. Primary outcome was defined as SCA event identified with International Classification of Disease code.

RESULTS

A total of 2,602,577 patients were included, with total follow-up duration of 17,851,797 person * year. Mean follow-up duration was 6.86 years, and 26,341 SCA cases were identified. Overall incidence of SCA was highest in the lowest LDL-cholesterol group (< 70 mg/dL) and decreased in a linear manner as LDL-cholesterol rises, till 160 mg/dL. Adjustment of covariates resulted in U-shape association, with highest risk of SCA in the highest LDL-cholesterol group (≥ 160 mg/dL) followed by lowest LDL-cholesterol group (< 70 mg/dL). In subgroup analysis, U-shape association between SCA risk and LDL-cholesterol was more pronounced in male, non-obese people, and those who did not use statins.

CONCLUSIONS

In people with diabetes, the association between SCA and LDL-cholesterol level was U-shaped with highest and lowest LDL-cholesterol group having higher risk of SCA than others. Low LDL-cholesterol level can be a surrogate marker for increased risk of SCA in people with diabetes mellitus and this paradoxical association should be recognized and extended to clinical preventive measures.

Being Underweight Is Associated with Increased Risk of Sudden Cardiac Death in People with Diabetes Mellitus

BACKGROUND

Diabetes mellitus (DM) can cause various atherosclerotic cardiovascular disease including sudden cardiac death (SCD). The impact of being underweight on the risk of SCD in people with DM remains to be revealed. We aimed to evaluate the risk of SCD according to body-mass index (BMI; kg/m²) level in DM population.

METHODS

We used a nationwide healthcare insurance database to conduct this study. We identified people with DM among those who underwent nationwide health screening during 2009 to 2012. Medical follow-up data was available until December 2018.

RESULTS

A total of 2,602,577 people with DM with a 17,851,797 person*year follow-up were analyzed. The underweight group (BMI < 18.5) showed 2.4-fold increased risk of SCD during follow-up (adjusted-hazard ratio [HR] = 2.40; 95% confidence interval [CI] = 2.26-2.56; p < 0.001). When normal-BMI group (18.5 ≤ BMI < 23) was set as a reference, underweight group (adjusted-HR = 2.01; 95% CI = 1.88-2.14) showed even higher risk of SCD compared with the obesity group (BMI ≥ 30; adjusted-HR = 0.89; 95% CI = 0.84-0.94). When BMI was stratified by one unit, BMI and SCD risk showed a U-curve association with the highest risk observed at low BMI levels. The lowest risk was observed in 27 ≤ BMI < 28 group. The association between being underweight and increased SCD risk in DM people was maintained throughout various subgroups.

CONCLUSIONS

Being underweight is significantly associated with an increased risk of SCD in the DM population. A steep rise in the risk of SCD was observed as the BMI level decreased below 23. The lowest risk of SCD was observed in 27 ≤ BMI < 28 group.

Sarcopenia assessed with DXA and CT increases the risk of perioperative complications in patients with gastrectomy

OBJECTIVES

We investigated sarcopenia prevalence using various diagnostic criteria based on dual-energy X-ray absorptiometry (DXA) and computed tomography (CT) in gastric cancer patients who underwent gastrectomy, and evaluated the association between sarcopenia and perioperative complications.

METHODS

This retrospective study included consecutive patients with gastric cancer who underwent gastrectomy, and preoperative DXA and CT from January 2013 to November 2020. Body composition was measured using DXA and CT. Height-adjusted DXA-based Appendicular Skeletal Muscle Mass Index (ASMI) and CT-based skeletal muscle cross-sectional area at the L3 level (SMI) were measured. Sarcopenia and sarcopenic obesity were defined using reported cutoff values. The chi-square test and univariate analysis were performed to determine risk factors for significant and severe perioperative complications (Clavien-Dindo Grades ≥ 2 and ≥ 3, respectively).

RESULTS

In total, 77 males and 43 females aged 61.4 ± 11.0 years were included. ASMI and SMI were correlated (r = 0.819), but sarcopenia prevalence varied (20.0-63.3%), depending on the criteria applied. Univariate analysis revealed sarcopenia defined using the Asian Working Group on Sarcopenia (AWGS) criteria and sarcopenic obesity as risk factors for significant (odds ratio [OR] 2.76, p = 0.030 vs. OR 4.31, p = 0.002) and severe perioperative complications (OR 3.77, p = 0.036 vs. OR 4.78, p = 0.010). In subgroup analyses, sarcopenia and sarcopenic obesity were significantly associated with perioperative complications only in males.

CONCLUSION

Perioperative complication risk can be predicted from sarcopenia defined using the AWGS criteria and sarcopenic obesity measured using DXA and CT, particularly in males.

KEY POINTS

• The prevalence of sarcopenia varies due to definition differences. • Sarcopenia and sarcopenic obesity are risk factors for significant and severe perioperative complications, particularly in males. • Our results suggest that physicians need to pay attention to perioperative complications after surgical treatment of male patients with sarcopenia and sarcopenic obesity.

Diagnostic usefulness of implantable loop recorder in patients with unexplained syncope or palpitation

Background

In a substantial proportion of patients with syncope, the exact cause is not identified because of the difficulty to document electrocardiograms correlated with the events during a syncope episode. Thus, an implantable loop recorder (ILR) was introduced for diagnosing hidden arrhythmia; however, its clinical use remains limited. Therefore, we conducted a retrospective analysis to assess the diagnostic value of the ILR in patients with unexplained syncope or palpitations.

Methods

All patients who had undergone ILR implantation from May 2016 to January 2020, were studied retrospectively. We analyzed their electrocardiogram stored in the device.

Results

Among the 70 patients (mean age ± SD; 50.2 ± 20.3 years, 27 men) with unknown causes of syncope or palpitation, during two years follow-up, arrhythmia was detected in 26 patients (37.1%). Nineteen (73.1%) patients underwent permanent pacemaker implantation due to symptomatic bradycardia or atrioventricular block. All arrhythmias were detected within 6 days to 39 months after loop recorder implantation. Thirteen patients (50%) showed sick sinus syndrome (eight long pauses and five tachycardia-bradycardia syndromes). Eleven patients (42.3%) had paroxysmal atrioventricular block. Two patients who underwent permanent pacemaker implantation showed a positive tilt-table test. Three patients underwent radiofrequency catheter ablation for paroxysmal supraventricular tachycardia and atrial fibrillation. The mean duration for the detection of first sign (arrhythmia or palpitations) was 7.5 months, and the time from the detection of arrhythmia to ablation or device implantation was 3.4 months.

Conclusion

ILR monitoring detected a substantial number of significant bradycardias in patients with unexplained syncope and palpitations, suggesting that it is an effective diagnostic method that can shorten the time required to identify the cause of arrhythmias.

Simple fabrication of an electrospun polystyrene microfiber filter that meets N95 filtering facepiece respirator filtration and breathability standards

During the global spread of COVID-19, high demand and limited availability of melt-blown filtration material led to a manufacturing backlog of N95 Filtering Facepiece Respirators (FFRs). This shortfall prompted the search for alternative filter materials that could be quickly mass produced while meeting N95 FFR filtration and breathability performance standards. Here, an unsupported, nonwoven layer of uncharged polystyrene (PS) microfibers was produced via electrospinning that achieves N95 performance standards based on physical parameters (e.g., filter thickness) alone. PS microfibers 3-6 μm in diameter and deposited in an ~5 mm thick filter layer are favorable for use in FFRs, achieving high filtration efficiencies (≥97.5%) and low pressure drops (≤15 mm H₂O). The PS microfiber filter demonstrates durability upon disinfection with hydroxyl radicals (•OH), maintaining high filtration efficiencies and low pressure drops over six rounds of disinfection. Additionally, the PS microfibers exhibit antibacterial activity (1-log removal of E. coli) and can be modified readily through integration of silver nanoparticles (AgNPs) during electrospinning to enhance their activity (≥3-log removal at 25 wt% AgNP integration). Because of their tunable performance, potential reusability with disinfection, and antimicrobial properties, these electrospun PS microfibers may represent a suitable, alternative filter material for use in N95 FFRs.

Flocculation kinetics and mechanisms of microalgae- and clay-containing suspensions in different microalgal growth phases

Interplays between microalgae and clay minerals enhance biologically mediated flocculation, thereby affecting the sedimentation and transportation of suspended particulate matter (SPM) in water and benthic environments. This interaction forms larger flocs with a higher settling velocity and enhances SPM sinking. The aim of this study was to investigate the flocculation kinetics of microalgae and clay in suspension and to elucidate the mechanisms associated with such interactions. Standard jar test experiments were conducted using various mixtures of kaolinite and microalgal samples from batch cultures (Chlorella vulgaris) to estimate biologically mediated flocculation kinetics. The organic matter (OM) composition secreted by the microalgae was characterized using a liquid chromatography - organic carbon detection system, and quantitative analysis of transparent exopolymer particles was conducted separately. A two-class flocculation kinetic model, based on the interaction between flocculi and flocs, was also adopted to quantitatively analyze the experimental data from flocculation. Results from the flocculation kinetic tests and OM analyses, in association with other data analyses (i.e., floc size distribution and flocculation kinetic model), showed that flocculation increased with OM concentration during the growth phase (10-20 d). However, on day 23 during the early stationary phase, flocculation kinetics started decreasing and substantially declined on day 30, even though the amount of OM (mainly biopolymers) continued to increase. Our results indicate that an adequate quantity of biopolymers produced by the microalgal cells in the growth phase enhanced floc-to-floc attachment and hence flocculation kinetics. In contrast, an excessive quantity of biopolymers and humic substances in the stationary phase enhanced the formation of polymeric backbone structures and flocculation via scavenging particles but simultaneously increased steric stabilization with the production of a large number of fragmented particles.

Late ventricular potential for risk prediction of sudden cardiac death risk: a valuable tool or an unnecessary step?

Background/Introduction

Signal-averaged electrocardiography (SA-ECG) is a high-resolution electrocardiography that can detect late ventricular potential, which known to be a noninvasive tool for risk stratification of sudden cardiac death (SCD) by predicting reentrant ventricular tachyarrhythmia. There is a paucity of data with SA-ECG on SCD survivors without structural heart disease, whereas majority of previous studies had been focused on post myocardial infarction survivors.

Purpose

This study assessed the clinical utility of SA-ECG as a risk stratification modality for lethal arrhythmic event in patients at risk of SCD without definite structural heart disease.

Methods

Total 629 patients who experienced or had potential risk of SCD were studied with SA-ECG. Among them, 48 patients who were found to have significant structural heart disease were excluded, except arrhythmogenic right ventricular cardiomyopathy. Major arrhythmic event (MAE) was defined as composite of all-cause death, aborted SCD, and sustained VT during any time either before visit of clinic or during follow up period. Syncope and non-sustained VT was defined as non-major arrhythmic event. SA-ECG was defined positive when fulfilling three or more criterion: (1) unfiltered QRS duration ≥114ms, (2) filtered QRS duration ≥114ms, (3) duration of terminal QRS &lt;40uV exceeding 40ms, and (4) root mean square voltage in the terminal 40ms of ≤20ms.

Results

Among total 581 patients, 145 patients with positive SA-ECG showed higher incidence of MAE compared to patients with negative SA-ECG (21.4% vs. 6.7%, OR 3.816 [95% CI 2.208–6.597], p&lt;0.001, Table). As the number of positive SA-ECG criteria increases, incidence of MAE tended to increase sequentially, which was markedly noted from 2 positive to 3 positive criteria (10.7% to 20.8%, p&lt;0.001, Figure). In particular, patient with inherited arrhythmia showed higher rate of positive late potential compared to those with non-inherited arrhythmia (51.0% vs. 19.3%, p&lt;0.001).

Conclusion

This study showed that at least 3 out of 4 diagnostic criteria in SA-ECG can independently predict lethal arrhythmic events and the positive late potential was associated with lethal arrhythmic event that leads to SCD, suggesting risk prediction for SCD using SA-ECG in patients even without structural heart disease including inherited arrhythmias.

Funding Acknowledgement

Type of funding sources: None.

Clinical role of genetic testing for overlapping between Brugada syndrome and arrhythmogenic right ventricular cardiomyopathy

Background/Introduction

Brugada syndrome (BrS) and arrhythmogenic right ventricular cardiomyopathy (ARVC) are inherited arrhythmias that may predispose to sudden cardiac arrest. Although its pathogenetic mechanisms differ, overlapping features between BrS and ARVC have been demonstrated previously. However, it remains to be determined whether genetic testing for ARVC-related gene is needed in patients with BrS.

Purpose

This study is aimed to analyze genetic profiles of BrS patients using next generation sequencing (NGS) based multigene panel including ARVC related genes.

Methods

Patients who were confirmed as BrS or clinically suspected as BrS with type 2 or 3 Brugada pattern electrocardiography were studied. Genetic testing using NGS panels (Illumina Inc., San Diego, CA, USA) included 30 genetic variants associated with inherited arrhythmia and genetic cardiomyopathy.

Results

Among the total 119 patients from BrS registry, 63 patients were confirmed as BrS and 56 patients were clinically suspected as BrS without fulfilling diagnostic criteria. One-hundred-fourteen patients (95.8%) were male, and mean age of onset was 43.6 year-old. Genetic variants were identified in 25 of 42 patients who received genetic testing. Six out of 25 patients (24.0%) showed ARVC-related genotypes (2 PKP2, 1 DSG2, 1 TMEM43, 1 JUP, and 1 DSP) (Figure 1 and Table 1). None of the patients showed structural or electrocardiographic features that fulfill diagnostic criteria of ARVC. It is notable that ARVC-related genotypes were mostly frequently accounted for BrS patients, following SCN5A and SCN10A.

Conclusion

In the clinic setting, ARVC-related genetic variants were identified in significant proportion of BrS patients, supporting that genetic testing of ARVC-overlapping is needed. This study suggests that follow-up including imaging study should be considered in BrS patients with ARVC-related genotypes to monitor disease progression as ARVC.

Funding Acknowledgement

Type of funding sources: None.

Correlations Between Coronary Artery Disease, Coronary Artery Calcium Score, and Lipoprotein(a) Level in Korea

Background

Methods

Results

Conclusion

Sex-Related Differences in Left Atrial Low-Voltage Areas According to CHA2DS2-VA Scores among Patients with Atrial Fibrillation

(1) Background: We hypothesized that female sex would have a differential impact on left atrial (LA) low-voltage areas (LVAs) according to CHA2DS2-VA scores. (2) Methods: This study included 553 patients who underwent radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF). LVAs were defined as regions with bipolar peak-to-peak voltages of <0.5 mV. The proportion of LVAs was calculated by dividing the total LVA by the LA surface area. (3) Results: There was no sex-related difference in LA LVAs among patients with a CHA2DS2-VA scores ≤ 2. The proportion of LVAs was significantly higher in females among patients with CHA2DS2-VA scores of 3 or 4 (10.1 (4.7−15.1)% vs. 15.8 (9.2−32.1)%; p = 0.027). Female sex was significantly associated with extensive LVAs (LVA proportion ≥ 30%). Females had odd ratios of 27.82 (95% confidence interval (CI) 3.33−756.8, p = 0.01), and 1.53 (95% CI 0.81−2.83, p = 0.184) for extensive LAVs in patients with CHA2DS2-VA scores ≥ 3 and CHA2DS2-VA scores < 3, respectively. In the multiple regression model, female patients with a CHA2DS2-VA ≥3 were significantly associated with a higher proportion of LVAs (β = 8.52, p = 0.039). (4) Conclusions: Female sex was significantly associated with extensive LVAs, particularly when their CHA2DS2-VA scores were ≥3. This result suggests that female sex has a differential effect on the extent of LVAs based on the presence of additional risk factors.

Metabolic Syndrome, Gamma-Glutamyl Transferase, and Risk of Sudden Cardiac Death

Background: Metabolic syndrome is associated with a significantly increased risk of sudden cardiac death (SCD). However, whether temporal changes in the metabolic syndrome status are associated with SCD is unknown. We aimed to determine whether metabolic syndrome and gamma-glutamyl transferase (ɣ-GTP), including their temporal changes, are associated with the risk of SCD. Methods: We performed a nationwide population-based analysis using the Korean National Health Insurance Service. People who underwent a national health check-up in 2009 and 2011 were enrolled. The influence of metabolic syndrome and ɣ-GTP on SCD risk was evaluated. Results: In 2009, 4,056,423 (848,498 with metabolic syndrome) people underwent health screenings, 2,706,788 of whom underwent follow-up health screenings in 2011. Metabolic syndrome was associated with a 50.7% increased SCD risk (adjusted hazard ratio (aHR) = 1.507; p < 0.001). The SCD risk increased linearly as the metabolic syndrome diagnostic criteria increased. The ɣ-GTP significantly impacted the SCD risk; the highest quartile had a 51.9% increased risk versus the lowest quartile (aHR = 1.519; p < 0.001). A temporal change in the metabolic syndrome status and ɣ-GTP between 2009 and 2011 was significantly correlated with the SCD risk. Having metabolic syndrome in 2009 or 2011 indicated a lower SCD risk than having metabolic syndrome in 2009 and 2011 but a higher risk than having no metabolic syndrome. People with a ≥20-unit increase in ɣ-GTP between 2009 and 2011 had an 81.0% increased SCD risk versus those with a change ≤5 units (aHR = 1.810; p < 0.001). Conclusions: Metabolic syndrome and ɣ-GTP significantly correlated with an increased SCD risk. SCD was also influenced by temporal changes in the metabolic syndrome status and ɣ-GTP, suggesting that appropriate medical treatment and lifestyle modifications may reduce future SCD risk.

Association of Depression With Atrial Fibrillation in South Korean Adults

IMPORTANCE

The risk of atrial fibrillation (AF) in people with depression is not fully known. Depression is associated with sympathetic activation and emotional stress, which might increase the risk of new-onset AF.

OBJECTIVE

To assess the incidence of new-onset AF in those with and without depression using data from a nationwide health care database.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study obtained data from the Korean National Health Insurance Service database and enrolled people who underwent a nationwide health checkup in 2009. People younger than 20 years and those with a history of heart valve surgery, previous diagnosis of mitral stenosis, or who were diagnosed with AF between January 1, 2002 and December 31, 2008 were excluded. The risk of new-onset AF (occurring between 2009 and 2018) was compared in people who were and were not diagnosed with depression within a year before the 2009 nationwide health checkup. Data were analyzed between August 1, 2020 and October 31, 2020.

EXPOSURE

Previous diagnosis of depression.

MAIN OUTCOMES AND MEASURES

Cumulative incidence and risk of new-onset AF between 2009 and 2018 in participants with and without depression. Kaplan-Meier analysis was conducted to assess incidence of AF, and Cox proportional hazards regression was used to calculate adjusted and unadjusted hazard ratios (HRs) and 95% CIs.

RESULTS

A total of 5 031 222 individuals with a mean (SD) age of 46.99 (14.06) years (2 771 785 men [55.1%]) were included in the analysis; of these individuals, 148 882 (3.0%) had a diagnosis of depression in the year before the 2009 health checkup and 4 882 340 (97%) did not. People with depression vs those without depression were older (aged 56.7 vs 46.7 years) and more likely to be women (96 472 [64.8%] vs 2 162 965 [44.3%]). Prevalence of hypertension, diabetes, dyslipidemia, and heart failure was higher in the depression group. The cumulative incidence of new-onset AF was significantly higher in people with depression vs without depression in the Kaplan-Meier analysis and showed steady divergence throughout 10 years of follow-up (cumulative incidence, 4.44% vs 1.92%; log-rank P < .001). After adjusting for covariates, depression was associated with a 25.1% increased risk of new-onset AF (HR, 1.25; 95% CI, 1.22-1.29; P < .001). People with recurrent episodes of depression showed even higher risk of new-onset AF (HR, 1.32; 95% CI, 1.27-1.37; P < .001). Young age and female sex had significant interactions with depression, which suggests that young people and women with depression may have an increased risk of new-onset AF.

CONCLUSIONS AND RELEVANCE

This study found that depression was associated with a significantly increased cumulative incidence and risk of new-onset AF. Recurrent episodes of depression were associated with even higher risk. These findings suggest the need for adequate screening for AF in people with depression, particularly in younger people and women.

Electrical Remodeling of Left Atrium Is a Better Predictor for Recurrence Than Structural Remodeling in Atrial Fibrillation Patients Undergoing Radiofrequency Catheter Ablation

We demonstrated that the electrical remodeling represented by low voltage zone is a better marker for the prediction of recurrence after radiofrequency catheter ablation as compared with structural remodeling measured by left atrium (LA) diameter. The study provides important clue that further deep dive into LA substrate research will be important to improve success rate of non-paroxysmal atrial fibrillation ablation.

Background and Objectives

Recurrence rates after radiofrequency catheter ablation (RFCA) in atrial fibrillation (AF) patients are not low especially in non-paroxysmal AF. The diameter of left atrium (LA) has been widely used to predict the recurrence after RFCA for decades. However, LA diameter represents structural remodeling of LA and does not reflect electrical remodeling. We aimed to determine the predictive value of electrical remodeling of LA which is represented by the amount of low voltage zone (LVZ).

Methods

We performed a retrospective cohort analysis of AF patients who underwent de novo RFCA in a single-center.

Results

A total of 3,120 AF patients with de novo RFCA were analyzed. Among these patients, 537 patients underwent an electroanatomic mapping with bipolar voltage measurement of LA. The diameter of LA and flow velocity of LA appendage (LAA) differed significantly according to quartile group of LVZ area and percentage: patients with high LVZ had large LA diameter and low LAA flow velocity (p<0.001). Freedom from late recurrence (LR) was significantly lower in patients with high LVZ area and percentage (p<0.001). The diameter and surface area of LA had area under curve (AUC) of 0.592 and 0.593, respectively (p=0.002 for both). The predictive value of LVZ area (AUC, 0.676) and percentage (AUC, 0.671) were both superior compared with LA diameter (p=0.011 and 0.027 for each comparison).

Conclusions

In conclusion, LVZ can predict freedom from LR after RFCA in AF patients. Predictive value was higher in parameters reflecting electrical rather than structural remodeling of LA.

Changes in treatment intent and target definition for preoperative radiotherapy after 18F-Fluorodeoxyglucose positron emission tomography in rectal cancer: A Meta-analysis

PURPOSE

To evaluate the impact of ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography (PET) on changes in treatment plan and target definition for preoperative radiotherapy in patients with rectal cancer.

METHODS

Embase, PubMed, and Cochrane Library were searched up to November 2020 for all studies investigating the role of preoperative FDG PET in patients who underwent neoadjuvant radiotherapy before curative-intent surgery. The proportion of patients whose treatment plan (curative vs. palliative intent) or target definition was changed after FDG PET was analyzed. A random-effects model was used for pooled analysis. The change in target definition was compared between conventional radiological imaging-based target volume [gross tumor volume (GTV) or planning target volume (PTV)] and PET-based target volume (GTV or PTV) using the standardized mean difference (SMD) and 95% confidence interval (CI).

RESULTS

A total of 336 patients from twelve studies were included. In eight studies, PET changed either the treatment intent or target definition in 24.8% of patients (95% CI 15.1% to 37.9%, I² = 69%). In ten studies, the PET-based GTV was lower than the conventional imaging-based target volume (SMD -7.0, 95% CI -1.39 to -0.01). However, there was no significant difference between conventional imaging-based and PET-based PTV (SMD -0.07, 95% CI -0.75 to 0.62). In six studies evaluating the initial staging based on PET, the initial staging (nodal or metastasis status) was changed in 53 of 229 patients (23.1%). Newly detected or additional distant metastases were identified in 22 patients (9.6%) after FDG PET.

CONCLUSION

The use of FDG PET influences radiotherapy planning in a fourth of patients with rectal cancer. FDG PET can provide additive information for accurate tumor delineation, although PET-based PTV did not significantly change. These findings suggest that FDG PET may be beneficial to patients with rectal cancer before establishing a radiotherapy plan.

Dynamic Pore Modulation of Stretchable Electrospun Nanofiber Filter for Adaptive Machine Learned Respiratory Protection

The recent emergence of highly contagious respiratory disease and the underlying issues of worldwide air pollution jointly heighten the importance of the personal respirator. However, the incongruence between the dynamic environment and nonadaptive respirators imposes physiological and psychological adverse effects, which hinder the public dissemination of respirators. To address this issue, we introduce adaptive respiratory protection based on a dynamic air filter (DAF) driven by machine learning (ML) algorithms. The stretchable elastomer fiber membrane of the DAF affords immediate adjustment of filtration characteristics through active rescaling of the micropores by simple pneumatic control, enabling seamless and constructive transition of filtration characteristics. The resultant DAF-respirator (DAF-R), made possible by ML algorithms, successfully demonstrates real-time predictive adapting maneuvers, enabling personalizable and continuously optimized respiratory protection under changing circumstances.

The usefulness of trabecular bone score in patients with ankylosing spondylitis

BACKGROUNDS/AIMS

This study was performed to reveal the usefulness of the trabecular bone score (TBS) in assessing bone strength in patients with ankylosing spondylitis (AS) in comparison with dual-energy X-ray absorptiometry (DXA) methods.

METHODS

A total of 215 AS patients (75.8% male) were enrolled from a single university hospital in Korea. Demographic and clinical information were assessed. Patients completed X-rays of the cervical and lumbar spine (L-spine), and spinal ankyloses were quantified using the modified Stoke AS Spine Score (mSASSS). Hip, anteroposterior and lateral L-spine bone mineral density (BMD) and TBS were assessed by DXA methods. Clinical characteristics and bone strength measurement results were compared between male and female AS patients. The accuracy of each bone strength evaluation method in predicting Fracture Risk Assessment Tool (FRAX) scores indicating moderate or higher fracture risk was compared by receiver operating characteristic curves in patients aged ≥ 40 years. Correlations between each bone strength measurement method and mSASSS were examined.

RESULTS

Male patients showed higher mSASSS and less prevalent peripheral joint involvement compared to female patients (p < 0.05). TBS, hip BMD, and L-spine lateral BMD showed comparably high areas under the curve (AUCs) for predicting FRAX-major osteoporotic fractures (MOF) ≥ 10% (AUC ranged 0.72 to 0.76). TBS negatively correlated with mSASSS in both male and female patients (p < 0.01).

CONCLUSION

TBS could predict the risk of MOF and is not influenced by spinal osteoproliferation in AS patients, even in those with advanced spinal changes.

Intrasubject relationship between striatal 18F-FP-CIT uptake and cardiac 123I-MIBG uptake differs by motor subtype in early Parkinson disease

Parkinson disease (PD) is a heterogeneous neurodegenerative disorder. Dopamine transporter imaging using 123I-2β-carbomethoxy-3β-(4-iodophenyl)-N-(3-fluoropropyl)-nortropane (FP-CIT) and noradrenergic cardiac imaging using 123I-meta-iodobenzylguanidine (MIBG) have been used in combination or separately to study PD patients. Published results regarding uptake of the 2 tracers in each motor subtype are fairly abundant and mostly in agreement. However, data on the intrasubject association between dopaminergic and noradrenergic systems in PD patients are relatively scant and vary. We aimed to assess the intrasubject relationship between striatal dopamine transporter density using a PET tracer and cardiac sympathetic innervation in tremor-dominant subtype (TD) and akinetic-rigid subtype (AR) of PD.This study has a cross-sectional design. Thirty-one patients with early PD (17 TD/14 AR) who underwent both 123I-MIBG cardiac scintigraphy and 18F-FP-CIT PET/CT were retrospectively selected. We assessed the relationship between heart-to-mediastinum ratio (H/M) of 123I-MIBG and specific (striatal)-to-nonspecific (cerebellar) dopamine transporter binding ratio (S/N) measured from 4 separate regions-of-interest (bilateral caudate nuclei and lentiform nuclei) of 18F-FP-CIT in each motor subtype.S/N of all 4 striatal regions were significantly lower in the AR subgroup than in the TD subgroup. H/M was not significantly different. There was a significant intrasubject correlation between H/M and S/N of the lentiform nucleus in AR-PD but no correlation between H/M and any of 4 S/N in TD-PD.Our data suggest a coupled degeneration of nigrostriatal dopaminergic and myocardial sympathetic denervation in AR subtype, but not in TD subtype, of early PD patients. These different results between the 2 motor subtypes likely reflects the heterogeneous pathophysiology of PD.

CT texture analysis of tonsil cancer: Discrimination from normal palatine tonsils

The purposes of the study were to determine whether there are differences in texture analysis parameters between tonsil cancers and normal tonsils, and to correlate texture analysis with 18F-FDG PET/CT to investigate the relationship between texture analysis and metabolic parameters. Sixty-four patients with squamous cell carcinoma of the palatine tonsil were included. A ROI was drawn, including all slices, to involve the entire tumor. The contralateral normal tonsil was used for comparison with the tumors. Texture analysis parameters, mean, standard deviation (SD), entropy, mean positive pixels, skewness, and kurtosis were obtained using commercially available software. Parameters were compared between the tumor and the normal palatine tonsils. Comparisons were also performed among early tonsil cancer, advanced tonsil cancer, and normal tonsils. An ROC curve analysis was performed to assess discrimination of tumor from normal tonsils. Correlation between texture analysis and 18F-FDG PET/CT was performed. Compared to normal tonsils, the tumors showed a significantly lower mean, higher SD, higher entropy, lower skewness, and higher kurtosis on most filters (p<0.001). On comparisons among normal tonsils, early cancers, and advanced tonsil cancers, SD and entropy showed significantly higher values on all filters (p<0.001) between early cancers and normal tonsils. The AUC from the ROC analysis was 0.91, obtained from the entropy. A mild correlation was shown between texture parameters and metabolic parameters. The texture analysis parameters, especially entropy, showed significant differences in contrast-enhanced CT results between tumor and normal tonsils, and between early tonsil cancers and normal tonsils. Texture analysis can be useful as an adjunctive tool for the diagnosis of tonsil cancers.

Effectiveness of bazedoxifene in preventing glucocorticoid-induced bone loss in rheumatoid arthritis patients

Objective

To evaluate the effectiveness of bazedoxifene in preventing bone loss in patients with rheumatoid arthritis (RA) receiving low-dose glucocorticoids (GCs).

Methods

In this randomized, controlled, open-label study, we assigned postmenopausal women with osteopenia who had been receiving low-dose GCs for RA to two groups: a group receiving bazedoxifene (20 mg/day) with elemental calcium 1200 mg and vitamin D 800 IU daily (bazedoxifene group) and a group receiving the same doses of calcium and vitamin D only (control group). As primary outcome, bone mineral density (BMD) change in the lumbar spine (L-spine) from baseline to 48 weeks was assessed. Changes in BMD in the femur, trabecular bone score, bone turnover markers, and development of fracture were assessed as secondary outcomes. For intention-to-treat analysis, 20 completed data sets were created by applying multiple imputations by chained equations.

Results

A total of 114 patients (57 patients in each group) were recruited. A significant increase in L-spine BMD (0.015 g/cm², P = 0.007) was observed in the bazedoxifene group, and the increase was significantly higher than in the control group (0.013, 95% CI 0.0003–0.026, P = 0.047). Reductions in bone turnover markers in the bazedoxifene group were significantly greater than in the control group. Only one fracture was observed in the bazedoxifene group, while four fractures developed in the control group.

Conclusion

In postmenopausal patients with RA receiving low-dose GCs, bazedoxifene improved BMD and reduced bone turnover markers. However, the change in BMD did not exceed the least significant change.

Trial registration

ClinicalTrials.gov, NCT02602704.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-021-02564-1.

Adverse effects of adjuvant tamoxifen treatment on bone mineral density in premenopausal breast cancer patients: A systematic review and meta-analysis

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Background: It is well known that adjuvant tamoxifen treatment for breast cancer in postmenopausal women decreases bone loss. However, the adverse effect of adjuvant tamoxifen therapy for bone mineral density (BMD) in premenopausal breast cancer patients remains uncertain. This meta-analysis aimed to assess the effects of adjuvant tamoxifen therapy on BMD changes in premenopausal women with primary breast cancer. Methods: Through April 2020, studies reporting BMD changes of lumbar spine or hip in premenopausal women with primary breast cancer treated with adjuvant tamoxifen were collected from EMBASE and PubMed. The pooled analysis was performed using random effects model of the standardized mean difference (SMD) of BMD in patients. Results: A total of 1,432 premenopausal patients from eight studies were included in the pooled analysis. After 3 years of median follow up, adjuvant tamoxifen therapy decreased BMD by as much as SMD of -0.79 [95% confidence interval (CI); -1.25 to -0.33, P < 0.01] at lumbar spines and -0.38 at hip (95%CI; -0.88 to 0.12, P > 0.05). Compared with patients received tamoxifen alone, patients who received combination therapy with chemotherapy or ovarian function suppression (OFS) showed decreased bone loss at lumbar spine (SMD -1.17 with 95%CI -1.59 to -0.75, -0.43 with 95%CI -2.26 to 1.40, and -0.75 with 95%CI -1.38 to -0.13, respectively). Conclusions: Our meta-analysis revealed that premenopausal women who received adjuvant tamoxifen treatment showed significant bone loss over a period of time, especially at lumbar spine. However, tamoxifen attenuated bone loss in those who received tamoxifen after chemotherapy or along with OFS.[Table: see text]

Paediatric sudden unexpected death in epilepsy: A parental report cohort

BACKGROUND

Sudden unexpected death in epilepsy (SUDEP) accounts for a large percentage of deaths in children with epilepsy. Contributing factors to paediatric SUDEP are incompletely understood.

AIMS OF STUDY

The Epilepsy Deaths Register (EDR) is an anonymized register that compiles information on deaths related to epilepsy, across all ages and epilepsy classifications. Using the EDR, we sought to identify key risk factors for SUDEP in children to assist the development of preventive measures.

METHODS

All registrations between the ages of 1 and 16 years were reviewed to identify definite or probable SUDEP. These cases were analysed to identify common demographics, comorbidities, monitoring, treatments and circumstances near to the deaths.

RESULTS

We identified forty-six cases (27 males) of definite or probable SUDEP. Paediatric SUDEP is more common in a 12- to 16-year age group and in those with neuro-disability. Most paediatric SUDEP occurs during apparent sleep. There were four cases with a vagus nerve stimulator. SUDEP can occur early after the onset of seizures.

CONCLUSIONS

This is the largest single cohort of SUDEP reported in children. Reports from caregivers can augment population data. Surveillance in sleep is a priority area of development.

Analysis of avoidable cardiopulmonary resuscitation incidents with a part-time rapid response system in place

Background:

Although a rapid response system (RRS) can reduce the incidence of cardiopulmonary resuscitation (CPR) in general wards, avoidable CPR cases still occur. This study aimed to investigate the incidence and causes of avoidable CPR.

Methods:

We retrospectively reviewed the medical records of all adult patients who received CPR between April 2013 and March 2016 (35 months) at a tertiary teaching hospital where a part-time RRS was introduced in October 2012. Four experts reviewed all of the CPR cases and determined whether each event was avoidable.

Results:

A total of 192 CPR cases were identified, and the incidence of CPR was 0.190 per 1,000 patient admissions. Of these, 56 (29.2%) were considered potentially avoidable, with the most common cause being doctor error (n=32, 57.1%), followed by delayed do-not-resuscitate (DNR) placement (n=12, 21.4%) and procedural complications (n=5, 8.9%). The percentage of avoidable CPR was significantly lower in the RRS operating time group than in the RRS non-operating time group (20.7% vs. 35.5%; P=0.026). Among 44 avoidable CPR events (excluding cases related to DNR issues), the rapid response team intervened in only three cases (6.8%), and most of the avoidable CPR cases (65.9%) occurred during the non-operating time.

Conclusions:

A significant number of avoidable CPR events occurred with a well-functioning, part-time RRS in place. However, RRS operation does appear to lower the occurrence of avoidable CPR. Thus, it is necessary to extend RRS operation time and modify RRS activation criteria. Moreover, policy and cultural changes are needed prior to implementing a full-time RRS.

Effects of Wearable Powered Exoskeletal Training on Functional Mobility, Physiological Health and Quality of Life in Non-ambulatory Spinal Cord Injury Patients

BACKGROUND

Spinal cord injury (SCI) is a serious clinical condition that impacts a patient's physical, psychological, and socio-economic status. The aim of this pilot study was to evaluate the effects of training with a newly developed powered wearable exoskeleton (Hyundai Medical Exoskeleton [H-MEX]) on functional mobility, physiological health, and quality of life in non-ambulatory SCI patients.

METHODS

Participants received 60 minutes of walking training with a powered exoskeleton 3 times per week for 10 weeks (total 30 sessions). The 6-minute walking test (6MWT) and timed-up-and-go test (TUGT) were performed to assess ambulatory function. The physiological outcomes of interest after exoskeleton-assisted walking training were spasticity, pulmonary function, bone mineral density, colon transit time, and serum inflammatory markers. Effects of walking training on subjective outcomes were estimated by the Korean version of the Falls Efficacy Scale-International and the 36-Item Short-Form Health Survey version 2.

RESULTS

Ten participants finished 30 sessions of training and could ambulate independently. No severe adverse events were reported during the study. After training, the mean distance walked in the 6MWT (49.13 m) was significantly enhanced compared with baseline (20.65 m). The results of the TUGT also indicated a statistically significant improvement in the times required to stand up, walk 3 m and sit down. Although not statistically significant, clinically meaningful changes in some secondary physiological outcomes and/or quality of life were reported in some participants.

CONCLUSION

In conclusion, this study demonstrated that the newly developed wearable exoskeleton, H-MEX is safe and feasible for non-ambulatory SCI patients, and may have potential to improve quality of life of patients by assisting bipedal ambulation. These results suggest that the H-MEX can be considered a beneficial device for chronic non-ambulatory SCI patients.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04055610.

Different Influence of Blood Pressure on New-Onset Atrial Fibrillation in Pre- and Postmenopausal Women: A Nationwide Population-Based Study

[Figure: see text].

Early Recurrence Is Reliable Predictor of Late Recurrence After Radiofrequency Catheter Ablation of Atrial Fibrillation

OBJECTIVES

This study aimed to compare the risk of late recurrence in patients with and without early recurrence.

BACKGROUND

Early recurrence of atrial fibrillation (AF) or atrial tachycardia (AT) after radiofrequency catheter ablation (RFCA) in AF patients is known to be a transient phenomenon. The theoretical basis of the blanking period is based on such observations. However, the clinical implications of early recurrence need further validation.

METHODS

Consecutive RFCA cases in a tertiary hospital were analyzed. Early recurrence was defined as any AT or AF event occurring within 90-days post-RFCA. Early recurrence as AT and AF were also analyzed separately.

RESULTS

A total of 3,120 patients underwent RFCA. Early recurrence occurred in 751 patients (24.1%). Patients who experienced early recurrence had a larger left atrium, worse hemodynamics in the left atrial appendage, and a higher prevalence of nonparoxysmal AF and heart failure. Among patients who experienced early recurrence, 69.6% of patients eventually had late recurrence. Early recurrence was associated with a 4.3- and 3.6-fold increase in the risk of late recurrence after single and multiple procedures, respectively. After multivariate adjustment, early recurrence was an independent risk factor for late recurrence with 3.6- and 2.8-fold increase in the risk of late recurrence after single and multiple procedures, respectively. Early recurrence AT had a lower risk of late recurrence compared with early recurrence AF.

CONCLUSIONS

Early recurrence was a reliable predictor for late recurrence. The clinical significance of the blanking period in the current guidelines may need to be revisited.

Blood flow volume of left atrial appendage measured by magnetic resonance imaging is improved after radiofrequency catheter ablation of atrial fibrillation

INTRODUCTION

Hemodynamics of left atrial appendage (LAA) is an important factor for future risk of ischemic stroke in atrial fibrillation (AF) patients. Velocity encoded cardiac magnetic resonance imaging (VENC-MRI) can evaluate blood flow volume of LAA without any invasive procedures. We aimed to evaluate the association between radiofrequency catheter ablation (RFCA) and LAA hemodynamics measured by MRI.

METHODS AND RESULTS

Consecutive RFCA cases in a single arrhythmia center were retrospectively analyzed. A total of 3120 AF patients who underwent first RFCA were analyzed. Among these patients 360 patients had both pre- and post-RFCA VENC-MRI evaluation. Atrial fibrillation was non-paroxysmal in 174 (48.3%) patients. Mean VENC-MRI (ml/sec) was significantly improved after RFCA with 49.93 ± 32.92 and 72.00 ± 34.82 for pre- and post-RFCA, respectively. Patients with non-paroxysmal AF (∆VENC-MRI = 14.63 ± 40.67 vs. 30.03 ± 35.37; p < .001) and low pre-RFCA VENC-MRI (∆VENC-MRI = 17.19 ± 38.35 vs. 50.35 ± 29.12; p < .001) had significantly higher improvement in VENC-MRI. Those who experienced late recurrence before post-RFCA MRI had significantly less improvement in LAA flow volume (∆VENC-MRI = 15.55 ± 41.41 vs. 26.18 ± 36.77; p = .011). Late recurrence and pre-RFCA VENC-MRI were significantly associated with ∆VENC-MRI after adjusting covariates. Patients who were AF before RFCA but maintained sinus rhythm after RFCA showed greatest improvement in VENC-MRI.

CONCLUSION

Effective rhythm control through RFCA can be associated with significant improvement in LAA hemodynamics. Low pre-RFCA VENC-MRI and absence of late recurrence were associated with greater improvement in LAA hemodynamics.

Cosmetic outcomes after transoral robotic thyroidectomy: Comparison with transaxillary, postauricular, and conventional approaches

OBJECTIVES

Transoral thyroidectomy does not involve neck incision, and its postoperative cosmetic outcome is thought to be superior to that of conventional thyroidectomy and other remote-access procedures. This study aimed to compare the cosmetic outcomes between transoral robotic thyroidectomy (TORT) and conventional transcervical thyroidectomy and two common remote-access robotic thyroidectomies via the transaxillary and postauricular approaches.

MATERIALS AND METHODS

We analyzed 160 patients who underwent TORT, robotic thyroidectomies via the transaxillary or postauricular approach, or conventional transcervical thyroidectomy (40 patients in each group). The postoperative cosmetic outcomes, including cosmetic satisfaction and scar consciousness scores, were evaluated using self-assessment cosmesis questionnaires at 3 months and 1 year postoperatively. The cosmesis index was defined as the sum of the percentage scores for cosmetic satisfaction and scar consciousness.

RESULTS

Cosmetic satisfaction scores, scar consciousness scores, and cosmesis indexes were significantly higher for the transoral, transaxillary, and postauricular approaches than the conventional approach at 3 months and 1 year postoperatively. There was a trend of better cosmetic outcomes, especially regarding scar consciousness, for the transoral and transaxillary approaches than for the postauricular approach, but the difference was not statistically significant.

CONCLUSION

Postoperative cosmesis of TORT, as well as the transaxillary and postauricular approaches, is superior to that of conventional thyroidectomy. The cosmetic outcomes of the transoral and transaxillary approaches seem to be better than those of the postauricular approach.

Premature ventricular contraction is associated with increased risk of atrial fibrillation: a nationwide population-based study

Premature ventricular contraction (PVC) and atrial fibrillation (AF) are common arrhythmias affecting 1–2% of the general population. During PVC, retrograde ventriculo-atrial activation can occur and act like an atrial ectopy. However, the clinical significance of this phenomenon is not fully understood. We aimed to elucidate whether the clinical diagnosis of PVC can increase the risk of new-onset AF. We performed a nationwide population-based analysis using the Korean National Health Insurance Service database. A total of 9,537,713 people without prior history of PVC and AF were identified. Among these people, 4135 developed PVC in 2009, and people with and without PVC were followed until 2018. People who had PVC showed an increased risk of new-onset AF as compared with people without PVC (hazard ratio [HR] = 2.705; 95% confidence interval [CI] = 2.428–3.013; p < 0.001). The risk of ischemic stroke was also significantly increased in people with PVC (HR 1.160; 95% CI 1.048–1.284; p = 0.0041). New-onset AF developed in 72 people (19.3%) among 374 people with PVC who had ischemic stroke during their follow-up. A significant interaction was observed between PVC and age with people < 65 years at greater risk of new-onset AF for having PVC. In this observational analysis, the risk of new-onset AF and ischemic stroke was increased in people with PVC. Additional evaluation to identify AF in people with PVC can be helpful.

Comparison of diagnostic accuracy of PET-derived myocardial blood flow parameters: A meta-analysis

BACKGROUND

Although absolute quantification of myocardial blood flow (MBF) by positron emission tomography provides additive diagnostic value to visual analysis of perfusion defect, diagnostic accuracy of different MBF parameters remain unclear.

METHODS

Clinical studies regarding the diagnostic accuracy of hyperemic MBF (hMBF), myocardial flow reserve (MFR) and/or relative flow reserve (RFR) were searched and systematically reviewed. On a per-vessel basis, pooled measures of the parameters' diagnostic performances were analyzed, regarding significant coronary stenosis defined by fractional flow reserve or diameter stenosis.

RESULTS

Ten studies (2,522 arteries from 1,099 patients) were finally included. Pooled sensitivity [95% confidence interval (CI)] was 0.853 (0.821-0.881) for hMBF, 0.755 (0.713-0.794) for MFR, and 0.636 (0.539-0.726) for RFR. Pooled specificity (95% CI) was 0.844 (0.827-0.860) for hMBF, 0.804 (0.784-0.824) for MFR, and 0.897 (0.860-0.926) for RFR. Pooled area under the curve ± standard error was 0.900 ± 0.020 for hMBF, 0.830 ± 0.026 for MFR, and 0.873 ± 0.048 for RFR.

CONCLUSIONS

hMBF showed the best sensitivity while RFR showed the best specificity in the diagnosis of significant coronary stenosis. MFR was less sensitive than hMBF and less specific than hMBF and RFR.

Early-Phase SPECT/CT for Diagnosing Osteomyelitis: A Retrospective Pilot Study

OBJECTIVE

The aim of this pilot study was to investigate the potential of early-phase single-photon emission computed tomography (SPECT)/computed tomography (CT) using technetium-99m methyl diphosphonate (^99mTc-MDP) for diagnosing osteomyelitis (OM).

MATERIALS AND METHODS

Twenty-one patients with suspected OM were enrolled retrospectively. Three-phase bone scan (TPBS), early-phase SPECT/CT (immediately after blood pool planar imaging), and delayed-phase SPECT/CT (immediately after delayed planar imaging) were performed. The final diagnoses were established through surgery or clinical follow-up for over 6 months. We compared three diagnostic criteria based on (I) TPBS alone, (II) combined TPBS and delayed-phase SPECT/CT, and (III) early-phase SPECT/CT alone.

RESULTS

OM was diagnosed in 11 of 21 patients (nine surgically and two clinically). Of the 11 OM patients, criterion-I, criterion-II, and criterion-III were positive in six, seven, and 10 patients, respectively. Of the 10 non-OM patients, criterion-I, criterion-II, and criterion-III were negative in five, five, and seven patients, respectively. The sensitivity/specificity/accuracy of criterion-I, criterion-II, and criterion-III for diagnosing OM were 54.5%/50.0%/55.0%, 63.6%/50.0%/57.1%, and 90.9%/70.0%/87.5%, respectively.

CONCLUSION

This pilot study demonstrated the potential of using the early-phase SPECT/CT to diagnose OM. Based on the results, prospective studies with a larger sample size should be conducted to confirm the efficacy of early-phase SPECT/CT.

Post-operative alarm signs in the rapid response system and hospital mortality after non-cardiac surgery

BACKGROUND

A variety of rapid response systems (RRSs) based on the systematic assessment of vital signs and laboratory tests have been developed to reduce hospital mortality through the early detection of alarm signs, while deterioration may still be reversible. This study aimed to determine the association between alarm signs and post-operative hospital mortality during post-operative days (POD) 0-3 in patients undergoing non-cardiac surgery.

METHODS

This retrospective observational study used data from the registry of a single tertiary academic hospital. The study population included patients who were ≥18 years old, admitted between 1 January 2013 and 30 June 2018 for non-cardiac surgery, and subsequently transferred to the general ward.

RESULTS

A total of 116 329 patients were included in the analysis. Among them, 10 099 patients (8.7%) showed positive alarm criteria and triggered the RRS in the post-operative ward during POD 0-3. In the multivariate logistic regression model, PaO₂ <55 mm Hg, SpO₂ <90%, and total CO₂ <15 mmol/L were associated with a 3.57-, 3.46-, and 12.53-fold increase in post-operative hospital mortality, respectively. Moreover, when compared to the no alarm signs group, patients with 1, 2, 3, and ≥4 alarm signs showed a 2.79-, 2.76-, 6.54-, and 20.02-fold increase in hospital mortality, respectively.

CONCLUSION

Increased post-operative hospital mortality was found to be associated with alarm signs detected by the RRS during POD 0-3. The post-operative alarm signs detected by the RRS may therefore be useful in determining high-risk patients who require medical interventions in the surgical ward.

Non-genetic risk factors for atrial fibrillation are equally important in both young and old age: A nationwide population-based study

AIMS

There are several non-genetic risk factors for new-onset atrial fibrillation, including age, sex, obesity, hypertension, diabetes, and alcohol consumption. However, whether these non-genetic risk factors have equal significance among different age groups is not known. We performed a nationwide population-based analysis to compare the clinical significance of non-genetic risk factors for new-onset atrial fibrillation in various age groups.

METHODS AND RESULTS

A total of 9,797,409 people without a prior diagnosis of atrial fibrillation who underwent a national health check-up in 2009 were included. During 80,130,090 person-years of follow-up, a total of 196,136 people were diagnosed with new-onset atrial fibrillation. The impact of non-genetic risk factors on new-onset atrial fibrillation was examined in different age groups. Obesity, male sex, heavy alcohol consumption, smoking, hypertension, diabetes and chronic kidney disease were associated with an increased risk of new-onset atrial fibrillation. With minor variations, these risk factors were consistently associated with the risk of new-onset atrial fibrillation among various age groups. Using these risk factors, we created a scoring system to predict future risk of new-onset atrial fibrillation in different age groups. In receiver operating characteristic curve analysis, the predictive value of these risk factors ranged between 0.556 and 0.603, and no significant trends were observed.

CONCLUSIONS

Non-genetic risk factors for new-onset atrial fibrillation may have a similar impact on different age groups. Except for sex, these non-genetic risk factors can be modifiable. Therefore, efforts to control non-genetic risk factors might have relevance for both the young and old.

2708. Genetic Structure of Streptococcus pneumoniae Isolated from Invasive Disease in Korea, 2014–2016

Background

The extended-valency pneumococcal conjugate vaccines (PCVs) were implemented into Korean national immunization program in 2014. This study investigated the change in genetic structures of Streptococcus pneumoniae causing invasive pneumococcal disease (IPD) in Korean children after 10- and 13-valent conjugate vaccine (PCV10 and PCV13, respectively) use.

Methods

Between January 2014 and December 2016, invasive isolates were collected from 23 hospitals throughout Korea. Cases of IPD were defined by isolating pneumococci from normally sterile sites. Each pneumococcal isolate was identified using standard microbiological techniques and serotyped by Quellung reaction. The multi-locus sequence typing (MLST) was analyzed for randomly selected isolates.

Results

A total of 91 pneumococcal isolates were analyzed. Common serotypes were 10A (18.7%), 12F (11.0%), 15A (9.9%), 19A (9.9%), 15B/C (7.7%), 23A (6.6%), 35B (5.5%), and 23B (4.4%). The isolates belonged to 38 sequence types (STs), including 4 newly discovered STs. Of the 4 clonal complexes (CCs), 3 clonal complexes were antibiotic-resistant international clones. CC166 (11.9%) were associated with non-vaccine serotypes (NVTs; 11A, 15B/C, 23A, and 13). Serotypes of CC320 (10.9%) comprised of serotype 19A and 19F. The main serotypes responsible for CC81 (10.9%) were serogroup 15. New serotype-ST combinations were observed, especially in serotype 13 and serogroup 15. Also, a possibility of capsular switch event was noted between serogroup 6 and serogroup 15A.).

Conclusion

The introduction of extended-valency PCVs has resulted in the change of the genetic structure of pneumococcal isolates in Korean children. This study demonstrates that selective pressure from PCV10/13 caused predominant serotypes to be NVTs and genetic changes such as capsular switch events.

Disclosures

All authors: No reported disclosures.

638. Comparative Genomics of Mycoplasma pneumoniae Isolated From Children with Pneumonia: South Korea, 2010–2016

Background

This study applied high-throughput whole-genome sequencing (WGS) technologies to investigate the comparative genomics of 30 M. pneumoniae strains isolated from children with pneumonia in South Korea during two epidemics from 2010 to 2016 in comparison with a global collection of 48 Mycoplasma pneumoniae strains which includes seven countries ranging from 1944 to 2017.

Methods

A total number of 30 M. pneumoniae strains were selected for whole-genome sequence analysis from two epidemics, 2010–2012 and 2014–2016. Next-generation sequencing (NGS) of all M. pneumoniae strains was performed using the Illumina MiSeq desktop sequencer. Comparative genomic analysis was performed using BLAST Ring Image Generator (BRIG), MAUVE, MAFFT, CLC Phylogeny Module, SnpEff, and Pathosystems Resource Integration Center (PATRIC).

Results

The 30 Korean strains had approximately 40% GC content and ranged from 815,686 to 818,669 base pairs, coding for a total of 809 to 828 genes. Overall, BRIG revealed 99% to>99% similarity among strains. The genomic similarity dropped to approximately 95% in the P1 type 2 strains when aligned to the reference M129 genome, which corresponded to the region of the p1 gene. MAUVE detected four subtype-specific of which were all hypothetical proteins except for one tRNA insertion in all P1 type 1 strains. eBURST analysis demonstrated two clonal complexes which are accordant with the known P1 typing, with higher diversity among P1 type 2 strains. The phylogenetic tree constructed with 78 genomes including 48 genomes outside Korea, formed three clusters, in which the sequence type 3 strains from Korea were divided into two P1 type 1 clusters.

Conclusion

The comparative genomics of the 78 M. pneumoniae strains including 30 strains from Korea by WGS reveals structural diversity and phylogenetic associations, even though the similarity across the strains was very high.

Disclosures

All authors: No reported disclosures.

Primary Histiocytic Sarcoma Presenting as a Breast Mass: A Case Report

Histiocytic sarcoma is a rare hematologic malignancy, with very few cases of primary histiocytic sarcoma of the breast described in English scientific literature. Herein, we describe a case of primary histiocytic sarcoma of the breast in a 75-year-old woman, with no clinical history of malignant tumors, who presented with a palpable solitary breast mass. Microscopically, the resected breast mass showed large pleomorphic cells, some multinucleated giant cells, and admixed inflammatory components. The pleomorphic tumor cells further showed a diffuse, noncohesive growth pattern, an abundant eosinophilic cytoplasm, and strong and diffuse immunoreactivity for cluster of differentiation (CD) 68 and CD163. Furthermore, a whole-body positron-emission tomography/computed tomography using deoxy-2-[¹⁸F]fluoro-D-glucose performed after surgery showed no other masses or lesions. After surgical excision, the patient was followed up, and no evidence of tumor recurrence or metastasis was noted.

Psoas muscle fluorine-18-labelled fluoro-2-deoxy-d-glucose uptake associated with the incidence of existing and incipient metabolic derangement

BACKGROUND

Skeletal muscle glucose utilization is an important component of whole-body glucose consumption in normal humans. Fluorine-18-labelled fluoro-2-deoxy-d-glucose (¹⁸ F-FDG) is a non-invasive molecular imaging probe for evaluating tissue glucose utilization. It remains unclear whether or not ¹⁸ F-FDG uptake by skeletal muscle has utility as a biomarker for metabolic derangement. We investigated the utility of measurement of muscle ¹⁸ F-FDG positron emission tomography/computed tomography uptake as a surrogate marker for existing and incipient metabolic abnormalities.

METHODS

Fluorine-18-labelled fluoro-2-deoxy-d-glucose (¹⁸ F-FDG) uptakes of insulin-sensitive organs (liver, pancreas, mesenteric visceral fat, psoas muscle, and abdominal subcutaneous fat) and their association with metabolic abnormalities were evaluated in an experimental group comprising 91 men and 66 women (mean age 49.9 ± 11.1 years). In this cross-sectional cohort, we assessed the predictive power of the optimal cut-off ¹⁸ F-FDG uptake [maximum standardized uptake value (SUV_max )]. We confirmed its feasibility and reliability for diagnosis of existing and incipient metabolic derangement in the validation group (longitudinal cohort comprising 91 men and 67 women; mean age 52.6 ± 7.9 years).

RESULTS

Fluorine-18-labelled fluoro-2-deoxy-d-glucose (¹⁸ F-FDG) uptake (SUV_max ) of psoas muscle was strongly correlated with clinical metabolic parameters in the experimental group. It was positively correlated with waist circumference, body mass index, fasting glucose, triglyceride, systolic and diastolic pressure, and negatively correlated with high-density lipoprotein cholesterol levels (for all, P < 0.05). SUV_max of the psoas muscle also showed the best area under the curve value (0.779) as a predictor of metabolic syndrome (MetS) in the experimental group. Using the optimal cut-off SUV_max of 1.34, the sensitivity, specificity, accuracy, positive, and negative predictive value for predicting existing MetS in the experimental group were 70.0%, 84.6%, 80.9%, 60.9%, and 89.2%, respectively. In the validation group, corresponding values were 47.6%, 92.3%, 86.1%, 50.0%, and 91.6%, respectively. Existing and incipient MetS were significantly higher in subjects with high ¹⁸ F-FDG uptake by the psoas muscle (SUV_max  > 1.34). Subjects with higher psoas muscle SUV_max had a 3.3-fold increased risk of developing MetS (P = 0.017).

CONCLUSIONS

Fluorine-18-labelled fluoro-2-deoxy-d-glucose (¹⁸ F-FDG) uptake of psoas muscle is a promising surrogate marker for existing and incipient metabolic derangement.