Immune Responses After Vaccination With Primary 2-Dose ChAdOx1 Plus a Booster of BNT162b2 or Vaccination With Primary 2-Dose BNT162b2 Plus a Booster of BNT162b2 and the Occurrence of Omicron Breakthrough Infection.

BACKGROUND: Before the omicron era, health care workers were usually vaccinated with either the primary 2-dose ChAdOx1 nCoV-19 (Oxford-AstraZeneca) series plus a booster dose of BNT162b2 (Pfizer-BioNTech) (CCB group) or the primary 2-dose BNT162b2 series plus a booster dose of BNT162b2 (BBB group) in Korea. METHODS: The two groups were compared using quantification of the surrogate virus neutralization test for wild type severe acute respiratory syndrome coronavirus 2 (SVNT-WT), the omicron variant (SVNT-O), spike-specific IgG, and interferon-gamma (IFN-γ), as well as the omicron breakthrough infection cases. RESULTS: There were 113 participants enrolled in the CCB group and 51 enrolled in the BBB group. Before and after booster vaccination, the median SVNT-WT and SVNT-O values were lower in the CCB (SVNT-WT [before-after]: 72.02-97.61%, SVNT-O: 15.18-42.29%) group than in the BBB group (SVNT-WT: 89.19-98.11%, SVNT-O: 23.58-68.56%; all P < 0.001). Although the median IgG concentrations were different between the CCB and BBB groups after the primary series (2.677 vs. 4.700 AU/mL, respectively, P < 0.001), they were not different between the two groups after the booster vaccination (7.246 vs. 7.979 AU/mL, respectively, P = 0.108). In addition, the median IFN-γ concentration was higher in the BBB group than in the CCB group (550.5 and 387.5 mIU/mL, respectively, P = 0.014). There was also a difference in the cumulative incidence curves over time (CCB group 50.0% vs. BBB group 41.8%; P = 0.045), indicating that breakthrough infection occurred faster in the CCB group. CONCLUSION: The cellular and humoral immune responses were low in the CCB group so that the breakthrough infection occurred faster in the CCB group than in the BBB group.

Ensemble clustering for step data via binning.

This paper considers the clustering problem of physical step count data recorded on wearable devices. Clustering step data give an insight into an individual's activity status and further provide the groundwork for health-related policies. However, classical methods, such as K-means clustering and hierarchical clustering, are not suitable for step count data that are typically high-dimensional and zero-inflated. This paper presents a new clustering method for step data based on a novel combination of ensemble clustering and binning. We first construct multiple sets of binned data by changing the size and starting position of the bin, and then merge the clustering results from the binned data using a voting method. The advantage of binning, as a critical component, is that it substantially reduces the dimension of the original data while preserving the essential characteristics of the data. As a result, combining clustering results from multiple binned data can provide an improved clustering result that reflects both local and global structures of the data. Simulation studies and real data analysis were carried out to evaluate the empirical performance of the proposed method and demonstrate its general utility.

A GEE approach to estimating accuracy and its confidence intervals for correlated data.

In this paper, we provide a method for constructing confidence interval for accuracy in correlated observations, where one sample of patients is being rated by two or more diagnostic tests. Confidence intervals for other measures of diagnostic tests, such as sensitivity, specificity, positive predictive value, and negative predictive value, have already been developed for clustered or correlated observations using the generalized estimating equations (GEE) method. Here, we use the GEE and delta-method to construct confidence intervals for accuracy, the proportion of patients who are correctly classified. Simulation results verify that the estimated confidence intervals exhibit consistent/appropriate coverage rates.

Background parenchymal enhancement on breast MRI: association with recurrence-free survival in patients with newly diagnosed invasive breast cancer.

PURPOSE: To determine whether BPE in preoperative breast MRI influences patients' recurrence-free survival (RFS). METHODS: Between February 2010 and December 2011, 804 consecutive women with invasive breast cancer who had undergone preoperative breast MRI and curative cancer surgery were identified. BPE was visually graded by two reviewers. We determined the correlation between BPE grade and other clinicopathological variables, including age, adjuvant therapy, menopausal status, histologic grade, T stage, N stage, lymphovascular invasion, molecular subtype, surgical margin status, and mammographic density. A Cox proportional hazards model was used to analyze the effects of clinicopathological variables and radiological findings (BPE grade, mammographic density) on RFS. RESULTS: High BPE was associated with premenopausal status (Ps < 0.0001), higher mammographic density (Ps < 0.0001), progesterone receptor positivity (Ps = 0.039, 0.007, respectively), presence of lymphovascular invasion (Ps = 0.008, 0.001, respectively), and close surgical margin (Ps < 0.0001). Recurrences were observed in 75 patients after a mean follow-up period of 61.8 months (range 4-81 months). Non-minimal BPE grade (RFS hazard ratio = 3.086, P = 0.003 for reader 1; RFS hazard ratio = 2.221, P = 0.075 for reader 2) and T3 stage were associated with worse outcomes in postmenopausal women. In premenopausal women, non-minimal BPE grade by readers 1 and 2 did not affect the patients' outcomes. CONCLUSIONS: Increased BPE on preoperative breast MRI in postmenopausal women has potential as a predictor of poor RFS.

Reducing Artifacts during Arterial Phase of Gadoxetate Disodium-enhanced MR Imaging: Dilution Method versus Reduced Injection Rate.

Purpose To compare two contrast material-administration protocols (dilution vs slow injection) in terms of their effectiveness in arterial phase artifact reduction at gadoxetic acid-enhanced magnetic resonance (MR) imaging. Materials and Methods This HIPAA-compliant retrospective case-controlled cohort study was approved by the institutional review board, with a waiver of informed patient consent. A total of 318 consecutive patients undergoing gadoxetic acid-enhanced MR imaging were placed into one of two subcohorts of 159 consecutive patients each: the dilution subcohort (gadoxetic acid was diluted 1:1 with saline and injected at a rate of 2.0 mL/sec) and the slow injection subcohort (gadoxetic acid was not diluted and was injected at a rate of 1.0 mL/sec). Eighty-nine patients in the dilution subcohort also underwent follow-up MR imaging with the slow injection method, and 34 patients in the slow injection subcohort underwent follow-up MR imaging with the dilution method. Both patient- and image-based analyses, as well as intraindividual analysis, were used to compare two parameters-mean artifact score rated by two observers using a five-point scale and frequency of severe artifact-between the dilution and slow injection subcohorts with the Wilcoxon Mann-Whitney test, χ2 test, and generalized estimating equation. Results In both patient- and image-based analyses, the mean artifact score and frequency of severe artifact were lower in the dilution subcohort (mean, 1.46% and 3.8% [six of 159]) than in the slow injection subcohort (mean, 1.95% and 15.1% [24 of 159]) (P ≤ .001 and P < .001, respectively). In intraindividual analysis, both variables were also decreased in the dilution subcohort (P = .007 and P = .001, respectively). We found the two variables to be significantly increased in the slow injection subcohort when compared with that in the dilution subcohort for three different MR platforms (P < .05). Conclusion In comparison with slow injection of undiluted contrast material at a rate of 1.0 mL/sec, gadoxetic acid diluted to 50% and injected at a rate of 2 mL/sec had a significantly less severe ghosting artifact in the arterial phase of gadoxetic acid-enhanced MR imaging. © RSNA, 2016 Online supplemental material is available for this article.

Breast Cancer Heterogeneity: MR Imaging Texture Analysis and Survival Outcomes.

Purpose To determine the relationship between tumor heterogeneity assessed by means of magnetic resonance (MR) imaging texture analysis and survival outcomes in patients with primary breast cancer. Materials and Methods Between January and August 2010, texture analysis of the entire primary breast tumor in 203 patients was performed with T2-weighted and contrast material-enhanced T1-weighted subtraction MR imaging for preoperative staging. Histogram-based uniformity and entropy were calculated. To dichotomize texture parameters for survival analysis, the 10-fold cross-validation method was used to determine cutoff points in the receiver operating characteristic curve analysis. The Cox proportional hazards model and Kaplan-Meier analysis were used to determine the association of texture parameters and morphologic or volumetric information obtained at MR imaging or clinical-pathologic variables with recurrence-free survival (RFS). Results There were 26 events, including 22 recurrences (10 local-regional and 12 distant) and four deaths, with a mean follow-up time of 56.2 months. In multivariate analysis, a higher N stage (RFS hazard ratio, 11.15 [N3 stage]; P = .002, Bonferroni-adjusted α = .0167), triple-negative subtype (RFS hazard ratio, 16.91; P < .001, Bonferroni-adjusted α = .0167), high risk of T1 entropy (less than the cutoff values [mean, 5.057; range, 5.022-5.167], RFS hazard ratio, 4.55; P = .018), and T2 entropy (equal to or higher than the cutoff values [mean, 6.013; range, 6.004-6.035], RFS hazard ratio = 9.84; P = .001) were associated with worse outcomes. Conclusion Patients with breast cancers that appeared more heterogeneous on T2-weighted images (higher entropy) and those that appeared less heterogeneous on contrast-enhanced T1-weighted subtraction images (lower entropy) exhibited poorer RFS. © RSNA, 2016 Online supplemental material is available for this article.

Baseline Wall Thickness Is Lower in Mucosa-Healed Segments 1 Year After Infliximab in Pediatric Crohn Disease Patients.

OBJECTIVES: We aimed to quantitatively investigate the therapeutic response to combined immunosuppression treatment by magnetic resonance enterography (MRE) in active luminal Crohn disease (CD) in the pediatric population. METHODS: Pediatric patients with moderate-to-severe luminal CD, who received scheduled infliximab and azathioprine, were included in this preliminary study. Ileocolonoscopy and MRE were performed at baseline and at 1 year, and Simple Endoscopic Score for Crohn's Disease (SES-CD) and Magnetic Resonance Index of Activity (MaRIA) scores were calculated. The correlation between SES-CD and MaRIA scores were investigated with analysis per person and per segment. RESULTS: A total of 167 segments from 17 patients were evaluated by both Ileocolonoscopy and MRE. SES-CD and MaRIA scores showed significant correlations on both per-person analysis (ρ = 0.699, P < 0.001) and per-segment analysis (ρ = 0.596, P < 0.001). Analysis according to ileocolonic location of each segment revealed that the correlation strength was strongest in the right colon (ρ = 0.653, P < 0.001), whereas the correlation in the rectum was statistically insignificant (ρ = 0.29, P = 0.096). A comparative analysis of MaRIA components revealed a significantly thinner bowel wall thickness at baseline in endoscopically healed segments (50/65) compared with unhealed segments (15/65) (median 4.3 vs 7.2 mm, P = 0.036). CONCLUSIONS: Therapeutic response to combined immunosuppression at 1 year assessed by MRE correlates with ileocolonoscopy in pediatric patients with CD. Bowel wall thickness of the involved segments at baseline may affect treatment response to combined immunosuppression.

Effect of motivated physicians and elderly patients with hypertension or type 2 diabetes mellitus in prepared communities on health behaviours and outcomes: A population-based PS matched retrospective cohort study during five-year follow-up period.

Effective chronic disease management requires the active participation of patients, communities, and physicians. The objective of this study was to estimate the effectiveness of the Community-based Registration and Management for elderly patients with Hypertension or Type 2 Diabetes mellitus Project (CRMHDP) by using motivated primary care physicians and patients supported by prepared communities, to utilise healthcare and health outcomes in four cities in South Korea. We conducted a propensity score-matched retrospective cohort study using 2010-2011 as the baseline years, alongside a follow-up period until 2015/2016, based on the Korean National Health Insurance database. Both a CRMHDP group (n = 46,865) and a control group (n = 93,730) were applied against healthcare utilisation and difference-in-differences estimations were performed. For the health outcome analysis, the intervention group (n = 27,242) and control group (n = 54,484) were analysed using the Kaplan-Meier method and Cox proportional hazard regression. Results: The difference-in-differences estimation of the average annual clinic visits per person and the average annual days covered were 1.26 (95% confidence interval, 1.13-1.39) and 22.97 (95% CI, 20.91-25.03), respectively, between the intervention and control groups. The adjusted hazard ratio for death in the intervention group, compared to the control group, was 0.90 (95% CI, 0.86-0.93). For stroke and chronic renal failure, the adjusted hazard ratios for the intervention group compared to the control group were 0.94 (95% CI, 0.88-0.99) and 0.80 (95% CI 0.73-0.89), respectively. Our study suggests that for effective chronic disease management both elderly patients and physicians need to be motivated by community support.

Zero-Inflated Time Series Clustering Via Ensemble Thick-Pen Transform.

This study develops a new clustering method for high-dimensional zero-inflated time series data. The proposed method is based on thick-pen transform (TPT), in which the basic idea is to draw along the data with a pen of a given thickness. Since TPT is a multi-scale visualization technique, it provides some information on the temporal tendency of neighborhood values. We introduce a modified TPT, termed 'ensemble TPT (e-TPT)', to enhance the temporal resolution of zero-inflated time series data that is crucial for clustering them efficiently. Furthermore, this study defines a modified similarity measure for zero-inflated time series data considering e-TPT and proposes an efficient iterative clustering algorithm suitable for the proposed measure. Finally, the effectiveness of the proposed method is demonstrated by simulation experiments and two real datasets: step count data and newly confirmed COVID-19 case data.

Association between the incidence of type 1 diabetes mellitus and tuberculosis or bacillus Calmette-Guérin immunization in children and adolescents.

PURPOSE: The correlation between the incidence of type 1 diabetes mellitus (T1DM) and tuberculosis or bacillus Calmette-Guérin (BCG) vaccination rate in individuals aged <15 years was investigated using worldwide data. METHODS: The incidence of T1DM, rate of BCG vaccination, and incidence of tuberculosis were obtained from the Diabetes Atlas 9th edition of the International Diabetes Federation and the Global Health Observatory data repository of the World Health Organization. Gross domestic product (GDP) per capita and population data by country were obtained from the World Bank and United Nations, respectively. RESULTS: GDP per capita negatively correlated with the incidence of tuberculosis and positively correlated with the incidence of T1DM (coefficient=-0.630 and 0.596, respectively; all P<0.001). The incidence of T1DM and tuberculosis was significantly associated with the Organisation for Economic Cooperation and Development (OECD) status (P<0.001). After adjusting for GDP per capita, regional grouping, and OECD status, the incidence of T1DM negatively correlated with that of tuberculosis (R2 =0.729, P=0.009). However, there was no association between the BCG vaccination rate and incidence of T1DM (P=0.890). CONCLUSION: There was a negative correlation between the incidence of tuberculosis and T1DM in children and adolescents aged <15 years at the country level.

Safety of urgent surgery for the patients with proximal femur fracture treated with platelet aggregation inhibitors: a propensity-score matching analysis.

INTRODUCTION: To compare the various perioperative outcomes in an urgent surgery setting among patients with proximal femur fracture (PFF) who received platelet aggregation inhibitors (PAIs) and those who did not. METHODS: We retrospectively reviewed the data of 1,838 patients who underwent surgery for PFF between January 2011 and January 2021. We conducted 1:1 propensity-score matching and compared the perioperative outcomes, including operation time, postoperative complications, hospital stay, mortality, and variables related to bleeding risk (e.g., number of transfusion profiles, hemoglobin levels, and laboratory data, including coagulation battery). RESULTS: Of the 492 patients who were treated with PAIs, 484 were 1:1 matched to the untreated control group. The PAI group showed shorter operation time than the matched control group (72.3 min for PAI vs. 77.7 min for control; P = 0.041), and the control group showed more pulmonary thromboembolism (0.2% for PAI vs 1.7% for control; P = 0.046) than the PAI group. The other complications and length of hospital stay, mortality rate, transfusion profile, and the laboratory test (except preoperative international normalized ratio, INR) showed no significant difference between the groups. Subgroup analyses of the patients treated with only aspirin (aspirin: 306, matched control: 306), only clopidogrel (clopidogrel: 100, matched control: 100), and others who were treated with dual anticoagulation (dual anticoagulation: 78, matched control: 78) showed no significant differences in perioperative outcomes among the groups. CONCLUSION: The patients who were treated with PAI could undergo PFF surgery safely without delay, which led to no significant difference in operation time, postoperative complication risk, perioperative blood transfusion, and variables related to bleeding risk. Therefore, we believe that it is unnecessary to delay surgery for patients with PFF who receive PAI.

Comparison between Conventional Breath-hold and Respiratory-triggered Magnetic Resonance Cholangiopancreatography with and without Compressed Sensing: Cross-sectional Study.

AIM: The application of compressed sensing (CS) has enabled breath-hold 3D-MRCP with a shorter acquisition time in clinical practice. INTRODUCTION: To compare the image quality of breath-hold (BH) and respiratory-triggered (RT) 3D-MRCP with or without CS application in the same study population. METHODS: In this retrospective study, from February to July 2020, a total of 98 consecutive patients underwent four different acquisition types of 3D-MRCP.; 1) BH MRCP with the generalized autocalibrating partially parallel acquisition (GRAPPA) (BH-GRAPPA), 2) RT-GRAPPA-MRCP, 3) RT-CS-MRCP and 4) BH-CS-MRCP. Relative contrast of common bile duct, 5-scale visibility score of biliary pancreatic ducts, 3-scale artifact score and 5-scale overall image quality score were evaluated by two abdominal radiologists. RESULTS: Relative contrast value was significantly higher in BH-CS or RT-CS than in RT-GRAPPA (0.90 ± 0.057 and 0.89 ± 0.079, respectively, vs. 0.82 ± 0.071, p < 0.01) or BH-GRAPPA (vs. 0.77 ± 0.080, p < 0.01). The area affected by artifact was significantly lower in BH-CS among 4 MRCPs (p < 0.08). Overall image quality score in BH-CS was significantly higher than BH-GRAPPA (3.40 vs. 2.71, p < 0.01). There were no significant differences between RT-GRAPPA and BH-CS (vs. 3.13, p = 0.67) in overall image quality. CONCLUSION: In this study, our results revealed BH-CS had higher relative contrast and comparable or superior image quality among four MRCP sequences.

Prediction of Deterioration of Left Ventricular Function Using 3-Dimensional Speckle-Tracking Echocardiography in Patients With Left Bundle-Branch Block.

Background Previous studies have demonstrated that 2-dimensional (2D) global longitudinal strain (GLS) is associated with cardiovascular outcomes in patients with left bundle-branch block. However, the predictive value of 3-dimensional (3D) speckle-tracking echocardiography has not yet been investigated in these patients. Methods and Results The authors retrospectively identified 290 patients with left bundle-branch block who underwent echocardiography more than twice. Using speckle-tracking echocardiography, 2D-GLS, 3D-GLS, 3D-global circumferential strain, 3D global radial strain, and 3D global area strain were acquired. The association between 2D and 3D strains and the follow-up left ventricular (LV) ejection fraction (LVEF) was analyzed. The study population was divided into 2 sets: a group with preserved LVEF (baseline LVEF ≥40%) and a group with reduced LVEF (baseline LVEF <40%). After a median follow-up of 29.1 months (interquartile range, 13.1-53.0 months), 14.9% of patients progressed to LV dysfunction in the group with preserved LVEF, and 51.0% of patients showed improved LV function in the group with reduced LVEF. Multivariable analysis of 2D and 3D strains revealed that higher 2D-GLS (odds ratio [OR], 0.65 [95% CI, 0.54-0.78], P<0.001) was highly associated with maintaining LVEF in patients with preserved LVEF. However, a lower 3D-global circumferential strain (OR, 0.61 [95% CI, 0.47-0.78], P<0.001) showed a strong association with persistently reduced LVEF in patients with reduced LVEF. Conclusions Although 2D-GLS showed a powerful predictive value for the deterioration of LV function in the preserved LVEF group, 3D strain, especially 3D-global circumferential strain, can be helpful to predict consistent LV dysfunction in patients with left bundle-branch block who have reduced LVEF.

A study on changes in lung function, neutralizing antibodies, and symptoms of adult patients hospitalized with COVID-19.

BACKGROUND/AIMS: To identify changes in symptoms and pulmonary sequelae in patients with coronavirus disease 2019 (COVID-19). METHODS: Patients with COVID-19 hospitalized at seven university hospitals in Korea between February 2020 and February 2021 were enrolled, provided they had ≥ 1 outpatient follow-up visit. Between January 11 and March 9, 2021 (study period), residual symptom investigations, chest computed tomography (CT) scans, pulmonary function tests (PFT), and neutralizing antibody tests (NAb) were performed at the outpatient visit (cross-sectional design). Additionally, data from patients who already had follow-up outpatient visits before the study period were collected retrospectively. RESULTS: Investigation of residual symptoms, chest CT scans, PFT, and NAb were performed in 84, 35, 31, and 27 patients, respectively. After 6 months, chest discomfort and dyspnea persisted in 26.7% (4/15) and 33.3% (5/15) patients, respectively, and 40.0% (6/15) and 26.7% (4/15) patients experienced financial loss and emotional distress, respectively. When the ratio of later CT score to previous ones was calculated for each patient between three different time intervals (1-14, 15-60, and 61-365 days), the median values were 0.65 (the second interval to the first), 0.39 (the third to the second), and 0.20 (the third to the first), indicating that CT score decreases with time. In the high-severity group, the ratio was lower than in the low-severity group. CONCLUSION: In COVID-19 survivors, chest CT score recovers over time, but recovery is slower in severely ill patients. Subjects complained of various ongoing symptoms and socioeconomic problems for several months after recovery.

Bootstrap aggregated classification for sparse functional data.

Sparse functional data are commonly observed in real-data analyzes. For such data, we propose a new classification method based on functional principal component analysis (FPCA) and bootstrap aggregating. Bootstrap aggregating is believed to improve the single classifier. In this paper, we apply this belief to an FPCA based classification, and compare the classification performance with that of the single classifiers. The simulation results show that the proposed method performs better than the conventional single classifiers. We then conduct two real-data analyzes.

Neuromuscular blockade in mechanically ventilated pneumonia patients with moderate to severe hypoxemia: A multicenter retrospective study.

BACKGROUND/PURPOSE: The benefit of neuromuscular blockades (NMBs) in critically ill patients receiving mechanical ventilation remains uncertain. Therefore, we aimed to investigate whether NMB use is associated with improved survival of mechanically ventilated pneumonia patients with moderate to severe hypoxemia. METHODS: This retrospective multicenter study was conducted at five university-affiliated hospitals. Data of pneumonia patients aged 18 years and older who received mechanical ventilation between January 1, 2011, and December 31, 2020, were analyzed. RESULTS: In a total of 1,130 patients, the mean patient age was 73.1 years (SD±12.6), and the overall mortality rate at 30 d was 29.5% (n = 333). NMB users had a higher 30 d mortality rate than NMB nonusers (33.9% vs. 26.8%, P = 0.014). After PS matching, the 30 d mortality rate was not significantly different between NMB users and nonusers (33.4% vs. 27.8%, p = 0.089). However, 90 d mortality rate was significantly increased in NMB users (39.7% vs. 31.9%, p = 0.021). Univariable Cox proportional hazard regression analyses showed that NMB use ≥ 3 d was significant risk factor for the 90 d mortality than those with < 3 d use (90 d mortality HR 1.39 [95% CI: 1.01-1.91], P = 0.045). CONCLUSIONS: NMB use was not associated with lower 30 d mortality among mechanically ventilated pneumonia patients with moderate to severe hypoxemia. Rather, NMB users had higher 90 d mortality, furthermore, and NMB use ≥ 3 d was associated with a higher risk of long-term mortality compared to NMB use < 3 d. Therefore, care should be taken to avoid extended use of NMB in critically ill pneumonia patients during mechanical ventilation.

Ultrasonographic characteristics of Hürthle cell neoplasms: prediction of malignancy.

PURPOSE: This study investigated the ultrasound (US) features of malignancy in patients with Hürthle cell neoplasms (HCNs) of the thyroid gland. METHODS: The present study included 139 HCNs that had undergone surgical excision at a single institution from 1996 to 2020 and had preoperative US images. The sonographic characteristics of HCNs were correlated with their pathological results. The US findings associated with malignancy were explored using logistic regression analysis, and the diagnostic performance and cutoff were assessed using receiver operating characteristic analysis. RESULTS: The most common US findings of HCNs were a solid content (76.3%), oval to round shape (100%), hypoechogenicity (70.5%), a smooth margin (95.0%), the halo sign (90.6%), and no calcifications (93.5%). HCNs were commonly smaller in pathologic measurements than in US measurements (smaller, same, and greater than US measurements in 60.4%, 21.6%, and 18.0% of HCNs, respectively; P<0.001). On US, malignant nodules were significantly larger than benign nodules (3.4±1.6 cm vs. 2.2±1.2 cm, P<0.001). Multiple logistic regression showed that the US tumor size was an independent predictor of malignancy (P=0.001; odds ratio, 1.730 for a 1-cm increase [95% confidence interval, 1.258 to 2.375]). The best cutoff US tumor size for predicting malignancy was 3.35 cm (sensitivity, 53.1%; specificity, 87.9%). CONCLUSION: The US tumor size was found to be an independent predictor of malignancy in HCNs, and a US tumor size >3.35 cm might be used as a criterion to suggest malignancy. The size of HCNs often showed discrepancies between US and pathologic measurements.

Relationship between SARS-CoV-2 antibody titer and the severity of COVID-19.

BACKGROUND: It remains unclear whether high titers of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies aggravate clinical manifestations in patients or whether severe clinical manifestations result in high antibody titers. Thus, we investigated the cause-effect relationship between SARS-CoV-2 antibody titers and disease severity. METHODS: We prospectively enrolled patients admitted with the diagnosis of coronavirus disease-19 (COVID-19) from February 2020 to August 2020. We measured SARS-CoV-2 antibody titers, namely anti-receptor-binding domain (RBD) antibody and neutralizing antibody (NAb), from blood samples and calculated the chest radiograph (CXR) scores of the patients to evaluate the severity of COVID-19. RESULTS: Overall, 40 patients with COVID-19 were enrolled. Pneumonia was observed in more than half of the patients (25/40, 60%). SARS-CoV-2 antibody titers were higher in patients who were aged >60 years (anti-RBD antibodies, P = 0.003 and NAb, P = 0.009), presented with pneumonia (P = 0.006 and 0.007, respectively), and required oxygen therapy (P = 0.003 and 0.004, respectively) than in those who were not. CXR scores peaked (at 15-21 days after the onset of symptoms) statistically significantly earlier than SARS-CoV-2 antibody titers (at 22-30 days for NAb and at 31-70 days for anti-RBD antibody). There was a close correlation between the maximum CXR score and the maximum SAR-CoV-2 antibody titer. CONCLUSIONS: Based on the comparison of the peak time of SARS-CoV-2 antibody titers with the CXR score after symptom onset, we suggest that severe clinical manifestations result in high titers of SARS-CoV-2 antibodies.

Clinical outcomes of posttransplantation diabetes mellitus in kidney transplantation recipients: a nationwide population-based cohort study in Korea.

Posttransplantation diabetes mellitus (PTDM) is an important metabolic complication after KT that causes graft failure and cardiovascular complications in kidney transplantation (KT) recipients. Using the national claim data of South Korea, 7612 KT recipients between 2009 and 2017 were analyzed. PTDM was defined as a consecutive 30-day prescription history of antidiabetic medication after KT. Among these patients, 24.7% were diagnosed with PTDM, and 51.9% were diagnosed within 6 months after KT. Compared to patients without PTDM, those with PTDM were older, more likely to be men, more likely to be diagnosed with hypertension and cardio-cerebrovascular disease, and experienced more rejection episodes requiring high-dose steroid treatment after KT. During the follow-up, 607 DCGFs, 230 DWGFs, 244 MACEs, and 260 all-cause mortality events occurred. Patients with PTDM showed a higher risk of DCGF (adjusted hazard ratio [aHR] 1.49; 95% confidence interval [CI] 1.22-1.82; P < 0.001) and MACEs (aHR 1.76; 95% CI 1.33-2.31; P < 0.001) than patients without PTDM. The risks for all clinical outcomes were higher in the insulin group than in the non-use insulin group. PTDM in KT recipients resulted in both worse allograft and patient outcomes represented by DCGF and MACE, especially in patients needing insulin treatment.