A rare goblet cell adenocarcinoma arising from Barrett’s esophagus: the first reported case in the esophagus

Goblet cell adenocarcinoma (GCA) is a rare and distinctive amphicrine tumor comprised of goblet-like mucinous cells and neuroendocrine cells. It is believed to originate from pluripotent stem cells located at the base of crypts. GCA predominantly arises from the appendix, with a few reported cases in extra-appendiceal locations such as the colorectum, small intestine, and stomach. In this case report, we present a unique instance of a 64-year-old male who initially received a diagnosis of neuroendocrine carcinoma in the distal esophagus based on biopsy but, following resection, was subsequently re-diagnosed with GCA arising from Barrett’s esophagus.

Statins as a possible factor affecting fluoroquinolone resistance of coagulase-negative Staphylococcus in the conjunctiva: a case-control study / 고신대학교의과대학학술지

Background@#Conjunctival bacterial flora is a common cause of endophthalmitis after ophthalmic procedures. This study investigated the conjunctival bacterial flora, especially coagulase-negative Staphylococcus (CoNS), and their antibiotic sensitivity in patients who underwent ophthalmic procedures. Factors related to fluoroquinolone resistance were also investigated. @*Methods@#In total, 167 samples were analyzed from 135 patients who underwent cataract surgery or intravitreal injection at Kosin University Gospel Hospital between April 14, 2014, and September 29, 2016. Bacterial identification was performed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry or VITEK 2 equipment. Antibiotic sensitivity tests were performed using an AST-P600 card with VITEK 2 equipment. Clinical information was extracted from patients’ medical records. Sixty-eight individuals with conjunctival flora containing CoNS were classified into the fluoroquinolone-sensitive and fluoroquinolone-resistant CoNS groups, and their characteristics were compared. @*Results@#A total of 192 isolates of Gram-positive bacteria were identified, including Staphylococcus epidermidis (33.3%), Corynebacterium spp. (18.8%), and CoNS other than S. epidermidis (9.2%). Of the 106 CoNS isolates, 68.9%, 69.8%, and 58.5% were sensitive to ciprofloxacin, levofloxacin, and norfloxacin, respectively. In patients with CoNS, statin use within 3 months before sample collection was significantly associated with fluoroquinolone resistance (p=0.016). Statin use was a significant risk factor for fluoroquinolone resistance in multivariate logistic regression analysis (odds ratio, 4.86; 95% confidence interval, 1.25–18.91; p=0.022). @*Conclusions@#CoNS, including S. epidermidis, was the most common conjunctival bacterial flora, with a fluoroquinolone sensitivity rate ranging from 58.5% to 69.8% in patients undergoing ophthalmic procedures. Statin use was a significant risk factor for fluoroquinolone resistance.

Twenty-Five Year Trend Change in the Etiology of Pediatric Invasive Bacterial Infections in Korea, 1996–2020

Background@#The coronavirus disease-2019 (COVID-19) pandemic has contributed to the change in the epidemiology of many infectious diseases. This study aimed to establish the pre-pandemic epidemiology of pediatric invasive bacterial infection (IBI). @*Methods@#A retrospective multicenter-based surveillance for pediatric IBIs has been maintained from 1996 to 2020 in Korea. IBIs caused by eight bacteria (Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis, Staphylococcus aureus, Streptococcus agalactiae, Streptococcus pyogenes, Listeria monocytogenes, and Salmonella species) in immunocompetent children > 3 months of age were collected at 29 centers. The annual trend in the proportion of IBIs by each pathogen was analyzed. @*Results@#A total of 2,195 episodes were identified during the 25-year period between 1996 and 2020. S. pneumoniae (42.4%), S. aureus (22.1%), and Salmonella species (21.0%) were common in children 3 to 59 months of age. In children ≥ 5 years of age, S. aureus (58.1%), followed by Salmonella species (14.8%) and S. pneumoniae (12.2%) were common. Excluding the year 2020, there was a trend toward a decrease in the relative proportions of S. pneumoniae (rs = −0.430, P = 0.036), H. influenzae (rs = −0.922, P 3 months of age. These findings can be used as the baseline data to navigate the trend in the epidemiology of pediatric IBI in the post COVID-19 era.

Machine Learning Algorithms for the Prediction of Locomotor Activity by an Infrared Motion Detector on the Sleep-wake States in Mice

Objective@#Even though studies using machine learning on sleep-wake states have been performed, studies in various conditions are still necessary. This study aimed to examine the performance of the prediction model of locomotor activities on sleep-wake states using machine learning algorithms. @*Methods@#The processed data using moving average of locomotor activities were used as predicting features. The sleep-wake states were used as true labels. The prediction models were established by machine learning classifiers such as support vector machine with radial basis function (SVM-RBF), linear discriminant analysis (LDA), naïve Bayes, and random forest (RF). The prediction model was evaluated by a six-fold cross validation. @*Results@#The SVM-RBF and RF showed acceptable performance within a window of moving average from 480 to 1,200 seconds. The highest accuracy (0.869) was shown by the RF at the interval of 480 seconds. Meanwhile, the highest area under the curve (0.939) was shown by LDA at the interval of 870 seconds. @*Conclusion@#This study suggested that the prediction model on sleep-wake state using machine learning could show an improvement of the model performance when using moving average with raw data. The prediction model using locomotor activity can be useful in research on sleep-wake state.

Contact Investigations With a Single Tuberculin Skin Test on Infants Exposed to Tuberculosis in a Postpartum Care Center During the Neonatal Period

Background@#Tuberculosis (TB) exposure in congregate settings related to neonates is a serious medical and social issue. TB exposure happens during the neonatal period, but contact investigations for exposed infants are usually conducted after the neonatal period.Generally, recommendations for screening and managing close contact are different for neonates and children. Thus, there are challenges in contact investigations. We aimed to report contact investigations with a single tuberculin skin test (TST) on infants exposed to infectious TB in a postpartum care center. @*Methods@#The index case was a healthcare worker with active pulmonary TB: sputum acidfast bacilli smear negative, culture positive, and no cavitary lesion. All exposed infants underwent medical examinations and chest X-ray. After TB disease was ruled out, contacts received window period prophylaxis with isoniazid (INH) until three months after the last exposure. TST was performed only once after completing the prophylaxis. @*Results@#A total of 288 infants were selected as high-priority contacts. At the initial contact investigation, the age of infants ranged from 8 to 114 days. None of these exposed infants had TB disease. The prevalence of latent TB infection (LTBI) was 25.3% (73/288; 95% confidence interval [CI], 20.7–30.7). There were no serious adverse events related to the window period prophylaxis or LTBI treatment with INH. During the 1-year follow-up period, no infants progressed to overt TB disease. The size of TST induration in infants vaccinated with percutaneous Bacillus Calmette-Guérin (BCG) vaccine was significantly larger than that of infants vaccinated with intradermal BCG vaccine (median, 8 mm vs. 5 mm; P = 0.002). In multiple logistic regression analysis, independent factors associated with TST positivity (≥ 10 mm induration) were male (adjusted odds ratio [aOR], 2.98; 95% CI, 1.6–5.64), percutaneous BCG vaccination (aOR, 3.30; 95% CI, 1.75–6.48), TST reading between 60 and 72 hours after injecting purified protein derivative (aOR, 2.87; 95% CI, 1.53–5.49), and INH prophylaxis more than four weeks (aOR, 0.49; 95% CI, 0.25–0.94). @*Conclusion@#A single TST at three months after the last TB exposure with INH prophylaxis could be used as a main protocol in contact investigations for infants exposed to infectious TB during the neonatal period in congregate settings in Korea.

How does quiz activity affect summative assessment outcomes? An analysis of three consecutive years’ data on self-directed learning / 고신대학교의과대학학술지

Background@#We investigated how quiz activities can improve summative assessment outcomes by analyzing the relationship between them. @*Methods@#We used 217 first-year medical students’ medical informatics data from 3 consecutive years. We analyzed summative assessment outcomes between quiz completion and incompletion groups, one-time and multiple-time quiz learning groups, and three combined comparisons between subgroups of quiz learning activity frequencies: 1 versus 2, 3, 4, and 6 (group 1), 1 and 2 versus 3, 4, and 6 (group 2), and 1, 2, and 3 versus 4 and 6 (group 3). We then analyzed correlations between the final quiz scores and summative assessment outcomes. @*Results@#The summative assessment means for students who completed quizzes and those who did not were 87.16±8.73 and 83.22±8.31, respectively (p=0.001). The means for the one-time and multiple-time quiz learning groups were 86.54±8.94 and 88.71±8.10, respectively (p=0.223). The means for combined subgroups were not significantly different between groups (p>0.05), although a statistically significant increasing trend was found from groups 1 to 3 (0.223>0.203>0.075 using the t-test and 0.225>0.150>0.067 using the Mann-Whitney test, respectively). Summative assessment scores were not significantly correlated with quiz scores (r=0.115, p=0.213). @*Conclusions@#Quizzes helped students who used self-directed learning obtain better summative assessment outcomes. Formative quizzes presumably did not provide students with direct knowledge, but showed them their weak points and motivated them to work on areas where their knowledge was insufficient.

Optimization of Analysis of Circadian Rest-Activity Rhythm Using Cosinor Analysis in Mice

Objective@#Data processing in analysis of circadian rhythm was performed in various ways. However, there was a lack of evidence for the optimal analysis of circadian rest-activity rhythm. Therefore, we aimed to perform mathematical simulations of data processing to investigate proper evidence for the optimal analysis of circadian rest-activity rhythm. @*Methods@#Locomotor activities of 20 ICR male mice were measured by infrared motion detectors. The data of locomotor activities was processed using data summation, data average, and data moving average methods for cosinor analysis. Circadian indices were estimated according to time block, respectively. Also, statistical F and p-values were calculated by zero-amplitude test. @*Results@#The data moving average result showed well-fitted cosine curves independent of data processing time. Meanwhile, the amplitude, MESOR, and acrophase were properly estimated within 800 seconds in data summation and data average methods. @*Conclusion@#These findings suggest that data moving average would be an optimal method for data processing in a cosinor analysis and data average within 800-second data processing time might be adaptable. The results of this study can be helpful to analyze circadian restactivity rhythms and integrate the results of the studies using different data processing methods.

Prediction of Locomotor Activity by Infrared Motion Detector on Sleep-wake State in Mice

Objective@#Behavioral assessments that effectively predict sleep-wake states were tried in animal research. This study aimed to examine the prediction power of an infrared locomotion detector on the sleep-wake states in ICR (Institute Cancer Research) mice. We also explored the influence of the durations and ways of data processing on the prediction power. @*Methods@#The locomotor activities of seven male mice in home cages were recorded by infrared detectors. Their sleep-wake states were assessed by video analysis. Using the receiver operating characteristic curve analysis, the cut-off score was determined, then the area under the curve (AUC) values of the infrared motion detector that predicted sleep-wake states were calculated. In order to improve the prediction power, the four ways of data processing on the prediction power were performed by Matlab 2013b. @*Results@#In the initial analysis of raw data, the AUC value was 0.785, but it gradually reached to 0.942 after data summation. The simple data averaging and summation among four different methods showed the maximal AUC value. The 10-minute data summation improved sensitivity (0.889) and specificity (0.901) significantly from the baseline value (sensitivity 0.615; specificity 0.936) (p ＜ 0.001). @*Conclusion@#This study suggests that the locomotor activity measured by an infrared motion detector might be useful to predict the sleep-wake states in ICR mice. It also revealed that only simple data summation may improve the predictive power. Using daily locomotor activities measured by an infrared motion detector is expected to facilitate animal research related to sleep-wake states.

Adverse Events Following Immunization Associated with Coronavirus Disease 2019 Vaccination Reported in the Mobile Vaccine Adverse Events Reporting System

Background@#Vaccination against coronavirus disease 2019 (COVID-19) is underway globally to prevent the infection caused by the severe acute respiratory syndrome coronavirus 2. We aimed to investigate the adverse events following immunization (AEFIs) for COVID-19 among healthcare workers (HCWs). @*Methods@#This was a retrospective study of the AEFIs associated with the first dose of the ChAdOx1 nCoV-19 vaccine at the Kosin University Gospel Hospital from March 3 to March 22, 2021. We investigated the systemic and local adverse events during the 7 days following the vaccination using the Mobile Vaccine Adverse Events Reporting System (MVAERS) developed by our hospital. @*Results@#A total of 1,503 HCWs were vaccinated, and the data of 994 HCWs were reported in the MVAERS. The most commonly reported AEFIs were tenderness at the injection site (94.5%), fatigue (92.9%), pain at the injection site (88.0%), and malaise (83.8%). The severity of most AEFIs was mild-to-moderate, and the severity and number of AEFIs were less in the older age group. There were no serious events requiring hospitalization, and most AEFIs improved within a few days. @*Conclusion@#The AEFIs associated with the ChAdOx1 nCoV-19 vaccine were tolerable, and the use of the MVAERS was helpful in monitoring the AEFIs. The use of MVAERS will help in sharing accurate and ample information about vaccination against COVID-19.

Prediction of Locomotor Activity by Infrared Motion Detector on Sleep-wake State in Mice

Objective@#Behavioral assessments that effectively predict sleep-wake states were tried in animal research. This study aimed to examine the prediction power of an infrared locomotion detector on the sleep-wake states in ICR (Institute Cancer Research) mice. We also explored the influence of the durations and ways of data processing on the prediction power. @*Methods@#The locomotor activities of seven male mice in home cages were recorded by infrared detectors. Their sleep-wake states were assessed by video analysis. Using the receiver operating characteristic curve analysis, the cut-off score was determined, then the area under the curve (AUC) values of the infrared motion detector that predicted sleep-wake states were calculated. In order to improve the prediction power, the four ways of data processing on the prediction power were performed by Matlab 2013b. @*Results@#In the initial analysis of raw data, the AUC value was 0.785, but it gradually reached to 0.942 after data summation. The simple data averaging and summation among four different methods showed the maximal AUC value. The 10-minute data summation improved sensitivity (0.889) and specificity (0.901) significantly from the baseline value (sensitivity 0.615; specificity 0.936) (p ＜ 0.001). @*Conclusion@#This study suggests that the locomotor activity measured by an infrared motion detector might be useful to predict the sleep-wake states in ICR mice. It also revealed that only simple data summation may improve the predictive power. Using daily locomotor activities measured by an infrared motion detector is expected to facilitate animal research related to sleep-wake states.

Adverse Events Following Immunization Associated with Coronavirus Disease 2019 Vaccination Reported in the Mobile Vaccine Adverse Events Reporting System

Background@#Vaccination against coronavirus disease 2019 (COVID-19) is underway globally to prevent the infection caused by the severe acute respiratory syndrome coronavirus 2. We aimed to investigate the adverse events following immunization (AEFIs) for COVID-19 among healthcare workers (HCWs). @*Methods@#This was a retrospective study of the AEFIs associated with the first dose of the ChAdOx1 nCoV-19 vaccine at the Kosin University Gospel Hospital from March 3 to March 22, 2021. We investigated the systemic and local adverse events during the 7 days following the vaccination using the Mobile Vaccine Adverse Events Reporting System (MVAERS) developed by our hospital. @*Results@#A total of 1,503 HCWs were vaccinated, and the data of 994 HCWs were reported in the MVAERS. The most commonly reported AEFIs were tenderness at the injection site (94.5%), fatigue (92.9%), pain at the injection site (88.0%), and malaise (83.8%). The severity of most AEFIs was mild-to-moderate, and the severity and number of AEFIs were less in the older age group. There were no serious events requiring hospitalization, and most AEFIs improved within a few days. @*Conclusion@#The AEFIs associated with the ChAdOx1 nCoV-19 vaccine were tolerable, and the use of the MVAERS was helpful in monitoring the AEFIs. The use of MVAERS will help in sharing accurate and ample information about vaccination against COVID-19.

Research Areas and Trends in Articles on Pediatric and Adolescent Tuberculosis in Korea

PURPOSE: Despite the decline in tuberculosis (TB) incidence and mortality rates in the Republic of Korea through a national TB control program, TB remains one of the most critical infectious diseases in Korean children. We investigated the trends and research areas of published articles on TB in Korean children and adolescents. METHODS: In 6 Korean and overseas databases, we searched titles and abstracts including “tuberculo*” or “TB,” “child*” or “adolescen*” or “neonat*” or “infant*” or “pediatric*,” and “korea*.” The publication type, publication year, research areas, journal title, and research subjects were analyzed. RESULTS: Out of the 257 searched documents, 120 papers were included in the analysis. Of these, 82 were original articles (68.3%), 33 case reports (27.5%), 4 review articles (3.3%), and 1 guideline (0.8%). In the original articles, the most common subject of studies was the clinical characteristics of patients with TB (36.6%), followed by diagnostics (29.3%), contact investigations (9.8%), epidemiology (6.1%), treatment (4.9%), vaccine (3.6%), latent TB infection (3.6%), complications (3.6%), and surveys on perception of TB (2.4%). From 1962, 4 articles were published in the 1960s, 10 articles in the 1970s, 11 articles in the 1980s, 22 articles in the 1990s, 26 articles in the 2000s, and 47 articles since 2010. CONCLUSIONS: The amount of research on TB in Korean children has increased over the past 5 decades; however, it has mainly focused on the clinical characteristics and diagnostics. Research in different areas, such as treatment and vaccine, is needed in the future.

Erratum: Addition of a Co-Author: Etiology of Invasive Bacterial Infections in Immunocompetent Children in Korea (2006–2010): a Retrospective Multicenter Study

The authors regret that one co-author (Kyung-Hyo Kim) was missing in the article.

A Multicenter Survey on the Current Status of Pediatric Blood Cultures in Korea

PURPOSE: Blood culture is an essential diagnostic tool and requires clear indications, proper techniques, and quality control. We aimed to investigate whether blood cultures in children are appropriate for indications, are performed correctly, and receive proper quality control. METHODS: We conducted an online survey targeting pediatric infectious diseases (ID) specialists working in general hospitals and neonatologists (Neo) working at hospitals operating a neonatal intensive care unit in Korea. RESULTS: Approximately 81.1% (30/37) of pediatric ID specialists and 72.2% (52/72) of Neo responded to the survey. Some of the respondents (33.3% of ID and 59.6% of Neo) performed blood culture as a regular test irrespective of the indication. Approximately 40% of ID and 65.4% of Neo ordered only one set of blood culture in patients suspected with bacteremia. The most commonly used disinfectant for skin preparation was povidone-iodine, while the skin preparation method varied by institution. Approximately two-thirds of the institutions were monitoring the blood culture contamination rate, whereas relatively few provided staff with feedback on that rate. In addition, less than half of the institutions were providing regular staff training on blood culture (40% of ID and 28.8% of Neo). CONCLUSIONS: The indication and methods of blood culture for children varied according to institution, and few hospitals exert effort in improving the quality of blood culture. Institutions have to strive constantly toward improvement of blood culture quality and evidence-based recommendations for pediatric blood cultures should be standardized.

Empirical antibiotics for recurrent urinary tract infections in children / 고신대학교의과대학학술지

OBJECTIVES: The purpose of this study was to compare antibiotic resistance patterns between first urinary tract infection (UTI) and recurrent UTI groups and to obtain information regarding empirical antibiotic selection for treating recurrent UTI. METHODS: We retrospectively reviewed 148 children treated for UTIs from January 2009 to June 2016. The patients were divided into two groups: first UTI (N = 148) and recurrent UTI (17 patients and 20 episodes). RESULTS: In both groups, Escherichia coli was the most frequent causative organism, accounting for 89.9% and 75.0% in the first and recurrent UTI groups, respectively. When E. coli or Klebsiella pneumoniae was the causative organism, extended-spectrum β-lactamase (ESBL)-producing organisms were more frequent in the recurrent UTI group (17.6%) than in the first UTI group (14.0%); however, this difference was not statistically significant (P = 0.684). Cefotaxime was the most frequently used first-line empirical antibiotic in both groups. In the first UTI and recurrent UTI groups, 7.4% and 15.0% of patients were treated with intravenous antibiotics as definitive therapy, respectively (P = 0.250). Fifteen out of 17 patients having a second UTI had different causative organisms or antibiotic susceptibility patterns compared to their previous episode. CONCLUSIONS: Escherichia coli was the most frequent causative organism in the recurrent UTI group. There were no differences in the proportion of ESBL-producing organisms between the first UTI and recurrent UTI groups. Therefore, when a UTI recurs in children, the antibiotics effective on the most common causative organism might be administered as empirical antibiotics.

Etiology of Invasive Bacterial Infections in Immunocompetent Children in Korea (2006–2010): a Retrospective Multicenter Study

BACKGROUND: Invasive bacterial infections in apparently immunocompetent children were retrospectively analyzed to figure causative bacterial organisms in Korea. METHODS: A total of 947 cases from 25 university hospitals were identified from 2006 to 2010 as a continuance of a previous 10-year period study from 1996 to 2005. RESULTS: Escherichia coli (41.3%), Streptococcus agalactiae (27.7%), and Staphylococcus aureus (27.1%) were the most common pathogens in infants < 3 months of age. S. agalactiae was the most prevalent cause of meningitis and pneumonia and E. coli was the major cause of bacteremia without localizing signs in this group. In children 3 to 59 months of age, Streptococcus pneumoniae (54.2%), S. aureus (20.5%), and Salmonella spp. (14.4%) were the most common pathogens. S. pneumoniae was the leading cause of pneumonia (86.0%), meningitis (65.0%), and bacteremia without localizing signs (49.0%) in this group. In children ≥ 5 years of age, S. aureus (62.8%) was the predominant pathogen, followed by Salmonella species (12.4%) and S. pneumoniae (11.5%). Salmonella species (43.0%) was the most common cause of bacteremia without localizing signs in this group. The relative proportion of S. aureus increased significantly over the 15-year period (1996–2010) in children ≥ 3 months of age (P < 0.001), while that of Haemophilus influenzae decreased significantly in both < 3 months of age group (P = 0.036) and ≥ 3 months of age groups (P < 0.001). CONCLUSION: S. agalactiae, E. coli, S. pneumoniae, and S. aureus are common etiologic agents of invasive bacterial infections in Korean children.

Erratum: A Retrospective Analysis of Use in Hospitalized Children with Upper Respiratory Tract Infection

The authors found an error in the title. Th etitle has been updated from “A Retrospective Analysis of Use in Hospitalized Children with Upper Respiratory Tract Infection” to “A Retrospective Analysis of Antibiotic Use in Hospitalized Children with Upper Respiratory Tract Infection.”

Infectious Pseudoaneurysm Caused by Group A Streptococcus in a Child without Underlying Disease

Group A streptococcus is a common cause of upper respiratory infection in children; however, it is a rare cause of pseudoaneurysm in pediatrics with only limited reports of cases associated with cardiac surgery and underlying disease. We report a case of infectious pseudoaneurysm of the right internal iliac artery caused by group A streptococcus in a previously healthy 5-year-old boy who presented with scarlet fever and group A streptococcal bacteremia. He was admitted to the hospital with fever, rash on the whole body, and sore throat, accompanied by severe leg pain. He was treated with surgical removal and antibiotics. Because a pseudoaneurysm may develop in children without vascularrelated underlying diseases, we should consider the possibility of this important clinical diagnosis in patients with scarlet fever.

Erratum: A Retrospective Analysis of Use in Hospitalized Children with Upper Respiratory Tract Infection

The authors found an error in the title. Th etitle has been updated from “A Retrospective Analysis of Use in Hospitalized Children with Upper Respiratory Tract Infection” to “A Retrospective Analysis of Antibiotic Use in Hospitalized Children with Upper Respiratory Tract Infection.”

Infectious Pseudoaneurysm Caused by Group A Streptococcus in a Child without Underlying Disease

Group A streptococcus is a common cause of upper respiratory infection in children; however, it is a rare cause of pseudoaneurysm in pediatrics with only limited reports of cases associated with cardiac surgery and underlying disease. We report a case of infectious pseudoaneurysm of the right internal iliac artery caused by group A streptococcus in a previously healthy 5-year-old boy who presented with scarlet fever and group A streptococcal bacteremia. He was admitted to the hospital with fever, rash on the whole body, and sore throat, accompanied by severe leg pain. He was treated with surgical removal and antibiotics. Because a pseudoaneurysm may develop in children without vascularrelated underlying diseases, we should consider the possibility of this important clinical diagnosis in patients with scarlet fever.