Usefulness of a new polyvinyl alcohol hydrogel (PVA-H)-based simulator for endoscopic submucosal dissection training: a pilot study

Background/Aims@#We developed a new endoscopic submucosal dissection (ESD) simulator and evaluated its efficacy and realism for use training endoscopists. @*Methods@#An ESD simulator was constructed using polyvinyl alcohol hydrogel sheets and compared to a previous ESD simulator. Between March 1, 2020, and December 30, 2021, eight expert endoscopists from three different centers analyzed the procedure-related factors of the simulator. Five trainees performed gastric ESD exercises under the guidance of these experts. @*Results@#Although the two ESD simulators provided overall favorable outcomes in terms of ESD-related factors, the new simulator had several benefits, including better marking of the target lesion’s limits (p<0.001) and overall handling (p<0.001). Trainees tested the usefulness of the new ESD simulator. The complete resection rate improved after 3 ESD training sessions (9 procedures), and the perforation rate decreased after 4 sessions (12 procedures). @*Conclusions@#We have developed a new ESD simulator that can help beginners achieve a high level of technical experience before performing real-time ESD procedures in patients.

Osteoporosis Is Associated with an Increased Risk of Colorectal Adenoma and High-Risk Adenoma: A Retrospective, Multicenter, Cross-Sectional, Case-Control Study

Background/Aims@#The protective effects of vitamin D and calcium on colorectal neoplasms are known. Bone mineral density (BMD) may be a reliable biomarker that reflects the long-term anticancer effect of vitamin D and calcium. This study aimed to evaluate the association between BMD and colorectal adenomas including high-risk adenoma. @*Methods@#A multicenter, cross-sectional, case-control study was conducted among participants with average risk of colorectal cancer who underwent BMD and screening colonoscopy between 2015 and 2019. The main outcome was the detection of colorectal neoplasms. The variable under consideration was low BMD (osteopenia/osteoporosis). The logistic regression model included baseline demographics, components of metabolic syndrome, fatty liver disease status, and aspirin and multivitamin use. @*Results@#A total of 2,109 subjects were enrolled. The mean age was 52.1±10.8 years and 42.6% were male. The adenoma detection rate was 43%. Colorectal adenoma and high-risk adenoma were both more prevalent in subjects with low BMD than those with normal BMD (48.2% vs 38.8% and 12.1% vs 9.1%). In the univariate analysis, old age, male sex, smoking, metabolic components, fatty liver, and osteoporosis were significantly associated with the risk of adenoma and high-risk adenoma. In the multivariate analysis, osteoporosis was independently associated with risk of colorectal adenoma (odds ratio [OR], 1.65; 95% confidence interval [CI], 1.11 to 2.46; p=0.014) and high-risk adenoma (OR, 1.94; 95% CI, 1.14 to 3.29; p=0.014). @*Conclusions@#Osteoporosis is an independent risk factor of colorectal adenoma and high-risk adenoma

Expression of Chemokine CCL28 in Ulcerative Colitis Patients

Background/Aims@#Ulcerative colitis (UC) is an inflammatory bowel disease for which new serological markers are required. The purpose of this study was to assess the role of the mucosaassociated epithelial chemokine CCL28 in UC. @*Methods@#The study included 50 patients; of these, 25 were patients with UC, and 25 were healthy controls. The levels of serum CCL28 were analyzed using enzyme-linked immunosorbent assay. CCL28 expression was analyzed by immunohistochemistry (IHC) in 15 representative colon tissues biopsied based on disease activity (UC patients with severe activity, five samples;UC patients with mild activity, five samples; healthy controls, five samples). @*Results@#The serum CCL28 levels were remarkably higher (p<0.05) in patients with UC (median, 235.7 pg/mL; IQR, 63.8 to 117.2 pg/mL) than in healthy controls (median, 48.9, pg/mL; IQR, 35.9 to 42.0 pg/mL). However, there was no significant difference in serum CCL28 according to disease extent or activity. In contrast, IHC analysis revealed a significant difference in CCL28 consistent with disease status, disease extent, and disease activity. @*Conclusions@#CCL28 could be useful for diagnosing UC. However, further validations of CCL28 on disease activity and severity are needed.

Orostachys japonicus ethyl acetate fraction suppresses MRSA biofilm formation

To investigate the effect of Orostachys (O.) japonicus, a perennial herbaceous plant of the Family Crassulaceae, on biofilm formed by methicillin-resistant Staphylococcus aureus (MRSA). Methods: Powdered O. japonicus was extracted by 95% methanol, concentrated, and then, systematically fractionated with n-heane, dichloromethane (DCM), ethyl acetate (EtOAc), n-butanol, and H2O according to polarity. Among them, the flavonoid-rich EtOAc fraction demonstrated the highest antibacterial activity and was used in this study. Using the biofilm inhibition assay, cell-surface attachment assay, confocal laser scanning microscopy, latex agglutination assay, and real time qRT-PCR, we examined whether the EtOAc fraction inhibited the formation of MRSA biofilm. Results: The EtOAc fraction exhibited distinct activity against biofilm formation and cell-surface attachment of MRSA up to 1 mg/mL through down-regulating the expression of mecA gene and the production and agglutination of penicillin-binding protein 2a as solidly observed in biofilm inhibition assay, cell-suface attachment assay, confocal laser scanning microscopy, latex agglutination assay, and real time qRT-PCR analysis. Conclusions: These results suggest that O. japonicus could be utilized as a potential resource for the development of new antibiofilm formation of MRSA and antibacterial agents in the future.

Synaptic loss and amyloid beta alterations in the rodent hippocampus induced by streptozotocin injection into the cisterna magna / 한국실험동물학회지

To date, researchers have developed various animal models of Alzheimer’s disease (AD) to investigate its mechanisms and to identify potential therapeutic treatments. A widely recognized model that mimics the pathology of human sporadic AD involves intracerebroventricular (ICV) injection with streptozotocin (STZ). However, ICV injections are an invasive approach, which creates limitations in generalizing the results. In this study, we produced a rodent model of AD using STZ (3 mg/kg) injection via the cisterna magna (CM) once every week for 4 weeks, and analyzed at 4 weeks and 16 weeks after final injection. In the CM-STZ rodent model of AD, we observed increase in extracellular amyloid-beta (Aβ) deposition and decrease and abnormal morphology of post-synaptic protein, PSD95 in 16 weeks STZ-injected group. The model developed using our less-invasive method induced features of AD-like pathology, including significantly increased extracellular amyloid-beta deposition, and decreased synaptic protein in the hippocampus. These findings supporting the success of this alternative approach, and thus, we suggest this is a promising, less invasive model for use in future AD research.

Impaired Hand Dexterity Function in a Non-human Primate Model with Chronic Parkinson’s Disease

ymptoms of Parkinson’s disease (PD) caused by loss of dopaminergic neurons are accompanied by movement disorders, including tremors, rigidity, bradykinesia, and akinesia. Non-human primate (NHP) models with PD play an essential role in the analysis of PD pathophysiology and behavior symptoms. As impairments of hand dexterity function can affect activities of daily living in patients with PD, research on hand dexterity function in NHP models with chronic PD is essential. Traditional rating scales previously used in the evaluation of animal spontaneous behavior were insufficient due to factors related to subjectivity and passivity. Thus, experimentally designed applications for an appropriate apparatus are necessary. In this study, we aimed to longitudinally assess hand dexterity function using hand dexterity task (HDT) in NHP-PD models. To validate this assessment, we analyzed the alteration in Parkinsonian tremor signs and the functionality of presynaptic dopaminergic neuron using positron emission tomography imaging of dopamine transporters in these models. In addition, a significant inverse correlation between HDT and DAT level was identified, but no local bias was found. The correlation with intention tremor signs was lower than the resting tremor. In conclusion, the evaluation of HDT may reflect behavioral symptoms of NHP-PD models. Furthermore, HDT was effectively used to experimentally distinguish intention tremors from other tremors.

Clinical Characteristics and Mortality Predictors of COVID-19 Patients Hospitalized at Nationally-Designated Treatment Hospitals

Background@#Coronavirus disease 2019 (COVID-19) was first reported in December 2019 in China, and then it has disseminated worldwide. In Korea, a religious group-related super-spreading event triggered a sudden outbreak in Daegu city and Gyeongsangbuk-do in southeast Korea. This study was undertaken to document the clinical characteristics of patients hospitalized in Gyeongsangbuk-do. @*Methods@#Three hundred and fifty-two patients with confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection hospitalized at Dongguk University Gyeongju Hospital or at the Andong Medical Center between February 18th and June 30th were enrolled in this study. Medical records were reviewed and demographic and clinical features, including comorbidities, symptoms, radiological and laboratory findings on admission were analyzed. In addition, we sought to identify risk factors of mortality. @*Results@#Mean age of the 352 study subjects was 56 years (range, 14–95). The mortality rate was 6.8% and mean age at death was 81 years (range, 57–91). The most common symptom was cough (31.8%) followed by a febrile sensation (28.4%), sputum (17.0%), sore throat (15.6%), and myalgia (13.1%). Eighty-one (23.0%) patients were asymptomatic, but a half of these patients exhibited pneumonic infiltration at presentation. Chest radiology showed no active lesion in 41.8% of the study subjects, bilateral pneumonia in 46.9%, and unilateral pneumonic infiltration in 11.4%. Among 24 patients that died, 18 subjects were transferred from a care facility. An age of ≥ 70 years, previous history of malignancy or diabetes, and fever (≥ 37.5°C) on admission were found to be significant risk factors of mortality. @*Conclusion@#Patients aged ≥ 70 years, those with fever on admission, and patients with an underlying malignancy or diabetes were found to be more likely to succumb to COVID-19.Elderly in care facilities or hospitalized patients with an underlying disease should receive more attention and be considered for preventive quarantine.

Analysis of Prognosis according to Type of Health Insurance in Five Major Gastrointestinal Cancer Patients in Public Hospitals: Single-institution Retrospective Study / 대한소화기학회지

BACKGROUND/AIMS: Public hospitals were established to provide high quality medical services to low socioeconomic status patients. This study examined the effects of public hospitals on the treatment and prognosis of patients with five-major gastrointestinal (GI) cancers (stomach cancer, colon cancer, liver cancer, bile duct cancer, and pancreatic cancer).METHODS: Among the 1,268 patients treated at Seoul National University Boramae Medical Center from January 2010 to December 2017, 164 (13%) were in the medicare group. The data were analyzed to identify and compare the clinical manifestations, treatment modality, and clinical outcomes between the groups.RESULTS: No statistically significant differences in the clinical data (age, sex), treatment method, and five-year survival rate were observed between the health insurance group and medicare group in the five major GI cancer patients. On the other hand, some medicare group patients tended more comorbidities and fewer treatment options than health insurance patients.CONCLUSIONS: Public hospitals have a positive effect on the treatment and prognosis in medicare group patients with the five-major GI cancers.

A Newly Designed 3-Dimensional Printer-Based Gastric Hemostasis Simulator with Two Modules for Endoscopic Trainees (with Video)

BACKGROUND/AIMS: We used 3-dimensional (3D) printing technology to create a new hemostasis simulator for the stomach and investigated its efficacy and realism in endoscopic hemostasis training. METHODS: A new stomach hemostasis simulator, with two hemostasis modules for hemoclipping and injection, was constructed using a 3D printer. Twenty-one endoscopists, including 11 first-year fellows (beginner group) and 10 faculty members (expert group), tested the performance of the simulator. We recorded and reviewed five training sessions and evaluated the simulator with questionnaires using a 7-point Likert scale. RESULTS: The mean evaluation score of the expert group was 6.3±0.5 for the hemoclipping module and 6.0±0.6 for the injection module. The expert group strongly agreed that endoscopic handling in the simulator was realistic and reasonable for hemostasis training. The mean procedure time for hemoclipping was 72.7±7.1 seconds for the beginner group and 19.7±1.2 seconds for the expert group. The mean procedure time for injection was 92.1±9.8 seconds for the beginner group and 36.3±2 seconds for the expert group. The procedure time of beginner group became shorter with repetition and was significantly lower by the fifth trial. CONCLUSIONS: A new 3D-printed hemostasis simulator is capable of hemostasis training and can very effectively train beginners before they perform the procedure in patients with gastrointestinal bleeding.

Abnormal Mitochondria in a Non-human Primate Model of MPTP-induced Parkinson's Disease: Drp1 and CDK5/p25 Signaling

Mitochondria continuously fuse and divide to maintain homeostasis. An impairment in the balance between the fusion and fission processes can trigger mitochondrial dysfunction. Accumulating evidence suggests that mitochondrial dysfunction is related to neurodegenerative diseases such as Parkinson's disease (PD), with excessive mitochondrial fission in dopaminergic neurons being one of the pathological mechanisms of PD. Here, we investigated the balance between mitochondrial fusion and fission in the substantia nigra of a non-human primate model of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD. We found that MPTP induced shorter and abnormally distributed mitochondria. This phenomenon was accompanied by the activation of dynamin-related protein 1 (Drp1), a mitochondrial fission protein, through increased phosphorylation at S616. Thereafter, we assessed for activation of the components of the cyclin-dependent kinase 5 (CDK5) and extracellular signal-regulated kinase (ERK) signaling cascades, which are known regulators of Drp1(S616) phosphorylation. MPTP induced an increase in p25 and p35, which are required for CDK5 activation. Together, these findings suggest that the phosphorylation of Drp1(S616) by CDK5 is involved in mitochondrial fission in the substantia nigra of a non-human primate model of MPTP-induced PD.

Technical Feasibility of a Guidetube for Various Endoscopic Procedures in Human Gastrointestinal Simulators

BACKGROUND/AIMS: Many gastrointestinal (GI) endoscopic procedures are difficult and cumbersome owing to the limitation of currently available endoscopic devices. This study aimed to develop an endoscopic guidetube for multipurpose endoscopic procedures and assess its use in a realistic GI endoscopic simulator. METHODS: The guidetube used is a soft overtube composed of neoprene and is designed to assist various endoscopic procedures on demand. In total, 15 types of procedures were performed in GI simulators. Four procedures were performed in the stomach model and 11 in the colon model. The procedures include repeated endoscopic insertion and foreign body removal in various positions. The mean insertion and procedure time were assessed in each session. All procedures were performed by 5 expert endoscopists. RESULTS: Endoscopic procedures with the new guidetube were faster and more effective than the conventional endoscopic techniques. The mean insertion time of the endoscope with the guidetube was significantly shorter than that without the guidetube. The guidetube was safely inserted without scratch using low pushing force. Objects of various sizes larger than the endoscopic channel were easily removed by the guidetube-assisted endoscopic procedures. CONCLUSIONS: This preliminary study shows that guidetube-assisted endoscopic procedures are faster, easier, safer and cheaper than conventional endoscopic procedures.

Does any specific infection cause Kawasaki disease? / 소아과

No abstract available.

Ergonovine Stress Echocardiography for the Diagnosis of Vasospastic Angina and Its Prognostic Implications in 3,094 Consecutive Patients

BACKGROUND AND OBJECTIVES@#Ergonovine stress echocardiography (ErgECHO) has been proposed as a noninvasive tool for the diagnosis of coronary vasospasm. However, concern over the safety of ErgECHO remains. This study was undertaken to investigate the safety and prognostic value of ErgECHO in a large population.@*METHODS@#We studied 3,094 consecutive patients from a single-center registry who underwent ErgECHO from November 2002 to June 2009. Medical records, echocardiographic data, and laboratory findings obtained from follow-up periods were analyzed.@*RESULTS@#The overall positive rate of ErgECHO was 8.6%. No procedure-related mortality or myocardial infarction (MI) occurred. Nineteen patients (0.6%) had transient symptomatic complications during ErgECHO including one who was successfully resuscitated. Cumulative major adverse cardiac events (MACEs) occurred in 14.0% and 5.1% of the patients with positive and negative ErgECHO results, respectively (p 220 mg/dL, and positive ErgECHO result itself were independent factors associated with MACEs.@*CONCLUSIONS@#ErgECHO can be performed safely by experienced physicians and its positive result may be an independent risk factor for long-term adverse outcomes. It may also be an alternative tool to invasive ergonovine-provoked coronary angiography for the diagnosis of vasospastic angina.

Protective Effect of Right Ventricular Mitochondrial Damage by Cyclosporine A in Monocrotaline-induced Pulmonary Hypertension

BACKGROUND AND OBJECTIVES@#Mitochondria play a key role in the pathophysiology of heart failure and mitochondrial permeability transition pore (MPTP) play a critical role in cell death and a critical target for cardioprotection. The aim of this study was to evaluate the protective effects of cyclosporine A (CsA), one of MPTP blockers, and morphological changes of mitochondria and MPTP related proteins in monocrotaline (MCT) induced pulmonary arterial hypertension (PAH).@*METHODS@#Eight weeks old Sprague-Dawley rats were randomized to control, MCT (60 mg/kg) and MCT plus CsA (10 mg/kg/day) treatment groups. Four weeks later, right ventricular hypertrophy (RVH) and morphological changes of right ventricle (RV) were done. Western blot and reverse transcription polymerase chain reaction (RT-PCR) for MPTP related protein were performed.@*RESULTS@#In electron microscopy, CsA treatment prevented MCT-induced mitochondrial disruption of RV. RVH was significantly increased in MCT group compared to that of the controls but RVH was more increased with CsA treatment. Thickened medial wall thickness of pulmonary arteriole in PAH was not changed after CsA treatment. In western blot, caspase-3 was significantly increased in MCT group, and was attenuated in CsA treatment. There were no significant differences in voltage-dependent anion channel, adenine nucleotide translocator 1 and cyclophilin D expression in western blot and RT-PCR between the 3 groups.@*CONCLUSIONS@#CsA reduces MCT induced RV mitochondrial damage. Although, MPTP blocking does not reverse pulmonary pathology, it may reduce RV dysfunction in PAH. The results suggest that it could serve as an adjunctive therapy to PAH treatment.

Anti-cancer effect of ethylacetate fraction from Orostachys japonicus on HT-29 human colon cancer cells by induction of apoptosis through caspase-dependent signaling pathway

Objective:To investigate the anti-colon cancer effects of ethylacetate fraction from Orostachys japonicus (O. japonicus) on HT-29 cancer cells.Methods:The viability of HT-29 cells was assayed by the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) method. Apoptosis induction and cell cycle inhibition were confirmed by fluorescein isothiocyanate and propidium iodide staining using flow cytometry. Morphological changes in the nucleus were observed, using a fluorescence microscope with 4′,6-diamidino-2-phenylindole (DAPI) nuclear staining. The expression levels of the upstream and downstream proteins involved in the anti-cancer mechanism were confirmed by Western blotting.Results:After treating HT-29 cells with different concentrations of ethylacetate fraction from O. japonicus, the viability of cells decreased in a concentration-dependent manner, while apoptosis induction and apoptotic body formation increased. Cell cycle analysis showed that the arrest occurred at the sub-GConclusions:Combining the above results, it is thought that the survival of HT-29 cells is suppressed by ethylacetate fraction from O. japonicus through mitochondrial regulation-induced caspase cascade activation, induction of apoptosis and cell cycle arrest.

Protective Effect of Right Ventricular Mitochondrial Damage by Cyclosporine A in Monocrotaline-induced Pulmonary Hypertension

BACKGROUND AND OBJECTIVES: Mitochondria play a key role in the pathophysiology of heart failure and mitochondrial permeability transition pore (MPTP) play a critical role in cell death and a critical target for cardioprotection. The aim of this study was to evaluate the protective effects of cyclosporine A (CsA), one of MPTP blockers, and morphological changes of mitochondria and MPTP related proteins in monocrotaline (MCT) induced pulmonary arterial hypertension (PAH). METHODS: Eight weeks old Sprague-Dawley rats were randomized to control, MCT (60 mg/kg) and MCT plus CsA (10 mg/kg/day) treatment groups. Four weeks later, right ventricular hypertrophy (RVH) and morphological changes of right ventricle (RV) were done. Western blot and reverse transcription polymerase chain reaction (RT-PCR) for MPTP related protein were performed. RESULTS: In electron microscopy, CsA treatment prevented MCT-induced mitochondrial disruption of RV. RVH was significantly increased in MCT group compared to that of the controls but RVH was more increased with CsA treatment. Thickened medial wall thickness of pulmonary arteriole in PAH was not changed after CsA treatment. In western blot, caspase-3 was significantly increased in MCT group, and was attenuated in CsA treatment. There were no significant differences in voltage-dependent anion channel, adenine nucleotide translocator 1 and cyclophilin D expression in western blot and RT-PCR between the 3 groups. CONCLUSIONS: CsA reduces MCT induced RV mitochondrial damage. Although, MPTP blocking does not reverse pulmonary pathology, it may reduce RV dysfunction in PAH. The results suggest that it could serve as an adjunctive therapy to PAH treatment.

Ergonovine Stress Echocardiography for the Diagnosis of Vasospastic Angina and Its Prognostic Implications in 3,094 Consecutive Patients

BACKGROUND AND OBJECTIVES: Ergonovine stress echocardiography (ErgECHO) has been proposed as a noninvasive tool for the diagnosis of coronary vasospasm. However, concern over the safety of ErgECHO remains. This study was undertaken to investigate the safety and prognostic value of ErgECHO in a large population. METHODS: We studied 3,094 consecutive patients from a single-center registry who underwent ErgECHO from November 2002 to June 2009. Medical records, echocardiographic data, and laboratory findings obtained from follow-up periods were analyzed. RESULTS: The overall positive rate of ErgECHO was 8.6%. No procedure-related mortality or myocardial infarction (MI) occurred. Nineteen patients (0.6%) had transient symptomatic complications during ErgECHO including one who was successfully resuscitated. Cumulative major adverse cardiac events (MACEs) occurred in 14.0% and 5.1% of the patients with positive and negative ErgECHO results, respectively (p 220 mg/dL, and positive ErgECHO result itself were independent factors associated with MACEs. CONCLUSIONS: ErgECHO can be performed safely by experienced physicians and its positive result may be an independent risk factor for long-term adverse outcomes. It may also be an alternative tool to invasive ergonovine-provoked coronary angiography for the diagnosis of vasospastic angina.

Anti-cancer effect of ethylacetate fraction from Orostachys japonicus on HT-29 human colon cancer cells by induction of apoptosis through caspase-dependent signaling pathway

Objective: To investigate the anti-colon cancer effects of ethylacetate fraction from Orostachys japonicus (O. japonicus) on HT-29 cancer cells. Methods: The viability of HT-29 cells was assayed by the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) method. Apoptosis induction and cell cycle inhibition were confirmed by fluorescein isothiocyanate and propidium iodide staining using flow cytometry. Morphological changes in the nucleus were observed, using a fluorescence microscope with 4′,6-diamidino-2-phenylindole (DAPI) nuclear staining. The expression levels of the upstream and downstream proteins involved in the anti-cancer mechanism were confirmed by Western blotting. Results: After treating HT-29 cells with different concentrations of ethylacetate fraction from O. japonicus, the viability of cells decreased in a concentration-dependent manner, while apoptosis induction and apoptotic body formation increased. Cell cycle analysis showed that the arrest occurred at the sub-G

Clinical Study of Prevalence of Antibiotic Resistance of Escherichia coli in Urinary Tract Infection in Children: A 9-year Retrospective, Single Center Experience

PURPOSE: The aim of this study was to determine the prevalence of antibiotic susceptibility and resistance of Escherichia coli in urinary tract infections (UTIs) in children. METHODS: We retrospectively reviewed the clinical records of 212 inpatients aged 18 years or younger with UTIs treated at the Pediatric Department of Dongguk University Gyeongju Hospital between January 2008 and December 2016. For comparison, patients were divided into three groups according to age as follows: group 1, ≤1 month; group 2, >1 month to ≤12 months; and group 3, ≥13 months. The antibiotic resistance rates from January 2008 to December 2012 (study period 1) and from January 2013 to December 2016 (study period 2) were analyzed statistically by group. RESULTS: As the patient age increased, the antibiotic resistance rate to ampicillin (P=0.013), levofloxacin (P=0.050), piperacillin/tazobactam (TZP) (P<0.001), and trimethoprim/sulfamethoxazole (P=0.002) increased. The frequency of extended spectrum beta-lactamase producing E. coli showed a significant difference from 5 cases (4.6%) in study period 1 and 16 cases (15.8%) in study period 2 (P=0.007). The antibiotic resistance rate of E. coli was compared between the two time periods and we found that the antibiotic resistance rate to cefotaxime was significantly increased from 5.4% to 16.8% (P=0.008) and that to TZP was significantly decreased from 40.5% to 7.9% (P<0.001). CONCLUSION: Over the past 9 years, the resistance rate to cefotaxime has increased but the resistance rate to TZP has decreased. Thus, it is important to continue to investigate the antibiotic resistance rates of bacteria in the community.

Clinical Study of Prevalence of Antibiotic Resistance of Escherichia coli in Urinary Tract Infection in Children: A 9-year Retrospective, Single Center Experience

PURPOSE: The aim of this study was to determine the prevalence of antibiotic susceptibility and resistance of Escherichia coli in urinary tract infections (UTIs) in children. METHODS: We retrospectively reviewed the clinical records of 212 inpatients aged 18 years or younger with UTIs treated at the Pediatric Department of Dongguk University Gyeongju Hospital between January 2008 and December 2016. For comparison, patients were divided into three groups according to age as follows: group 1, ≤1 month; group 2, >1 month to ≤12 months; and group 3, ≥13 months. The antibiotic resistance rates from January 2008 to December 2012 (study period 1) and from January 2013 to December 2016 (study period 2) were analyzed statistically by group. RESULTS: As the patient age increased, the antibiotic resistance rate to ampicillin (P=0.013), levofloxacin (P=0.050), piperacillin/tazobactam (TZP) (P<0.001), and trimethoprim/sulfamethoxazole (P=0.002) increased. The frequency of extended spectrum beta-lactamase producing E. coli showed a significant difference from 5 cases (4.6%) in study period 1 and 16 cases (15.8%) in study period 2 (P=0.007). The antibiotic resistance rate of E. coli was compared between the two time periods and we found that the antibiotic resistance rate to cefotaxime was significantly increased from 5.4% to 16.8% (P=0.008) and that to TZP was significantly decreased from 40.5% to 7.9% (P<0.001). CONCLUSION: Over the past 9 years, the resistance rate to cefotaxime has increased but the resistance rate to TZP has decreased. Thus, it is important to continue to investigate the antibiotic resistance rates of bacteria in the community.