• Pediatric Infection and Vaccine
• /
• v.24 no.2
• /
• pp.87-94
• /
• 2017

Purpose: The inappropriate prescription of antibiotics in children with upper respiratory tract infection (URTI) is common. This study evaluated the factors that influence antibiotics use in hospitalized children with viral URTI confirmed by reverse transcriptase-polymerase chain reaction (RTPCR) assay. Methods: The medical records of admitted patients who performed RT-PCR assay for respiratory virus pathogens from January 2013 to November 2014 were examined. The demographic and clinical features were compared between patients who were administered antibiotics at admission and those who were not. We also investigated differences between children who continued antibiotics and those who stopped antibiotics after a viral pathogen was identified. Results: In the total 393 inpatients, the median age was 23 months (interquartile range, 13 to 41.3 months). Antimicrobial agents were prescribed in 79 patients (20.1%) at admission. Patients with acute otitis media (AOM) had higher rates of antibiotics prescription than those without AOM (48.1% vs. 2.2%, P<0.001), with an adjusted odds ratio of 91.1 (95% confidence interval, 30.5 to 271.7). Level of high-sensitivity C-reactive protein and the proportion of acute rhinosinusitis were also significantly associated with antibiotics use (P<0.001). Among the 44 patients with viruses identified using the RT-PCR method during hospitalization, antibiotic use was continued in 28 patients (63.6%). AOM was statistically associated with continued antibiotic use in the patients (P=0.002). Conclusions: Although the respiratory virus responsible for URTI etiology is identified, clinicians might not discontinue antibiotics if AOM is accompanying. Therefore, careful diagnosis and management of AOM could be a strategy to reduce unjustified antibiotic prescriptions for children with URTI.

• IMMUNE NETWORK
• /
• v.23 no.3
• /
• pp.25.1-25.17
• /
• 2023

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection induces excessive pro-inflammatory cytokine release and cell death, leading to organ damage and mortality. High-mobility group box 1 (HMGB1) is one of the damage-associated molecular patterns that can be secreted by pro-inflammatory stimuli, including viral infections, and its excessive secretion levels are related to a variety of inflammatory diseases. Here, the aim of the study was to show that SARS-CoV-2 infection induced HMGB1 secretion via active and passive release. Active HMGB1 secretion was mediated by post-translational modifications, such as acetylation, phosphorylation, and oxidation in HEK293E/ACE2-C-GFP and Calu-3 cells during SARS-CoV-2 infection. Passive release of HMGB1 has been linked to various types of cell death; however, we demonstrated for the first time that PANoptosis, which integrates other cell death pathways, including pyroptosis, apoptosis, and necroptosis, is related to passive HMGB1 release during SARS-CoV-2 infection. In addition, cytoplasmic translocation and extracellular secretion or release of HMGB1 were confirmed via immunohistochemistry and immunofluorescence in the lung tissues of humans and angiotensin-converting enzyme 2-overexpressing mice infected with SARS-CoV-2.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2021.04a
• /
• pp.3-3
• /
• 2021

The ongoing global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has not only influenced over 1.26 billion people but also caused 2.77 million deaths worldwide (as of March 28, 2021). The vaccination could be the most efficient strategy to prevent SARS-CoV-2 infection. However, the continuous emergence of novel variants such as VUI-202012/01 (United Kingdom) and 501.V2 (South Africa) raises huge concerns about the effectiveness of the vaccine designed to target the original virus strain. Since ancient times regardless of the East and West, the plants which refered in this presentation have been consumed not only as food but also as a natural medicine to treat diverse diseases including infectious diseases. Importantly, these plants contain secondary metabolites that display antiviral activity involved in the inhibition of viral adsorption, penetration, and replication. Also, plant-derived natural medicines are expected to have a wider range of efficacy and fewer side effects than synthetic medicine, discovering novel plant-based viral agents would be a promising strategy to fight against SARS-CoV-2.

• Pediatric Infection and Vaccine
• /
• v.29 no.2
• /
• pp.70-76
• /
• 2022

Coronavirus disease 2019 (COVID-19) in patients with underlying diseases, is associated with high infection and mortality rates, which may result in acute respiratory distress syndrome and death. Mucopolysaccharidosis (MPS) type II is a progressive metabolic disorder that stems from cellular accumulation of the glycosaminoglycans, heparan, and dermatan sulfate. Upper and lower airway obstruction and restrictive pulmonary diseases are common complaints of patients with MPS, and respiratory infections of bacterial or viral origin could result in fatal outcomes. We report a case of COVID-19 in a 16-year-old adolescent with MPS type II, who had been treated with idursulfase since 5 years of age. Prior to infection, the patient's clinical history included developmental delays, abdominal distension, snoring, and facial dysmorphism. His primary complaints at the time of admission included rhinorrhea, cough, and sputum without fever or increased oxygen demand. His heart rate, respiratory rate, and oxygen saturation were within the normal biological reference intervals, and chest radiography revealed no signs of pneumonia. Consequently, supportive therapy and quarantine were recommended. The patient experienced an uneventful course of COVID-19 despite underlying MPS type II, which may be the result of an unfavorable host cell environment and changes in expression patterns of proteins involved in interactions with viral proteins. Moreover, elevated serum heparan sulfate in patients with MPS may compete with cell surface heparan sulfate, which is essential for successful interaction between the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein and the host cell surface, thereby protecting against intracellular penetration by SARS-CoV-2.

• Clinical and Experimental Pediatrics
• /
• v.63 no.7
• /
• pp.239-250
• /
• 2020

The novel coronavirus disease 2019 (COVID-19) is spreading globally. Although its etiologic agent is discovered as severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), there are many unsolved issues in COVID-19 and other infectious diseases. The causes of different clinical phenotypes and incubation periods among individuals, species specificity, and cytokine storm with lymphopenia as well as the mechanism of damage to organ cells are unknown. It has been suggested that in viral pneumonia, virus itself is not a direct cause of acute lung injury; rather, aberrant immune reactions of the host to the insults from viral infection are responsible. According to its epidemiological and clinical characteristics, SARS-CoV-2 may be a virus with low virulence in nature that has adapted to the human species. Current immunological concepts have limited ability to explain such unsolved issues, and a presumed immunopathogenesis of COVID-19 is presented under the protein-homeostasis-system hypothesis. Every disease, including COVID-19, has etiological substances controlled by the host immune system according to size and biochemical properties. Patients with severe pneumonia caused by SARS-CoV-2 show more severe hypercytokinemia with corresponding lymphocytopenia than patients with mild pneumonia; thus, early immunomodulator treatment, including corticosteroids, has been considered. However, current guidelines recommend their use only for patients with advanced pneumonia or acute respiratory distress syndrome. Since the immunopathogenesis of pneumonia may be the same for all patients regardless of age or severity and the critical immune-mediated lung injury may begin in the early stage of the disease, early immunomodulator treatment, including corticosteroids and intravenous immunoglobulin, can help reduce morbidity and possibly mortality rates of older patients with underlying conditions.

• Clinical and Experimental Pediatrics
• /
• v.48 no.3
• /
• pp.266-275
• /
• 2005

Purpose : Acute respiratory tract infections are the most common illnesses in children. The great majority of these infections involving lower respiratory tracts infections(LRTIs) are caused by respiratory viruses such as respiratory syncytial virus(RSV), parainfluenza virus(PIV), influenza virus (Flu), and adenovirus(ADV), etc. Our purpose was to determine seasonal epidemiology and clinical characteristic features of each viral infection. Methods : Nasopharyngeal aspirate(NPA)s were collected from 4,554 hospitalized children diagnosed as LRTIs on the first day of admission. The study period was from September 1998(Autumn) through May 2003(Spring). Respiratory viruses were detected in 881(19 percent) cases by isolation of the virus or by antigen detection method using indirect immunofluorescent staining. We reviewed the medical records of 837 cases retrospectively. Results : The identified pathogens were RSV in 485 cases(55 percent), PIV in 152 cases(17 percent), FluA in 114 cases(13 percent), ADV in 79 cases(9 percent) and FluB in 51 cases(6 percent). Outbreaks of RSV occurred every year, mostly in the November through December period and of PIV in the April through June period. LRTIs by FluA reached the highest level in January, 2002. FluB infection showed an outbreak in April, 2002. The clinical diagnoses of viral LRTIs were bronchiolitis in 395 cases(47 percent), pneumonia in 305 cases(36 percent), croup in 73 cases(9 percent) and tracheobronchitis in 64 cases(8 percent). Conclusion : Viruses are one of the major etiologic agents of acute LRTIs in chidren. Therefore, we must continue to study their seasonal occurrence and clinical features to focus on management, and also for reasons of prevention.

• Tuberculosis and Respiratory Diseases
• /
• v.85 no.4
• /
• pp.320-331
• /
• 2022

Coronavirus disease 2019 (COVID-19) has become a major health burden worldwide, with over 450 million confirmed cases and 6 million deaths. Although the acute phase of COVID-19 management has been established, there is still a long way to go to evaluate the long-term clinical course or manage complications due to the relatively short outbreak of the virus. Pulmonary fibrosis is one of the most common respiratory complications associated with COVID-19. Scarring throughout the lungs after viral or bacterial pulmonary infection have been commonly observed, but the prevalence of post-COVID-19 pulmonary fibrosis is rapidly increasing. However, there is limited information available about post-COVID-19 pulmonary fibrosis, and there is also a lack of consensus on what condition should be defined as post-COVID-19 pulmonary fibrosis. During a relatively short follow-up period of approximately 1 year, lesions considered related to pulmonary fibrosis often showed gradual improvement; therefore, it is questionable at what time point fibrosis should be evaluated. In this review, we investigated the epidemiology, risk factors, pathogenesis, and management of post-COVID-19 pulmonary fibrosis.

• The Journal of Korean Society of Virology
• /
• v.26 no.1
• /
• pp.9-22
• /
• 1996

Respiratory Syncytial virus (RSV) is an important cause of acute lower respiratory tract infections in human, with infants and young children being particularly susceptible. In the temperate zones, sharp annual outbreaks of RSV occur during the colder months, in both the northern and the southern hemisphere. RSV is unusual in that it can repeatedly reinfect individuals throughout life and infect babies in the presence of maternal antibody. RSV isolates can be divided into two subgroups, A and B, on the basis of their reactions with monoclonal antibodies, and the two subgroups are also distinct at the nucleotide sequence level. The specific diagnosis of RSV infection was best made by isolation of virus in tissue culture, identification of viral antigen, or by specific serologic procedures. Recently, rapid detection of RSV and analysis of RSV strain variation became possible by development of methods of reverse transcription and polymerase chain reaction amplification. In this study, to determine the genetic diversity of RSV found in Korea, 173 bp and 164 bp spanning selected regions of the RSV F and SH genes were enzymatically amplified and sequenced, respectively. Eight for F gene and three for SH gene were detected in 66 nasopharyngeal swap samples tested. Two major antigenic subgroups, A and B were confirmed from Korean samples (seven for subgroup A and one for subgroup B). At the nucleotide level of the F gene region, Korean subgroup A strains showed 95-99% homologies compared to the prototype A2 strain of subgroup A and 93-100% homologies among Korean subgroup A themselves. For the SH gene region, Korean subgroup A strain showed 97.5% homology compared to the prototype A2 strain of subgroup A, and Korean subgroup B strain showed 97% homology compared to the prototype 18537 strain of subgroup B. Most of base changes were transition and occured in codon position 3, which resulted in amino acid conservation. Using the maximum parsimony method, phylogenetic analysis indicated that Korean RSV strains formed a group with other RSV strains isolated from the United States, Canada, the Great Britain and Australia.

• Investigative Magnetic Resonance Imaging
• /
• v.19 no.3
• /
• pp.186-190
• /
• 2015

Acute disseminated encephalomyelitis (ADEM) is a demyelinating and inflammatory condition of the central nervous system, occurring predominantly in white matter. ADEM involving the rhombencephalon without affecting the white matter is very rare. Here, we present an unusual case of ADEM involving only the rhombencephalon in a 4-year-old Asian girl. The patient complained of pain in the right lower extremities, general weakness, ataxia, and dysarthria. The initial brain CT showed subtle ill-defined low-density lesions in the pons and medulla. On brain MRI, T2 high signal intensity (T2-HSI) lesions with mild swelling were present in the pons, both middle cerebellar peduncles, and the anterior medulla. The initial diagnosis was viral encephalitis involving the rhombencephalon. Curiously, a cerebrospinal fluid (CSF) study revealed no cellularity, and negative viral marker findings. Three weeks later, follow up brain MRI showed that the extent of the T2-HSI lesions in the brain stem had decreased. After reinvestigation, it was found that she had a prior history of upper respiratory infection. In this case, we report the very rare case of a patient showing isolated involvement of the rhombencephalon in ADEM, mimicking viral rhombencephalitis on CT and MR imaging. ADEM can involve unusual sites such as the rhombencephalon in isolation, without involvement of the white matter or deep gray matter and, therefore, should be considered even when it appears in unusual anatomical areas. Thorough history taking is important for making a correct diagnosis.

• Pediatric Infection and Vaccine
• /
• v.7 no.1
• /
• pp.94-107
• /
• 2000

Purpose : The purpose of this study is to know the clinical manifestations and the severity of adenoviral lower respiratory tract infections(LRTI) in Korean children. Methods : Adenoviral respiratory infection was diagnosed by viral culture in HEp-2 cell and indirect immunofluorescent technique with nasal aspirates. Isolated adenoviruses were typed by neutralization test. Retrospective chart review was done in patients with adenoviruses were typed by neutralization test. Retrospective chart review was done in patients with adenoviral lower respiratory tract infection, who were brought to Seoul National University Children's Hospital from November 1990 through February 1998. Results : Adenovirus was isolated in 87 cases. Of 84 cases serotyped, type 1 was recovered in 3 cases, type 2 in 13 cases, type 3 in 13, type 4 and 5 in 4 cases each other, type 6 in 1 cases, type 7 in 36 cases, type 11 in 1 case and the other types in 9 cases. Adenoviral lower respiratory infection occurred sporadically throughout the year but from November 1995 through February 1998, an outbreak of adenovirus type 7 lower respiratory infection was observed in number upto 36 case. The incidence of adenoviral infection peaked in young children between 6 months and 5 years of age and the mean age was 1 year 11 months old. There were 10 cases of mixed infection with another pathogen. Clinical diagnosis were pneumonia(88%), acute broncholitis(5.4%), acute tracheobronchitis(5.4%), croup(1.3%). The clinical features of adenoviral lower respiratory infection were severe especially in type 3 and 7 infections in aspect of fever duration, ventilator care. Extrapulmonary manifestations were gastrointestinal symptoms in 23 cases(31%), hepatomegaly in 36 cases(53%), seizure and mental alteration in 13 cases(20.3%). In chest radiographic findings, parahilar and peribronchial infiltration were in 49 cases(67%), hyperaeration in 21 cases(29%), atelectasis in 14 cases(19%), consolidation in 39 cases(53%) and bilateral pneumonic infiltration in 28 cases(38%). Among thirty six adenovirus type 7 LRTI, 15 patients(41.6%) had pleural effusion and 3 patients had chest tube insertion. Number of fetal cases related to adenovirus were 9 cases(12%) and fetal cases due to ventilatory failure were 7(11%). Conclusion : During 7 year period of studying adenoviral lower respiratory infection, we identified the serotypes of adenovirus. Among the serotypes, adenovirus type 7 were epidemically isolated. Adenovirus were isolated in severe lower respiratory infection of young children aged between 6 months and 5 years and related to death of the patients, especially when the patients had underlyng diseases or were infected by adenovirus type 7.