PURPOSE: The aim of this study was to determine the frequency, epidemiology and the clinical manifestation of human metapneumovirus (hMPV) infection in Korean children. METHODS: From February 2010 to January 2012, we collected nasopharyngeal aspiration from 1,554 children who were hospitalized for acute lower respiratory tract infections at the Department of Pediatrics, Severance Children's Hospital. hMPV was detected by performing reverse transcriptase-polymerase chain reaction (RT-PCR). The medical records of the patients with positive results were retrospectively reviewed. RESULTS: We detected hMPV in 99 of the 1,554 hospitalized children. The mean age of the hMPV infected children was 25 months, and 87% of the illnesses occurred between April and June. The most common diagnoses were pneumonia (73%) and bronchiolitis (16%). The clinical manifestations included cough, fever, respiratory distress, hoarseness, tachypnea, and wheezing. Coinfection with other respiratory viruses was found in 43 children (43%). CONCLUSION: hMPV is one of the major virus causing acute respiratory tract infection in the age between 13 months and 48 months old with peaks during April to June. Reports of hMPV in Korea has been increasing but additional studies are required to define the epidemiology and the extent of disease caused by hMPV to determine future development of this illness in Korean children.
Bronchiolitis ; Child ; Child, Hospitalized ; Coinfection ; Cough ; Fever ; Hoarseness ; Humans ; Korea ; Medical Records ; Metapneumovirus ; Pediatrics ; Pneumonia ; Respiratory Sounds ; Respiratory Tract Infections ; Retrospective Studies ; Tachypnea ; Viruses

PURPOSE: Human bocavirus (hBoV), a recently discovered virus, has been detected in children with respiratory tract infections worldwide. The aim of this study was to analyze the frequency and molecular phylogeny of hBoV in the respiratory samples of children with acute respiratory tract infections in 2010. METHODS: Nasopharyngeal samples were collected from 953 children with lower respiratory tract infections at Severance children's hospital in Korea from January 2010 to December 2010. We applied the multiplex PCR technique for the identification of 12 respiratory viruses from the samples. Among the total specimens, hBoV positive samples were subjected to phylogenetic analysis by sequencing a fragment of the VP1/VP2 gene junction. RESULTS: hBoV was detected in 141 (14.8%) among 953 patients. The 61.7% of hBoV-positive samples were found to co-exist with other respiratory viruses. The results of phylogenetic analysis showed that all 141 hBoV-positive isolates were identified as hBoV 1, revealing a high similarity among the isolates (>98%). CONCLUSION: hBoV 1 with minimal sequence variations circulated in children with acute respiratory infections during 2010. More research is needed to determine the clinical severity and outcomes of the minimal sequence variations.
Child ; Child, Hospitalized ; Human bocavirus ; Humans ; Korea ; Multiplex Polymerase Chain Reaction ; Phylogeny ; Respiratory System ; Respiratory Tract Infections ; Viruses

PURPOSE: As the number of children who attend child care centers has increased, concerns has increased about the effect of child day care on childhood illness. This study was conducted to examine the relationship between experience in child care and common infectious diseases in children under 5 years of age. METHODS: Data were collected by surveying 1,000 respondents with children under age 5 through online interviews using a structured questionnaire. The contents of the survey were composed of demographic characteristics, child care facilities usage, experience in infectious diseases, and immunization status. RESULTS: Among the 1,000 children <5 years of age, 78.5% attended a child care facility. Rates of common communicable illnesses were higher in children in child care than for children reared exclusively at home. The predominant communicable diseases which the respondents' children experienced, in order of decreasing frequency, were gastroenteritis (47.1%), otitis media (41.8%) and pneumonia (19.1%). The immunization rate of vaccines that are not included the national immunization program (NIP) (Haemophilus influenzae type b vaccine - 76.6%, hepatitis A vaccine - 63.3%, pneumococcal vaccine - 59.4%, rotavirus vaccine - 43.1%) was lower than that of the NIP vaccines (90.4%). CONCLUSION: Children in child care experience more bouts of common infectious disease, so nationwide policies to prevent or to control the spread of infectious agents in a child-care should be available and appropriate immunization should be emphasized as the most effective method for the control of infectious disease for children.
Child ; Child Care ; Communicable Diseases ; Surveys and Questionnaires ; Day Care, Medical ; Gastroenteritis ; Hepatitis A Vaccines ; Humans ; Immunization ; Immunization Programs ; Influenza, Human ; Otitis Media ; Pneumonia ; Rotavirus ; Vaccination ; Vaccines

During the growing season of 2015, leaf specimens with yellow rust spots were collected from Salix koreensis Andersson, known as Korean willow, in riverine areas in Cheonan, Korea. The fungus on S. koreensis was identified as the rust species, Melampsora yezoensis, based on the morphology of urediniospores observed by light and scanning electron microscopy, and the molecular properties of the internal transcribed spacer rDNA region. Pathogenicity tests confirmed that the urediniospores are the causal agent of the rust symptoms on the leaves and young stems of S. koreensis. Here, we report a new rust disease of S. koreensis caused by the rust fungus, M. yezoensis, a previously unrecorded rust pathogen in Korea.
Chungcheongnam-do ; DNA, Ribosomal ; Fungi ; Korea* ; Microscopy, Electron, Scanning ; Salix* ; Seasons ; Virulence

PURPOSE: Methods for quick and reliable detection of Streptococcus pneumoniae are needed for the diagnosis of pneumococcal disease and vaccine studies. This study aimed to show that sequential multiplex polymerase chain reaction (PCR) is more efficient than conventional culture in achieving S. pneumoniae-positive results. METHODS: Nasopharyngeal (NP) secretions were obtained from 842 pediatric patients admitted with lower respiratory infections at Severance Children's Hospital in Korea between March 2009 and June 2010. For identification and serotype determination of pneumococci from the NP secretions, the secretions were evaluated via multiplex PCR technique with 35 serotype-specific primers arranged in 8 multiplex PCR sets and conventional bacteriological culture technique. RESULTS: Among the results for 793 samples that underwent both bacterial culture and PCR analysis for pneumococcal detection, 153 (19.3%) results obtained by PCR and 81 (10.2%) results obtained by conventional culture technique were positive for S. pneumoniae. The predominant serotypes observed, in order of decreasing frequency, were 19A (23%), 6A/B (16%), 19F (11%), 15B/C (5%), 15A (5%), and 11A (4%); further, 26% of the isolates were non-typeable. CONCLUSION: As opposed to conventional bacteriological tests, PCR analysis can accurately and rapidly identify pneumococcal serotypes.
Culture Techniques ; Humans ; Korea ; Multiplex Polymerase Chain Reaction ; Pneumonia ; Polymerase Chain Reaction ; Respiratory Tract Infections ; Serotyping ; Streptococcus ; Streptococcus pneumoniae

OBJECTIVE: To determine whether the use of contrast enhancement (especially its extent) predicts malignant brain edema after intra-arterial thrombectomy (IAT) in patients with acute ischemic stroke. METHODS: We reviewed the records of patients with acute ischemic stroke who underwent IAT for occlusion of the internal carotid artery or the middle cerebral artery between January 2012 and March 2015. To estimate the extent of contrast enhancement (CE), we used the contrast enhancement area ratio (CEAR)-i.e., the ratio of the CE to the area of the hemisphere, as noted on immediate non-enhanced brain computed tomography (NECT) post-IAT. Patients were categorized into two groups based on the CEAR values being either greater than or less than 0.2. RESULTS: A total of 39 patients were included. Contrast enhancement was found in 26 patients (66.7%). In this subgroup, the CEAR was greater than 0.2 in 7 patients (18%) and less than 0.2 in the other 19 patients (48.7%). On univariate analysis, both CEAR > or =0.2 and the presence of subarachnoid hemorrhage were significantly associated with progression to malignant brain edema (p<0.001 and p=0.004), but on multivariate analysis, only CEAR > or =0.2 showed a statistically significant association (p=0.019). In the group with CEAR > or =0.2, the time to malignant brain edema was shorter (p=0.039) than in the group with CEAR <0.2. Clinical functional outcomes, based on the modified Rankin scale, were also significantly worse in patients with CEAR > or =0.2 (p=0.003) CONCLUSION: The extent of contrast enhancement as noted on NECT scans obtained immediately after IAT could be predictive of malignant brain edema and a poor clinical outcome.
Brain Edema* ; Brain* ; Carotid Artery, Internal ; Humans ; Infarction* ; Middle Cerebral Artery ; Multivariate Analysis ; Stroke ; Subarachnoid Hemorrhage ; Thrombectomy*

PURPOSE: We investigated the clinical difference between single infection and coinfection with respiratory virus in hospitalized children with acute respiratory tract infections. METHODS: We reviewed 727 patients who were admitted with the diagnosis of acute respiratory infection at the Department of Pediatrics, Bundang Jesaeng Hospital between January and December of 2014. Diagnoses were made using the multiplex reverse transcriptase polymerase chain reaction (RT-PCR) assay targeting 16 viruses in nasopharyngeal swabs. Subjects were classified as the single virus infection and coinfection groups. RESULTS: A total of 439 patients were enrolled; 359 (77.2%) under 24 months. Single virus was detected in 279 (63.6%). Coinfection with multiple virus was detected in 160 (36.4%): 126 (28.7%) with 2 viruses, 30 (6.8%), and 4 (0.9%) with 3 to 4 viruses. Viral coinfection was detected in 28 samples (17.5%), with respiratory syncytial virus (RSV) A and rhinovirus being the most dominating combination. There were no clinical differences between the single infection and coinfection groups, except sputum and the frequency of high RSV load. Sputum was significantly more frequent in the coinfection group (P=0.043), and the frequency of high RSV load was significantly higher in the single infection group (P=0.029). Disease severity (high fever, the duration of fever [≥5 days], and the length of hospital stay [≥5 days], O₂ therapy) did not differ significantly between both groups. RSV was a frequent virus of single infection during winter. Coinfection was most common in winter. CONCLUSION: There were no clinical differences between single infection and coinfection, except sputum and the frequency of high RSV load.
Child ; Child, Hospitalized ; Coinfection* ; Diagnosis ; Fever ; Humans ; Length of Stay ; Multiplex Polymerase Chain Reaction ; Pediatrics ; Respiratory Syncytial Viruses ; Respiratory Tract Infections ; Reverse Transcriptase Polymerase Chain Reaction ; Rhinovirus ; Sputum

Juvenile idiopathic arthritis (JIA) can develop extra-articular manifestations, including growth retardation, osteopenia and chronic uveitis. However, pleuropulmonary involvement is rare. Approximately 40% of patients with JIA have abnormal pulmonary function tests without pulmonary symptoms, with the commonest abnormality in carbon monoxide diffusing capacity, but clinically evident pulmonary parenchymal disease in JIA is extremely uncommon. We describe a 15-year-old male with JIA who presented with dyspnea due to interstitial lung disease.
Adolescent ; Arthritis ; Arthritis, Juvenile Rheumatoid* ; Bone Diseases, Metabolic ; Carbon Monoxide ; Dyspnea ; Humans ; Lung Diseases ; Lung Diseases, Interstitial ; Lung* ; Male ; Respiratory Function Tests ; Uveitis