• Clinical and Experimental Pediatrics
• /
• v.46 no.10
• /
• pp.1024-1028
• /
• 2003

Influenza-associated encephalopathy is regarded as one of the major neurologic disease entities along with those of Reye syndrome, acute necrotizing encephalopathy, and myelitis which are known to be related to influenza virus, mostly type A. And it is being actively researched in Japan as it has caused a tremendous increase in the number of deaths from 1997 to 2002, but it has not been yet reported in the Korean pediatric medical community. It attacks those previously healthy children, who have not been vaccinated. Patients start with such symptoms as fever and common respiratory problems, but within 24 to 48 hours they suffer from seizures with acute mental deterioration, become worse, and suffer multiple organ failures including marked elevated transaminase levels as well as coagulopathy. It induces deaths in a couple of days after the symptoms appear or remains a serious neurologic sequelae. Confirmative diagnosis is used to demonstrate influenza viral infection. We report here a 37 month aged boy who was admitted to our hospital during the last influenza season under the diagnosis of influenza associated encephalopathy on the basis of serologic testing by hemagglutinin inhibition(HI). This is the first report confirmed by increased antibody titer of the influenza A virus in Korea.

• Clinical and Experimental Pediatrics
• /
• v.45 no.12
• /
• pp.1519-1527
• /
• 2002

Purpose : Although influenza virus is one of the most important causes of acute respiratory tract infections(ARTIs) in children, virus isolation is not popular and there are only a few clinical studies on influenza in Korea. We evaluated the epidemiologic and clinical features of ARTIs by influenza virus in children. Methods : From February 1995 to August 2001, nasopharyngeal aspirations were obtained and cultured for the isolation of influenza virus in children admitted with ARTIs. The medical records of patients with influenza virus infection were reviewed retrospectively. Results : Respiratory viruses were isolated in 997(22.0%) out of 4,533 patients examined, and influenza virus was isolated in 164 cases(3.6%). Influenza virus was isolated year after year mainly from December to April of next year. The ratio of male and female was 1.9 : 1 with a median age of 15 months. The most common clinical diagnosis of influenza virus infection was pneumonia, and fever and cough developed in most patients. There was no difference between influenza A and B infection in clinical diagnoses and symptoms. All patients recovered without receiving antiviral treatment except for one patient diagnosed with pneumonia who had underlying disease of Down syndrome with ventricular septal defect. Conclusion : ARTIs caused by influenza virus developed every winter and spring during the period of study. Because fatal complication can develop in the high risk group, prevention, early diagnosis and proper management of influenza should be emphasized.

• Clinical and Experimental Pediatrics
• /
• v.56 no.4
• /
• pp.165-175
• /
• 2013

Purpose: There was a global increase in the prevalence of oseltamivir-resistant influenza viruses during the 2007-2008 influenza season. This study was conducted to investigate the occurrence and characteristics of oseltamivir-resistant influenza viruses during the 2007-2008 and 2008-2009 influenza seasons among patients who were treated with oseltamivir (group A) and those that did not receive oseltamivir (group B). Methods: A prospective study was conducted on 321 pediatric patients who were hospitalized because of influenza during the 2007-2008 and 2008-2009 influenza seasons. Drug resistance tests were conducted on influenza viruses isolated from 91 patients. Results: There was no significant difference between the clinical characteristics of groups A and B during both seasons. Influenza A/H1N1, isolated from both groups A and B during the 2007-2008 and 2008-2009 periods, was not resistant to zanamivir. However, phenotypic analysis of the virus revealed a high oseltamivir $IC_{50}$ range and that H275Y substitution of the neuraminidase (NA) gene and partial variation of the hemagglutinin (HA) gene did not affect its antigenicity to the HA vaccine even though group A had a shorter hospitalization duration and fewer lower respiratory tract complications than group B. In addition, there was no significant difference in the clinical manifestations between oseltamivir-susceptible and oseltamivir-resistant strains of influenza A/H1N1. Conclusion: Establishment of guidelines to efficiently treat influenza with oseltamivir, a commonly used drug for treating influenza in Korean pediatric patients, and a treatment strategy with a new therapeutic agent is required.

• Pediatric Infection and Vaccine
• /
• v.14 no.1
• /
• pp.69-74
• /
• 2007

Purpose : Human coronanviruses (hCovs) including hCoV-229E and hCoV-OC43 have been known as etiologic agents of the common colds and were regarded as clinically insignificant agents. However, recent identification of hCoV-NL63 and hCoV-HKU1 in children with lower respiratory tract infections has evoked the clinical concerns about their prevalence and the clinical significance of these hCoVs in children. This study was performed to investigate the prevalence of hCoVs in children with community-acquired pneumonia. Methods : From March 2006 to January 2007, nasopharyngeal specimens collected from children hospitalized with pneumonia, were tested for the presence of common respiratory viruses (respiratory syncytial virus, influenza A, influenza B, parainfluenza viruses, and adenovirus) using multiplex reverse transcriptase polymerase chain reaction (RT-PCR). Human metapneumovirus (hMPV) infection was excluded by nested RT-PCR using primers for the F-gene. To detect the different strains of hCoVs, nested RT-PCR assays specific for hCoVNL63, hCoV-OC43, hCoV-229E, and hCoV-HKU1 were performed. Results : Out of the 217 nasopharyngeal aspirate from children aged under 15 years, respiratory syncytial virus (RSV) was detected in 32 patients, hMPV in 18, human parainfluenza virus in 10, influenza virus A in 2, and adenovirus in 6. HCoVs were detected by RT-PCR in 8 (3.7%) of the 217 patients, hCoV-229E in 1, hCoV-NL63 in 3, and hCoVOC43 in 4 patients. HCoV-HKU1 was not detected in this study population. Conclusion : Recently identified hCoV-NL63 and hCoV-HKU1 seemed to have a little clinical significance in Korean children with severe or hospitalized community-acquired pneumonia.

• Pediatric Infection and Vaccine
• /
• v.14 no.1
• /
• pp.47-54
• /
• 2007

Purpose : Viral respiratory tract infection is most common cause for admission to hospital in children. There are many cases with elevated transaminase level in patients with viral lower respiratory tract infection (LRTI). The aim of this study was to compare indexes of disease severity such as duration of assisted ventilation, length of hospital stay and Respiratory Distress Assessment Instrument (RDAI) score in children with viral LRTI with and without elevated transaminase levels and to determine the etiology related to elevated transaminase levels in this patients group. Methods : Virological analysis was done from respiratory specimens obtained from patients with LRTI admitted to Kangnam Sacred Heart Hospital from Jan. 2003 to Jun. 2005. Viral diagnosis was made by isolation of viruses employing HEp-2 cell culture from nasopharyngeal aspiration. Medical records of children were reviewed retrospectively. We compared age, sex, RDAI score, Respiratory Rate (RR) score and mean duration of hospital stay between patients with elevated transaminase levels (Patient Group) and patients with normal transaminase levels (Control Group). Results : Viruses were isolated from 181 children with LRTI. 16 cases were excluded according to criteria. 28 cases (17.0%) had elevated transaminase levels (Patient group) and 137 cases (83.0%) had normal transaminase levels (Control group). There were no significant difference in duration of fever, RR score, RDAI score, incidence of $O_2$ inhalation and duration of hospital stay between patient group and control group. We found 17 (60.7%) cases of RSV, 4 cases (14.3%) of parainfluenza, 4 cases (14.3%) of influenza B virus, 3 cases (10.7%) of adenovirus and 1 case (3.6%) of influenza A virus infection in patient group and 78 cases (56.9%) of RSV, 28 cases (20.4%) of parainfluenza virus, 13 cases (9.5%) of influenza A virus, 9 cases (6.6%) of influenza B virus, 6 cases (4.4%) of adenovirus and 3 cases (2.2%) of coxsackie virus infection in control group. Conclusion : There were 28 cases (17.0%) with elevated transaminase level among patients with virus isolated LRTI. There was no relation between elevated transaminase level and severity of disease. The viral etiologies in two groups were not significantly different. There was no significant difference of age distribution between two groups.

• Clinical and Experimental Pediatrics
• /
• v.52 no.7
• /
• pp.785-790
• /
• 2009

Purpose : Febrile convulsions are a common pediatric neurological disease, and it is important to prevent such a disease by controlling the risk factors that may recur. A recent report states that influenza virus infections have a high probability of a relationship with febrile convulsions; therefore, it is necessary to identify the clinical properties of febrile convulsions in relation to domestic influenza virus infections. Methods : Between November 2005 and February 2008, children hospitalized because of febrile convulsions and subsequently confirmed to have influenza infections were enrolled as subjects (patient group, n=11). The control subjects were those admitted with influenza virus infections but no febrile convulsions (control group 1, n=46) and those who developed febrile convulsions without influenza virus infection (control group 2, n=53). Results : The patient group showed a higher maximum body temperature ($39.3{\pm}0.5^{\circ}C$), more histories of past febrile convulsions (72.7%), and a shorter total duration of fever ($2.9{\pm}1.2$ days) than control group 1. When multivariate analysis was performed, the probability of febrile convulsions was found to be as high as 225.9 times in patients who had influenza virus infections with a past history of febrile convulsions (OR=225.9, 95% CI: 1.7-4780.0, P<0.05). When patients with febrile convulsions were compared based on the symptoms of influenza virus infections, the patient group showed a shorter duration of fever ($0.9{\pm}0.7$ days) before convulsion than control group 2; these convulsions were mostly a recurrence of febrile convulsions. When multivariate analysis was performed, the cases with a past history of febrile convulsions showed 5.5 times (OR=5.5, 95% CI: 1.2-25.1, P=0.03) the probability of convulsions when infected with the influenza virus, and this probability decreased by 0.3 times over one-day increments of the febrile period until febrile convulsions (95% CI: 0.1-0.9, P=0.02). Maximum body temperature, total duration of fever, family history of febrile convulsions, and complex febrile convulsions did not show a statistical significance. Conclusion : In cases of pediatric influenza virus infection, the past history of febrile convulsions could be identified within the risk factor of recurrent febrile convulsions. Therefore, influenza vaccination of children having a past history of febrile convulsions will be helpful to avoid the recurrence of these convulsions.

• The Korean Journal of Health Service Management
• /
• v.10 no.4
• /
• pp.213-223
• /
• 2016

Objectives : This study was conducted to examine the educational status and needs of both parents and kindergarten teachers pertaining to the prevention of infectious diseaes in children. Methods : The participants were 280 parents and 147 kindergarten teachers. Data were collected from August 21, 2013 to December 30, 2014. Results : Only 16.7% of parents had educational experience with infectious diseases. The source of their education was broadcast media and their preferred educational method was the internet. Parents reported that the childhood infection about which they should be educated were influenza (30.4%) followed by hand-foot-and-mouth disease (13.9%), food poisoning (6.4%), and so on. About 27.2% of kindergarten teachers had received an education about infectious diseases, and the major source of their education was refresher training. The teachers' preferred educational method was the internet. The teachers wanted to be educated about influenza (22.4%), hand-foot-and-mouth disease (20.4%), food poisoning (20.4%) and so on. Conclusions : Educational programs should be developed and applied to children, parents and kindergarten teachers based on consideration of their educational needs.

• Clinical and Experimental Pediatrics
• /
• v.57 no.1
• /
• pp.29-34
• /
• 2014

Purpose: In this study, we aimed to investigate the prevalence of year-round respiratory viral infection in children with lower respiratory tract infection (LRTI) and the relationship between respiratory viral infection and allergen sensitization in exacerbating asthma. Methods: We investigated the sources for acute LRTIs in children admitted to our hospital from May 2010 to April 2011. The 6 most common respiratory viruses were isolated from nasopharyngeal aspirate using multiplex reverse transcription-polymerase chain reaction in 309 children; respiratory syncytial virus (RSV), adenovirus (AV), parainfluenza virus (PIV), influenza virus (IFV), human metapneumovirus (hMPV), rhinovirus (RV). Atopic sensitization was defined if more than 1 serum specific Immunoglobulin E level measured using UniCAP (Pharmacia) was over 0.35 IU/mL. Results: RSV was the most common pathogen of bronchiolitis in hospitalized children through the year. RV or IFV infection was more prevalent in asthma exacerbations compared to other LRTIs. AV and hMPV were more likely to cause pneumonia. RV and IFV were associated with asthma exacerbations in children with atopic sensitization, but not in nonatopic children. Conclusion: RV and IFV are associated with hospitalization for asthma exacerbation in children with atopic sensitization.

• Clinical and Experimental Pediatrics
• /
• v.54 no.10
• /
• pp.405-408
• /
• 2011

Purpose: In autumn 2009, the swine-origin influenza A (H1N1) virus spread throughout South Korea. The aims of this study were to determine the clinical characteristics of children infected by the 2009 H1N1 influenza A virus, and to compare the rapid antigen and realtime polymerase chain reaction (PCR) tests. Methods: We conducted a retrospective review of patients ${\geq}18$ years of age who presented to Soonchunhyang University Hospital in Seoul with respiratory symptoms, including fever, between September 2009 and January 2010. A real-time PCR test was used to definitively diagnose 2009 H1N1 influenza A infection. Medical records of confirmed cases were reviewed for sex, age, and the time of infection. The decision to perform rapid antigen testing was not influenced by clinical conditions, but by individual factors such as economic conditions. Its sensitivity and specificity were evaluated compared to real-time PCR test results. Results: In total, 934 patients tested positive for H1N1 by real-time PCR. The highest number of patients (48.9%) was diagnosed in November. Most patients (48.2%) were aged between 6 and 10 years. Compared with the H1N1 real-time PCR test results, the rapid antigen test showed 22% sensitivity and 83% specificity. Seventy-eight patients were hospitalized for H1N1 influenza A virus infection, and fever was the most common symptom (97.4%). Conclusion: For diagnosis of 2009 H1N1 influenza A virus infection, the rapid antigen test was inferior to the real-time PCR test in both sensitivity and specificity. This outcome suggests that the rapid antigen test is inappropriate for screening.

• Pediatric Infection and Vaccine
• /
• v.21 no.1
• /
• pp.1-8
• /
• 2014

Purpose: The aim for this study was to investigate clinical manifestation of seasonal influenza A and B during the 2012 winter season in Wonju, South Korea. Their clinical and laboratorial characteristics and effect of oseltamivir were compared and analyzed. Methods: Children under the age of 18 years who visited the Wonju Severance Christian Hospital with fever or acute respiratory symptoms and who were diagnosed with influenza A or B by rapid antigen test from nasopharyngeal swab were selected for the study. The medical records of patients were retrospectively reviewed. Results: Influenza A was detected in 374 patients (83.7%), and influenza B in 72 (16.6%). The incidence of influenza A was highest in February (n=186), while that of influenza B was highest in March (n=36). The most common symptoms were fever (n=434, 97.1%) and cough (n=362, 81.0%). No significant differences were observed between influenza A and B in symptoms and laboratory data. Patients who had used oseltamivir within 2 days showed statistically lower admission rate, shorter admission duration, and lower incidence of pneumonia. Conclusion: This study found no statistical difference between influenza A and B, in symptoms, progression, and laboratory test, but those who were treated with oseltamivir given within 2 days of the onset of fever experienced more positive outcomes.