• Pediatric Infection and Vaccine
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• v.22 no.2
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• pp.106-112
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• 2015

Purpose: The long-term administration of antibiotics interferes with bacterial culture in the middle ear fluids (MEFs) of young children with otitis media with effusion (OME). The purpose of this study is to determine whether molecular diagnostics can be used for rapid and direct detection of the bacterial pathogen in culture-negative MEFs. Methods: The specificity and sensitivity of both polymerase chain reaction (PCR) and loop-mediated isothermal amplification (LAMP) to the lytA gene of Streptococcus pneumoniae were comparatively tested and then applied for pneumococcal detection in the clinical MEFs. Results: The detection limit of the PCR assay was approximately $10^4$ colony forming units (CFU), whereas that of LAMP was less than 10 CFU for the detection of S. pneumoniae. Both PCR and LAMP did not amplify nucleic acid at over $10^6$ CFU of H. influenzae or M. catarrhalis, both of which were irrelevant bacterial species. Of 22 culture-negative MEFs from children with OME, LAMP positivity was found in twelve MEFs (54.5%, 12/22), only three of which were PCR-positive (25%, 3/12). Our results showed that the ability of LAMP to detect pneumococcal DNA is over four times higher than that of PCR (P<0.01). Conclusions: As a high-resolution tool able to detect nucleic acid levels equivalent to <10 CFU of S. pneumoniae in MEFs without any cross-reaction with other pathogens, lytA -specific LAMP may be applied for diagnosing pneumococcus infection in OME as well as evaluating the impact of a pneumococcal conjugate vaccine against OME.

• Pediatric Infection and Vaccine
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• v.19 no.1
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• pp.19-27
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• 2012

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.

• Clinical and Experimental Pediatrics
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• v.48 no.11
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• pp.1193-1200
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• 2005

Purpose : Invasive bacterial infection is a major cause of morbidity and mortality in children. Previously, we reported etiology of invasive infections in healthy children in 1985-1995. This study was performed to update etiology of invasive bacterial infections in the previously healthy children. Methods : We reviewed medical records of 98 episodes of invasive bacterial infections in immunocompetent children at the Seoul National University Children's Hospital in 1996-2004. Results : The frequent pathogens identified over all age groups were Streptococcus pneumoniae (33%) and Staphylococcus aureus(33%). The proportion of Salmonella species and Haemophilus influenzae has been declined to 4% each from 23% and 14%, respectively, compared to previous study. S. agalactiae was the most common isolate in the infants ${\leq}3$ months. Among the infants and children aged 3 months to 2 years and children of 2-5 years, S. pneumoniae(57%, 52%, respectively, in each group) was the most common isolates followed by S. aureus(17% and 24%, respectively). S. aureus was the most common isolates(73%) in children >5 years. Primary bacteremia was the most common clinical diagnosis(27%). S. pneumoniae was responsible for 42% of primary bacteremia, 50% of meningitis, and 69% of bacteremic pneumonia and empyema. S. aureus accounted for 80% of bone and joint infections. The case fatality rate was 8.1% for all invasive infections. Conclusion : We reviewed frequency of bacterial agents of invasive infections in children. The data may be useful for pediatricians to select adequate empirical antibiotics in the management of invasive bacterial infections.

• Clinical and Experimental Pediatrics
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• v.46 no.4
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• pp.345-350
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• 2003

Purpose : Bacterial meningitis is a serious infection of childhood associated with a significant morbidity and mortality. Repeated cerebrospinal fluid(CSF) examination is a useful prognostic indicator and a delayed sterilization is associated with a higher incidence of neurologic abnormalities. In this study we tried to determine the prognostic value of repeated CSF latex agglutination testing. Methods : We retrospectively evaluated 19 patients admitted to Ewha Womans University Mokdong Hospital for bacterial meningitis from January 1997 to June 2002. Bacterial meningitis was confirmed by a positive CSF culture and a positive CSF latex agglutination test. Repeated CSF examinations were done at three, seven, 14, 21 and 28 days after antibiotics therapy. Neuroradiologic studies were performed. Results : The mean age was $10.6{\pm}12.3months$(range; two to 33 months). The male to female ratio was 2.8 : 1. The causative organisms were Haemophilus influenzae type b 57.9%, Group B Streptococcus 21.1%, Streptococcus pneumoniae 15.7% and Escherichia coli 5.3%. Three days after the initiation of antibiotics therapy, repeated CSF latex agglutination tests persisted as positive in nine (47.4%) out of 19 cases, but all CSF cultures became negative. In those cases with negative latex agglutination tests three days after antibiotics therapy, neuroradiologic findings were completely normal. But, in cases with positive latex agglutination tests three days after antibiotics therapy, neuroradiologic abnormalities such as cerebral infarction, encephalomalasia occurred in 44.4%. Conclusion : Repeated CSF latex agglutination testing was valuable as a prognostic factor in bacterial meningitis. Neuroradiologic abnormalities may occur in cases with delayed clearance of CSF latex agglutination tests more often than in cases with negative latex agglutination tests three days after antibiotics therapy.

• Pediatric Infection and Vaccine
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• v.10 no.2
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• pp.208-214
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• 2003

Purpose : We performed a retrospective study on bacterial meningitis in children, pertaining to the causative organisms, bacterial resistance to antibiotics and the effect of recent introduction of Haemophilus influenzae type b(Hib) vaccine. Methods : We analysed the forty-three cases of bacterial meningitis which had been treated at the Inha University Hospital from June 1996 to June 2003. Results : Nineteen cases(44.2%) of them were infants younger than 2 months of age, and 29 cases(67.5%) younger than 1 year of age. The common causative organisms under 2 months of age were group B streptococcus(GBS)(47.4%), E. coli(21.1%), and Klebsiella pneumoniae(21.1%). In the age group beyond 2 months of age, S. pneumoniae were seen in 50 %, H. influenzae in 16.7% and N. meningitidis in 16.7%. All of the five cases of Hib meningitis had not been vaccinated for Hib. There has been no Hib meningitis cases since 2001. Overall fatality rate was 4.5%, and complication occurred in 39%. Complications was significantly less frequent in patients resumed to be treated within 48 hours after onset compared to after 48 hours after onset. Penicillin resistance of S. pneumoniae and GBS isolated among bacterial meningitis cases was high. Conclusion : Timing of treatment after the onset of the disease appeared the most important factor for prognosis of bacterial meningitis. The cases of H. influenzae meningitis have decreased probably due to Hib vaccination.