Enterococcal Bacteremia in Children:A Review of Fifty Episodes in a Pediatric Hospital / 감염과화학요법

BACKGROUND: Episode of Enterococcal bacteremia has increasingly been reported for the past 15 years in USA, but there have been few systematic studies on its occurrence among Korean children. This study was carried out to determine the epidemiologic, clinical and laboratory characteristics of enterococcal bacteremia in Korean children. METHODS: Fifty episodes of enterococcal bacteremia among Korean children were retrospectively analyzed. Clinical and microbiological data were collected for all episodes of enterococcal bacteremia which occurried during 9-year period between November, 1992, and August, 2001 at the Seoul National University Children's Hospital. RESULTS: Significant underlying diseases were present in 47 (94%) episodes, including cardiac or abdominal surgery (44%), cardiac disease (30%), and chronic gastrointestinal disorders (16%). Thirty- eight (76%) episodes were nosocomial in origin, and 14 (28%) episodes were polymicrobial bacteremia. The source of bacteremia was identified in 16 (32%) episodes, intravascular device being the most common identifiable source. Of the 47 isolates identified at species level, 20 strains were Enterococcus faecium, 26 Enterococcus faecalis and one Enterococcus avium. Seventy-two percent of E. faecium cases were resistant to ampicillin. 36 cases (80%) had high-level resistance to gentamicin and sixteen cases (36%) to streptomycin. There was no strain resistant to vancomycin. Three clinical patterns were identified; self-limited bacteremia, 20%; low grade sepsis with favorable outcome after specific therapy, 42%; severe and prolonged infection, 30%; and unclassified, 8%. The overall mortality rate was 10.8%. CONCLUSION: Enterococcal bacteremia in children was usually nosocomial and comprised a heterogeneous group. The majority of cases occurred in children with serious underlying diseases. The frequency of high-level resistance to gentamicin in enterococcal isolates was high.

Enterococcal Bacteremia in Children:A Review of Fifty Episodes in a Pediatric Hospital / 감염과화학요법

BACKGROUND: Episode of Enterococcal bacteremia has increasingly been reported for the past 15 years in USA, but there have been few systematic studies on its occurrence among Korean children. This study was carried out to determine the epidemiologic, clinical and laboratory characteristics of enterococcal bacteremia in Korean children. METHODS: Fifty episodes of enterococcal bacteremia among Korean children were retrospectively analyzed. Clinical and microbiological data were collected for all episodes of enterococcal bacteremia which occurried during 9-year period between November, 1992, and August, 2001 at the Seoul National University Children's Hospital. RESULTS: Significant underlying diseases were present in 47 (94%) episodes, including cardiac or abdominal surgery (44%), cardiac disease (30%), and chronic gastrointestinal disorders (16%). Thirty- eight (76%) episodes were nosocomial in origin, and 14 (28%) episodes were polymicrobial bacteremia. The source of bacteremia was identified in 16 (32%) episodes, intravascular device being the most common identifiable source. Of the 47 isolates identified at species level, 20 strains were Enterococcus faecium, 26 Enterococcus faecalis and one Enterococcus avium. Seventy-two percent of E. faecium cases were resistant to ampicillin. 36 cases (80%) had high-level resistance to gentamicin and sixteen cases (36%) to streptomycin. There was no strain resistant to vancomycin. Three clinical patterns were identified; self-limited bacteremia, 20%; low grade sepsis with favorable outcome after specific therapy, 42%; severe and prolonged infection, 30%; and unclassified, 8%. The overall mortality rate was 10.8%. CONCLUSION: Enterococcal bacteremia in children was usually nosocomial and comprised a heterogeneous group. The majority of cases occurred in children with serious underlying diseases. The frequency of high-level resistance to gentamicin in enterococcal isolates was high.

Pharyngeal Colonization Rate of Penicillin-resistant Streptococcus pneumoniae among Day-care Center Children in Seoul, Korea / 감염

BACKGROUND: Antimicrobial resistance of Streptococcus pneumoniae presents a challenge to the clinicians in developing countries, particularly against the acute respiratory tract infections, including pneumonia. The present study was to evaluate the carriage rate and the antimicrobial resistance of S. pneumoniae isolated from children at a day-care center. METHODS: Oropharyngeal swabs were done every month for one year in 64 children at a day-care center in Seoul, Korea. Minimum inhibitory concentrations (MICs) of 9 antimicrobial agents (penicillin, ceftriaxone, cefuroxime, erythromycin, chloramphenicol, tetracycline, vancomycin, ciprofloxacin, cefpirome) were determined by agar-dilution method. RESULTS: The ages of the children ranged from 13 to 60 months (mean: 31 months). The overall carriage- rate of pneumococci was 26%, which was highest in December (46%) and lowest in July (3%). A total number of 105 strains of S. pneumoniae were isolated from 404 throat swabs and 68 strains among these were available for MIC tests. Only 8 (12%) strains were susceptible to penicillin, while 50 (73%) were intermediate and 10 (15%) were resistant. The isolates also exhibited high rates of resistance to other beta- lactams (53% and 21% were resistant to cefuroxime and ceftriaxone, respectively). The resistance rates to the other antimicrobial agents were also remarkable; 90% and 88% were resistant to erythromycin and tetracycline, respectively. However, 75% of isolates were susceptible to chloramphenicol and 100% were susceptible to vancomycin. CONCLUSION: There was a high rate of pharyngeal carriage of penicillin-resistant S. pneumoniae among children attending day-care center. Surveillance of pharyngeal cultures may provide useful information the treatment guideline of pneumococcal infections.

Clinical Features of Infections Caused by Streptococcus pyogenes in Children and their Antimicrobial Susceptibility / 감염

BACKGROUND: Streptococcus pyogenes causes most often pharyngitis or tonsillitis but may also be responsible for severe diseases including bacteremia and pneumonia. Recent publications from several geographic areas showed high rates of resistance to erythromycin and newer macrolides, often used in patients allergic to penicillin, in clinical isolates of S. pyogenes. METHODS: Minimum inhibitory concentration of 31 strains of S. pyogenes, isolated at the Seoul National University Children's Hospital from October 1991 through April 1998, were determined for penicillin, ceftriaxone, vancomycin, clindamycin, erythromycin, roxythromycin, and clarithromycin by agar dilution method or E-test. In addition, clinical features of the patients from whom the organisms were isolated were reviewed retrospectively. RESULTS: Of the 28 patients whose medical records were reviewed, the most common clinical presentations were soft-tissue infection (8 cases) and pharyngitis (5 cases). Other presentations included bacteremia without focus, pneumonia, vaginitis, lymphadenitis, omphalitis (two of each); primary peritonitis, rheumatic fever with carditis, scarlet fever, acute otitis media, and disseminated disease (one of each). All of the isolates were susceptible to penicillin, ceftriaxone, and vancomycin. However, 5 isolates (16%) were resistant to erythromycin, and all of the erythromycin-resistant strains were resistant to roxythromycin and clarithromycin as well. Three of these erythromycin-resistant strains were also resistant to clindamycin. CONCLUSION: S. pyogenes may cause serious infections in children. Emergence of resistance in clinical isolates of S. pyogenes to macrolides and clindamycin should be considered in empirical antimicrobial therapy of suspected group A streptococcal infections and in establishment of antibiotic policy in Korea.